diff options
Diffstat (limited to 'Documentation')
40 files changed, 1283 insertions, 650 deletions
diff --git a/Documentation/Changes b/Documentation/Changes index cb2b141b1c3..b95082be4d5 100644 --- a/Documentation/Changes +++ b/Documentation/Changes @@ -33,10 +33,12 @@ o Gnu make 3.79.1 # make --version o binutils 2.12 # ld -v o util-linux 2.10o # fdformat --version o module-init-tools 0.9.10 # depmod -V -o e2fsprogs 1.29 # tune2fs +o e2fsprogs 1.41.4 # e2fsck -V o jfsutils 1.1.3 # fsck.jfs -V o reiserfsprogs 3.6.3 # reiserfsck -V 2>&1|grep reiserfsprogs o xfsprogs 2.6.0 # xfs_db -V +o squashfs-tools 4.0 # mksquashfs -version +o btrfs-progs 0.18 # btrfsck o pcmciautils 004 # pccardctl -V o quota-tools 3.09 # quota -V o PPP 2.4.0 # pppd --version diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 1875e502f87..72968cd5eaf 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -483,17 +483,25 @@ values. To do the latter, you can stick the following in your .emacs file: (* (max steps 1) c-basic-offset))) +(add-hook 'c-mode-common-hook + (lambda () + ;; Add kernel style + (c-add-style + "linux-tabs-only" + '("linux" (c-offsets-alist + (arglist-cont-nonempty + c-lineup-gcc-asm-reg + c-lineup-arglist-tabs-only)))))) + (add-hook 'c-mode-hook (lambda () (let ((filename (buffer-file-name))) ;; Enable kernel mode for the appropriate files (when (and filename - (string-match "~/src/linux-trees" filename)) + (string-match (expand-file-name "~/src/linux-trees") + filename)) (setq indent-tabs-mode t) - (c-set-style "linux") - (c-set-offset 'arglist-cont-nonempty - '(c-lineup-gcc-asm-reg - c-lineup-arglist-tabs-only)))))) + (c-set-style "linux-tabs-only"))))) This will make emacs go better with the kernel coding style for C files below ~/src/linux-trees. diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index b462bb14954..2a3fcc55e98 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -5,7 +5,7 @@ This document describes the DMA API. For a more gentle introduction phrased in terms of the pci_ equivalents (and actual examples) see -DMA-mapping.txt +Documentation/PCI/PCI-DMA-mapping.txt. This API is split into two pieces. Part I describes the API and the corresponding pci_ API. Part II describes the extensions to the API @@ -170,16 +170,15 @@ Returns: 0 if successful and a negative error if not. u64 dma_get_required_mask(struct device *dev) -After setting the mask with dma_set_mask(), this API returns the -actual mask (within that already set) that the platform actually -requires to operate efficiently. Usually this means the returned mask +This API returns the mask that the platform requires to +operate efficiently. Usually this means the returned mask is the minimum required to cover all of memory. Examining the required mask gives drivers with variable descriptor sizes the opportunity to use smaller descriptors as necessary. Requesting the required mask does not alter the current mask. If you -wish to take advantage of it, you should issue another dma_set_mask() -call to lower the mask again. +wish to take advantage of it, you should issue a dma_set_mask() +call to set the mask to the value returned. Part Id - Streaming DMA mappings diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl index b787e4721c9..52e1b79ce0e 100644 --- a/Documentation/DocBook/uio-howto.tmpl +++ b/Documentation/DocBook/uio-howto.tmpl @@ -42,6 +42,12 @@ GPL version 2. <revhistory> <revision> + <revnumber>0.7</revnumber> + <date>2008-12-23</date> + <authorinitials>hjk</authorinitials> + <revremark>Added generic platform drivers and offset attribute.</revremark> + </revision> + <revision> <revnumber>0.6</revnumber> <date>2008-12-05</date> <authorinitials>hjk</authorinitials> @@ -312,6 +318,16 @@ interested in translating it, please email me pointed to by addr. </para> </listitem> +<listitem> + <para> + <filename>offset</filename>: The offset, in bytes, that has to be + added to the pointer returned by <function>mmap()</function> to get + to the actual device memory. This is important if the device's memory + is not page aligned. Remember that pointers returned by + <function>mmap()</function> are always page aligned, so it is good + style to always add this offset. + </para> +</listitem> </itemizedlist> <para> @@ -594,6 +610,78 @@ framework to set up sysfs files for this region. Simply leave it alone. </para> </sect1> +<sect1 id="using_uio_pdrv"> +<title>Using uio_pdrv for platform devices</title> + <para> + In many cases, UIO drivers for platform devices can be handled in a + generic way. In the same place where you define your + <varname>struct platform_device</varname>, you simply also implement + your interrupt handler and fill your + <varname>struct uio_info</varname>. A pointer to this + <varname>struct uio_info</varname> is then used as + <varname>platform_data</varname> for your platform device. + </para> + <para> + You also need to set up an array of <varname>struct resource</varname> + containing addresses and sizes of your memory mappings. This + information is passed to the driver using the + <varname>.resource</varname> and <varname>.num_resources</varname> + elements of <varname>struct platform_device</varname>. + </para> + <para> + You now have to set the <varname>.name</varname> element of + <varname>struct platform_device</varname> to + <varname>"uio_pdrv"</varname> to use the generic UIO platform device + driver. This driver will fill the <varname>mem[]</varname> array + according to the resources given, and register the device. + </para> + <para> + The advantage of this approach is that you only have to edit a file + you need to edit anyway. You do not have to create an extra driver. + </para> +</sect1> + +<sect1 id="using_uio_pdrv_genirq"> +<title>Using uio_pdrv_genirq for platform devices</title> + <para> + Especially in embedded devices, you frequently find chips where the + irq pin is tied to its own dedicated interrupt line. In such cases, + where you can be really sure the interrupt is not shared, we can take + the concept of <varname>uio_pdrv</varname> one step further and use a + generic interrupt handler. That's what + <varname>uio_pdrv_genirq</varname> does. + </para> + <para> + The setup for this driver is the same as described above for + <varname>uio_pdrv</varname>, except that you do not implement an + interrupt handler. The <varname>.handler</varname> element of + <varname>struct uio_info</varname> must remain + <varname>NULL</varname>. The <varname>.irq_flags</varname> element + must not contain <varname>IRQF_SHARED</varname>. + </para> + <para> + You will set the <varname>.name</varname> element of + <varname>struct platform_device</varname> to + <varname>"uio_pdrv_genirq"</varname> to use this driver. + </para> + <para> + The generic interrupt handler of <varname>uio_pdrv_genirq</varname> + will simply disable the interrupt line using + <function>disable_irq_nosync()</function>. After doing its work, + userspace can reenable the interrupt by writing 0x00000001 to the UIO + device file. The driver already implements an + <function>irq_control()</function> to make this possible, you must not + implement your own. + </para> + <para> + Using <varname>uio_pdrv_genirq</varname> not only saves a few lines of + interrupt handler code. You also do not need to know anything about + the chip's internal registers to create the kernel part of the driver. + All you need to know is the irq number of the pin the chip is + connected to. + </para> +</sect1> + </chapter> <chapter id="userspace_driver" xreflabel="Writing a driver in user space"> diff --git a/Documentation/IO-mapping.txt b/Documentation/IO-mapping.txt index 86edb61bdee..78a440695e1 100644 --- a/Documentation/IO-mapping.txt +++ b/Documentation/IO-mapping.txt @@ -1,6 +1,6 @@ [ NOTE: The virt_to_bus() and bus_to_virt() functions have been - superseded by the functionality provided by the PCI DMA - interface (see Documentation/DMA-mapping.txt). They continue + superseded by the functionality provided by the PCI DMA interface + (see Documentation/PCI/PCI-DMA-mapping.txt). They continue to be documented below for historical purposes, but new code must not use them. --davidm 00/12/12 ] diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c index cc49400b4af..7ea231172c8 100644 --- a/Documentation/accounting/getdelays.c +++ b/Documentation/accounting/getdelays.c @@ -392,6 +392,10 @@ int main(int argc, char *argv[]) goto err; } } + if (!maskset && !tid && !containerset) { + usage(); + goto err; + } do { int i; diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 3c5434c83da..ecad6ee7570 100644 --- a/Documentation/block/biodoc.txt +++ b/Documentation/block/biodoc.txt @@ -186,8 +186,9 @@ a virtual address mapping (unlike the earlier scheme of virtual address do not have a corresponding kernel virtual address space mapping) and low-memory pages. -Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA -aspects and mapping of scatter gather lists, and support for 64 bit PCI. +Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion +on PCI high mem DMA aspects and mapping of scatter gather lists, and support +for 64 bit PCI. Special handling is required only for cases where i/o needs to happen on pages at physical memory addresses beyond what the device can support. In these @@ -953,14 +954,14 @@ elevator_allow_merge_fn called whenever the block layer determines results in some sort of conflict internally, this hook allows it to do that. -elevator_dispatch_fn fills the dispatch queue with ready requests. +elevator_dispatch_fn* fills the dispatch queue with ready requests. I/O schedulers are free to postpone requests by not filling the dispatch queue unless @force is non-zero. Once dispatched, I/O schedulers are not allowed to manipulate the requests - they belong to generic dispatch queue. -elevator_add_req_fn called to add a new request into the scheduler +elevator_add_req_fn* called to add a new request into the scheduler elevator_queue_empty_fn returns true if the merge queue is empty. Drivers shouldn't use this, but rather check @@ -990,7 +991,7 @@ elevator_activate_req_fn Called when device driver first sees a request. elevator_deactivate_req_fn Called when device driver decides to delay a request by requeueing it. -elevator_init_fn +elevator_init_fn* elevator_exit_fn Allocate and free any elevator specific storage for a queue. diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index e33ee74eee7..d9e5d6f41b9 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -1,7 +1,8 @@ CGROUPS ------- -Written by Paul Menage <menage@google.com> based on Documentation/cpusets.txt +Written by Paul Menage <menage@google.com> based on +Documentation/cgroups/cpusets.txt Original copyright statements from cpusets.txt: Portions Copyright (C) 2004 BULL SA. @@ -68,7 +69,7 @@ On their own, the only use for cgroups is for simple job tracking. The intention is that other subsystems hook into the generic cgroup support to provide new attributes for cgroups, such as accounting/limiting the resources which processes in a cgroup can -access. For example, cpusets (see Documentation/cpusets.txt) allows +access. For example, cpusets (see Documentation/cgroups/cpusets.txt) allows you to associate a set of CPUs and a set of memory nodes with the tasks in each cgroup. diff --git a/Documentation/controllers/cpuacct.txt b/Documentation/cgroups/cpuacct.txt index bb775fbe43d..bb775fbe43d 100644 --- a/Documentation/controllers/cpuacct.txt +++ b/Documentation/cgroups/cpuacct.txt diff --git a/Documentation/cpusets.txt b/Documentation/cgroups/cpusets.txt index 5c86c258c79..5c86c258c79 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cgroups/cpusets.txt diff --git a/Documentation/controllers/devices.txt b/Documentation/cgroups/devices.txt index 7cc6e6a6067..7cc6e6a6067 100644 --- a/Documentation/controllers/devices.txt +++ b/Documentation/cgroups/devices.txt diff --git a/Documentation/controllers/memcg_test.txt b/Documentation/cgroups/memcg_test.txt index 08d4d3ea0d7..523a9c16c40 100644 --- a/Documentation/controllers/memcg_test.txt +++ b/Documentation/cgroups/memcg_test.txt @@ -1,12 +1,12 @@ Memory Resource Controller(Memcg) Implementation Memo. -Last Updated: 2008/12/15 -Base Kernel Version: based on 2.6.28-rc8-mm. +Last Updated: 2009/1/19 +Base Kernel Version: based on 2.6.29-rc2. Because VM is getting complex (one of reasons is memcg...), memcg's behavior is complex. This is a document for memcg's internal behavior. Please note that implementation details can be changed. -(*) Topics on API should be in Documentation/controllers/memory.txt) +(*) Topics on API should be in Documentation/cgroups/memory.txt) 0. How to record usage ? 2 objects are used. @@ -340,3 +340,23 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y. # mount -t cgroup none /cgroup -t cpuset,memory,cpu,devices and do task move, mkdir, rmdir etc...under this. + + 9.7 swapoff. + Besides management of swap is one of complicated parts of memcg, + call path of swap-in at swapoff is not same as usual swap-in path.. + It's worth to be tested explicitly. + + For example, test like following is good. + (Shell-A) + # mount -t cgroup none /cgroup -t memory + # mkdir /cgroup/test + # echo 40M > /cgroup/test/memory.limit_in_bytes + # echo 0 > /cgroup/test/tasks + Run malloc(100M) program under this. You'll see 60M of swaps. + (Shell-B) + # move all tasks in /cgroup/test to /cgroup + # /sbin/swapoff -a + # rmdir /test/cgroup + # kill malloc task. + + Of course, tmpfs v.s. swapoff test should be tested, too. diff --git a/Documentation/controllers/memory.txt b/Documentation/cgroups/memory.txt index e1501964df1..e1501964df1 100644 --- a/Documentation/controllers/memory.txt +++ b/Documentation/cgroups/memory.txt diff --git a/Documentation/controllers/resource_counter.txt b/Documentation/cgroups/resource_counter.txt index f196ac1d7d2..f196ac1d7d2 100644 --- a/Documentation/controllers/resource_counter.txt +++ b/Documentation/cgroups/resource_counter.txt diff --git a/Documentation/crypto/async-tx-api.txt b/Documentation/crypto/async-tx-api.txt index c1e9545c59b..9f59fcbf5d8 100644 --- a/Documentation/crypto/async-tx-api.txt +++ b/Documentation/crypto/async-tx-api.txt @@ -13,9 +13,9 @@ 3.6 Constraints 3.7 Example -4 DRIVER DEVELOPER NOTES +4 DMAENGINE DRIVER DEVELOPER NOTES 4.1 Conformance points -4.2 "My application needs finer control of hardware channels" +4.2 "My application needs exclusive control of hardware channels" 5 SOURCE @@ -150,6 +150,7 @@ ops_run_* and ops_complete_* routines in drivers/md/raid5.c for more implementation examples. 4 DRIVER DEVELOPMENT NOTES + 4.1 Conformance points: There are a few conformance points required in dmaengine drivers to accommodate assumptions made by applications using the async_tx API: @@ -158,58 +159,49 @@ accommodate assumptions made by applications using the async_tx API: 3/ Use async_tx_run_dependencies() in the descriptor clean up path to handle submission of dependent operations -4.2 "My application needs finer control of hardware channels" -This requirement seems to arise from cases where a DMA engine driver is -trying to support device-to-memory DMA. The dmaengine and async_tx -implementations were designed for offloading memory-to-memory -operations; however, there are some capabilities of the dmaengine layer -that can be used for platform-specific channel management. -Platform-specific constraints can be handled by registering the -application as a 'dma_client' and implementing a 'dma_event_callback' to -apply a filter to the available channels in the system. Before showing -how to implement a custom dma_event callback some background of -dmaengine's client support is required. - -The following routines in dmaengine support multiple clients requesting -use of a channel: -- dma_async_client_register(struct dma_client *client) -- dma_async_client_chan_request(struct dma_client *client) - -dma_async_client_register takes a pointer to an initialized dma_client -structure. It expects that the 'event_callback' and 'cap_mask' fields -are already initialized. - -dma_async_client_chan_request triggers dmaengine to notify the client of -all channels that satisfy the capability mask. It is up to the client's -event_callback routine to track how many channels the client needs and -how many it is currently using. The dma_event_callback routine returns a -dma_state_client code to let dmaengine know the status of the -allocation. - -Below is the example of how to extend this functionality for -platform-specific filtering of the available channels beyond the -standard capability mask: - -static enum dma_state_client -my_dma_client_callback(struct dma_client *client, - struct dma_chan *chan, enum dma_state state) -{ - struct dma_device *dma_dev; - struct my_platform_specific_dma *plat_dma_dev; - - dma_dev = chan->device; - plat_dma_dev = container_of(dma_dev, - struct my_platform_specific_dma, - dma_dev); - - if (!plat_dma_dev->platform_specific_capability) - return DMA_DUP; - - . . . -} +4.2 "My application needs exclusive control of hardware channels" +Primarily this requirement arises from cases where a DMA engine driver +is being used to support device-to-memory operations. A channel that is +performing these operations cannot, for many platform specific reasons, +be shared. For these cases the dma_request_channel() interface is +provided. + +The interface is: +struct dma_chan *dma_request_channel(dma_cap_mask_t mask, + dma_filter_fn filter_fn, + void *filter_param); + +Where dma_filter_fn is defined as: +typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); + +When the optional 'filter_fn' parameter is set to NULL +dma_request_channel simply returns the first channel that satisfies the +capability mask. Otherwise, when the mask parameter is insufficient for +specifying the necessary channel, the filter_fn routine can be used to +disposition the available channels in the system. The filter_fn routine +is called once for each free channel in the system. Upon seeing a +suitable channel filter_fn returns DMA_ACK which flags that channel to +be the return value from dma_request_channel. A channel allocated via +this interface is exclusive to the caller, until dma_release_channel() +is called. + +The DMA_PRIVATE capability flag is used to tag dma devices that should +not be used by the general-purpose allocator. It can be set at +initialization time if it is known that a channel will always be +private. Alternatively, it is set when dma_request_channel() finds an +unused "public" channel. + +A couple caveats to note when implementing a driver and consumer: +1/ Once a channel has been privately allocated it will no longer be + considered by the general-purpose allocator even after a call to + dma_release_channel(). +2/ Since capabilities are specified at the device level a dma_device + with multiple channels will either have all channels public, or all + channels private. 5 SOURCE -include/linux/dmaengine.h: core header file for DMA drivers and clients + +include/linux/dmaengine.h: core header file for DMA drivers and api users drivers/dma/dmaengine.c: offload engine channel management routines drivers/dma/: location for offload engine drivers include/linux/async_tx.h: core header file for the async_tx api diff --git a/Documentation/dmaengine.txt b/Documentation/dmaengine.txt new file mode 100644 index 00000000000..0c1c2f63c0a --- /dev/null +++ b/Documentation/dmaengine.txt @@ -0,0 +1 @@ +See Documentation/crypto/async-tx-api.txt diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index cfbfa15a46b..ec6a9392a17 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -97,8 +97,8 @@ prototypes: void (*put_super) (struct super_block *); void (*write_super) (struct super_block *); int (*sync_fs)(struct super_block *sb, int wait); - void (*write_super_lockfs) (struct super_block *); - void (*unlockfs) (struct super_block *); + int (*freeze_fs) (struct super_block *); + int (*unfreeze_fs) (struct super_block *); int (*statfs) (struct dentry *, struct kstatfs *); int (*remount_fs) (struct super_block *, int *, char *); void (*clear_inode) (struct inode *); @@ -119,8 +119,8 @@ delete_inode: no put_super: yes yes no write_super: no yes read sync_fs: no no read -write_super_lockfs: ? -unlockfs: ? +freeze_fs: ? +unfreeze_fs: ? statfs: no no no remount_fs: yes yes maybe (see below) clear_inode: no diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt new file mode 100644 index 00000000000..64087c34327 --- /dev/null +++ b/Documentation/filesystems/btrfs.txt @@ -0,0 +1,91 @@ + + BTRFS + ===== + +Btrfs is a new copy on write filesystem for Linux aimed at +implementing advanced features while focusing on fault tolerance, +repair and easy administration. Initially developed by Oracle, Btrfs +is licensed under the GPL and open for contribution from anyone. + +Linux has a wealth of filesystems to choose from, but we are facing a +number of challenges with scaling to the large storage subsystems that +are becoming common in today's data centers. Filesystems need to scale +in their ability to address and manage large storage, and also in +their ability to detect, repair and tolerate errors in the data stored +on disk. Btrfs is under heavy development, and is not suitable for +any uses other than benchmarking and review. The Btrfs disk format is +not yet finalized. + +The main Btrfs features include: + + * Extent based file storage (2^64 max file size) + * Space efficient packing of small files + * Space efficient indexed directories + * Dynamic inode allocation + * Writable snapshots + * Subvolumes (separate internal filesystem roots) + * Object level mirroring and striping + * Checksums on data and metadata (multiple algorithms available) + * Compression + * Integrated multiple device support, with several raid algorithms + * Online filesystem check (not yet implemented) + * Very fast offline filesystem check + * Efficient incremental backup and FS mirroring (not yet implemented) + * Online filesystem defragmentation + + + + MAILING LIST + ============ + +There is a Btrfs mailing list hosted on vger.kernel.org. You can +find details on how to subscribe here: + +http://vger.kernel.org/vger-lists.html#linux-btrfs + +Mailing list archives are available from gmane: + +http://dir.gmane.org/gmane.comp.file-systems.btrfs + + + + IRC + === + +Discussion of Btrfs also occurs on the #btrfs channel of the Freenode +IRC network. + + + + UTILITIES + ========= + +Userspace tools for creating and manipulating Btrfs file systems are +available from the git repository at the following location: + + http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs-unstable.git + git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs-unstable.git + +These include the following tools: + +mkfs.btrfs: create a filesystem + +btrfsctl: control program to create snapshots and subvolumes: + + mount /dev/sda2 /mnt + btrfsctl -s new_subvol_name /mnt + btrfsctl -s snapshot_of_default /mnt/default + btrfsctl -s snapshot_of_new_subvol /mnt/new_subvol_name + btrfsctl -s snapshot_of_a_snapshot /mnt/snapshot_of_new_subvol + ls /mnt + default snapshot_of_a_snapshot snapshot_of_new_subvol + new_subvol_name snapshot_of_default + + Snapshots and subvolumes cannot be deleted right now, but you can + rm -rf all the files and directories inside them. + +btrfsck: do a limited check of the FS extent trees. + +btrfs-debug-tree: print all of the FS metadata in text form. Example: + + btrfs-debug-tree /dev/sda2 >& big_output_file diff --git a/Documentation/filesystems/nfs-rdma.txt b/Documentation/filesystems/nfs-rdma.txt index 44bd766f2e5..85eaeaddd27 100644 --- a/Documentation/filesystems/nfs-rdma.txt +++ b/Documentation/filesystems/nfs-rdma.txt @@ -251,7 +251,7 @@ NFS/RDMA Setup Instruct the server to listen on the RDMA transport: - $ echo rdma 2050 > /proc/fs/nfsd/portlist + $ echo rdma 20049 > /proc/fs/nfsd/portlist - On the client system @@ -263,7 +263,7 @@ NFS/RDMA Setup Regardless of how the client was built (module or built-in), use this command to mount the NFS/RDMA server: - $ mount -o rdma,port=2050 <IPoIB-server-name-or-address>:/<export> /mnt + $ mount -o rdma,port=20049 <IPoIB-server-name-or-address>:/<export> /mnt To verify that the mount is using RDMA, run "cat /proc/mounts" and check the "proto" field for the given mount. diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index d105eb45282..a87be42f821 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -1371,292 +1371,8 @@ auto_msgmni default value is 1. 2.4 /proc/sys/vm - The virtual memory subsystem ----------------------------------------------- -The files in this directory can be used to tune the operation of the virtual -memory (VM) subsystem of the Linux kernel. - -vfs_cache_pressure ------------------- - -Controls the tendency of the kernel to reclaim the memory which is used for -caching of directory and inode objects. - -At the default value of vfs_cache_pressure=100 the kernel will attempt to -reclaim dentries and inodes at a "fair" rate with respect to pagecache and -swapcache reclaim. Decreasing vfs_cache_pressure causes the kernel to prefer -to retain dentry and inode caches. Increasing vfs_cache_pressure beyond 100 -causes the kernel to prefer to reclaim dentries and inodes. - -dirty_background_bytes ----------------------- - -Contains the amount of dirty memory at which the pdflush background writeback -daemon will start writeback. - -If dirty_background_bytes is written, dirty_background_ratio becomes a function -of its value (dirty_background_bytes / the amount of dirtyable system memory). - -dirty_background_ratio ----------------------- - -Contains, as a percentage of the dirtyable system memory (free pages + mapped -pages + file cache, not including locked pages and HugePages), the number of -pages at which the pdflush background writeback daemon will start writing out -dirty data. - -If dirty_background_ratio is written, dirty_background_bytes becomes a function -of its value (dirty_background_ratio * the amount of dirtyable system memory). - -dirty_bytes ------------ - -Contains the amount of dirty memory at which a process generating disk writes -will itself start writeback. - -If dirty_bytes is written, dirty_ratio becomes a function of its value -(dirty_bytes / the amount of dirtyable system memory). - -dirty_ratio ------------ - -Contains, as a percentage of the dirtyable system memory (free pages + mapped -pages + file cache, not including locked pages and HugePages), the number of -pages at which a process which is generating disk writes will itself start -writing out dirty data. - -If dirty_ratio is written, dirty_bytes becomes a function of its value -(dirty_ratio * the amount of dirtyable system memory). - -dirty_writeback_centisecs -------------------------- - -The pdflush writeback daemons will periodically wake up and write `old' data -out to disk. This tunable expresses the interval between those wakeups, in -100'ths of a second. - -Setting this to zero disables periodic writeback altogether. - -dirty_expire_centisecs ----------------------- - -This tunable is used to define when dirty data is old enough to be eligible -for writeout by the pdflush daemons. It is expressed in 100'ths of a second. -Data which has been dirty in-memory for longer than this interval will be -written out next time a pdflush daemon wakes up. - -highmem_is_dirtyable --------------------- - -Only present if CONFIG_HIGHMEM is set. - -This defaults to 0 (false), meaning that the ratios set above are calculated -as a percentage of lowmem only. This protects against excessive scanning -in page reclaim, swapping and general VM distress. - -Setting this to 1 can be useful on 32 bit machines where you want to make -random changes within an MMAPed file that is larger than your available -lowmem without causing large quantities of random IO. Is is safe if the -behavior of all programs running on the machine is known and memory will -not be otherwise stressed. - -legacy_va_layout ----------------- - -If non-zero, this sysctl disables the new 32-bit mmap mmap layout - the kernel -will use the legacy (2.4) layout for all processes. - -lowmem_reserve_ratio ---------------------- - -For some specialised workloads on highmem machines it is dangerous for -the kernel to allow process memory to be allocated from the "lowmem" -zone. This is because that memory could then be pinned via the mlock() -system call, or by unavailability of swapspace. - -And on large highmem machines this lack of reclaimable lowmem memory -can be fatal. - -So the Linux page allocator has a mechanism which prevents allocations -which _could_ use highmem from using too much lowmem. This means that -a certain amount of lowmem is defended from the possibility of being -captured into pinned user memory. - -(The same argument applies to the old 16 megabyte ISA DMA region. This -mechanism will also defend that region from allocations which could use -highmem or lowmem). - -The `lowmem_reserve_ratio' tunable determines how aggressive the kernel is -in defending these lower zones. - -If you have a machine which uses highmem or ISA DMA and your -applications are using mlock(), or if you are running with no swap then -you probably should change the lowmem_reserve_ratio setting. - -The lowmem_reserve_ratio is an array. You can see them by reading this file. -- -% cat /proc/sys/vm/lowmem_reserve_ratio -256 256 32 -- -Note: # of this elements is one fewer than number of zones. Because the highest - zone's value is not necessary for following calculation. - -But, these values are not used directly. The kernel calculates # of protection -pages for each zones from them. These are shown as array of protection pages -in /proc/zoneinfo like followings. (This is an example of x86-64 box). -Each zone has an array of protection pages like this. - -- -Node 0, zone DMA - pages free 1355 - min 3 - low 3 - high 4 - : - : - numa_other 0 - protection: (0, 2004, 2004, 2004) - ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - pagesets - cpu: 0 pcp: 0 - : -- -These protections are added to score to judge whether this zone should be used -for page allocation or should be reclaimed. - -In this example, if normal pages (index=2) are required to this DMA zone and -pages_high is used for watermark, the kernel judges this zone should not be -used because pages_free(1355) is smaller than watermark + protection[2] -(4 + 2004 = 2008). If this protection value is 0, this zone would be used for -normal page requirement. If requirement is DMA zone(index=0), protection[0] -(=0) is used. - -zone[i]'s protection[j] is calculated by following expression. - -(i < j): - zone[i]->protection[j] - = (total sums of present_pages from zone[i+1] to zone[j] on the node) - / lowmem_reserve_ratio[i]; -(i = j): - (should not be protected. = 0; -(i > j): - (not necessary, but looks 0) - -The default values of lowmem_reserve_ratio[i] are - 256 (if zone[i] means DMA or DMA32 zone) - 32 (others). -As above expression, they are reciprocal number of ratio. -256 means 1/256. # of protection pages becomes about "0.39%" of total present -pages of higher zones on the node. - -If you would like to protect more pages, smaller values are effective. -The minimum value is 1 (1/1 -> 100%). - -page-cluster ------------- - -page-cluster controls the number of pages which are written to swap in -a single attempt. The swap I/O size. - -It is a logarithmic value - setting it to zero means "1 page", setting -it to 1 means "2 pages", setting it to 2 means "4 pages", etc. - -The default value is three (eight pages at a time). There may be some -small benefits in tuning this to a different value if your workload is -swap-intensive. - -overcommit_memory ------------------ - -Controls overcommit of system memory, possibly allowing processes -to allocate (but not use) more memory than is actually available. - - -0 - Heuristic overcommit handling. Obvious overcommits of - address space are refused. Used for a typical system. It - ensures a seriously wild allocation fails while allowing - overcommit to reduce swap usage. root is allowed to - allocate slightly more memory in this mode. This is the - default. - -1 - Always overcommit. Appropriate for some scientific - applications. - -2 - Don't overcommit. The total address space commit - for the system is not permitted to exceed swap plus a - configurable percentage (default is 50) of physical RAM. - Depending on the percentage you use, in most situations - this means a process will not be killed while attempting - to use already-allocated memory but will receive errors - on memory allocation as appropriate. - -overcommit_ratio ----------------- - -Percentage of physical memory size to include in overcommit calculations -(see above.) - -Memory allocation limit = swapspace + physmem * (overcommit_ratio / 100) - - swapspace = total size of all swap areas - physmem = size of physical memory in system - -nr_hugepages and hugetlb_shm_group ----------------------------------- - -nr_hugepages configures number of hugetlb page reserved for the system. - -hugetlb_shm_group contains group id that is allowed to create SysV shared -memory segment using hugetlb page. - -hugepages_treat_as_movable --------------------------- - -This parameter is only useful when kernelcore= is specified at boot time to -create ZONE_MOVABLE for pages that may be reclaimed or migrated. Huge pages -are not movable so are not normally allocated from ZONE_MOVABLE. A non-zero -value written to hugepages_treat_as_movable allows huge pages to be allocated -from ZONE_MOVABLE. - -Once enabled, the ZONE_MOVABLE is treated as an area of memory the huge -pages pool can easily grow or shrink within. Assuming that applications are -not running that mlock() a lot of memory, it is likely the huge pages pool -can grow to the size of ZONE_MOVABLE by repeatedly entering the desired value -into nr_hugepages and triggering page reclaim. - -laptop_mode ------------ - -laptop_mode is a knob that controls "laptop mode". All the things that are -controlled by this knob are discussed in Documentation/laptops/laptop-mode.txt. - -block_dump ----------- - -block_dump enables block I/O debugging when set to a nonzero value. More -information on block I/O debugging is in Documentation/laptops/laptop-mode.txt. - -swap_token_timeout ------------------- - -This file contains valid hold time of swap out protection token. The Linux -VM has token based thrashing control mechanism and uses the token to prevent -unnecessary page faults in thrashing situation. The unit of the value is -second. The value would be useful to tune thrashing behavior. - -drop_caches ------------ - -Writing to this will cause the kernel to drop clean caches, dentries and -inodes from memory, causing that memory to become free. - -To free pagecache: - echo 1 > /proc/sys/vm/drop_caches -To free dentries and inodes: - echo 2 > /proc/sys/vm/drop_caches -To free pagecache, dentries and inodes: - echo 3 > /proc/sys/vm/drop_caches - -As this is a non-destructive operation and dirty objects are not freeable, the -user should run `sync' first. +Please see: Documentation/sysctls/vm.txt for a description of these +entries. 2.5 /proc/sys/dev - Device specific parameters @@ -2311,6 +2027,34 @@ increase the likelihood of this process being killed by the oom-killer. Valid values are in the range -16 to +15, plus the special value -17, which disables oom-killing altogether for this process. +The process to be killed in an out-of-memory situation is selected among all others +based on its badness score. This value equals the original memory size of the process +and is then updated according to its CPU time (utime + stime) and the +run time (uptime - start time). The longer it runs the smaller is the score. +Badness score is divided by the square root of the CPU time and then by +the double square root of the run time. + +Swapped out tasks are killed first. Half of each child's memory size is added to +the parent's score if they do not share the same memory. Thus forking servers +are the prime candidates to be killed. Having only one 'hungry' child will make +parent less preferable than the child. + +/proc/<pid>/oom_score shows process' current badness score. + +The following heuristics are then applied: + * if the task was reniced, its score doubles + * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE + or CAP_SYS_RAWIO) have their score divided by 4 + * if oom condition happened in one cpuset and checked task does not belong + to it, its score is divided by 8 + * the resulting score is multiplied by two to the power of oom_adj, i.e. + points <<= oom_adj when it is positive and + points >>= -(oom_adj) otherwise + +The task with the highest badness score is then selected and its children +are killed, process itself will be killed in an OOM situation when it does +not have children or some of them disabled oom like described above. + 2.13 /proc/<pid>/oom_score - Display current oom-killer score ------------------------------------------------------------- diff --git a/Documentation/filesystems/squashfs.txt b/Documentation/filesystems/squashfs.txt new file mode 100644 index 00000000000..3e79e4a7a39 --- /dev/null +++ b/Documentation/filesystems/squashfs.txt @@ -0,0 +1,225 @@ +SQUASHFS 4.0 FILESYSTEM +======================= + +Squashfs is a compressed read-only filesystem for Linux. +It uses zlib compression to compress files, inodes and directories. +Inodes in the system are very small and all blocks are packed to minimise +data overhead. Block sizes greater than 4K are supported up to a maximum +of 1Mbytes (default block size 128K). + +Squashfs is intended for general read-only filesystem use, for archival +use (i.e. in cases where a .tar.gz file may be used), and in constrained +block device/memory systems (e.g. embedded systems) where low overhead is +needed. + +Mailing list: squashfs-devel@lists.sourceforge.net +Web site: www.squashfs.org + +1. FILESYSTEM FEATURES +---------------------- + +Squashfs filesystem features versus Cramfs: + + Squashfs Cramfs + +Max filesystem size: 2^64 16 MiB +Max file size: ~ 2 TiB 16 MiB +Max files: unlimited unlimited +Max directories: unlimited unlimited +Max entries per directory: unlimited unlimited +Max block size: 1 MiB 4 KiB +Metadata compression: yes no +Directory indexes: yes no +Sparse file support: yes no +Tail-end packing (fragments): yes no +Exportable (NFS etc.): yes no +Hard link support: yes no +"." and ".." in readdir: yes no +Real inode numbers: yes no +32-bit uids/gids: yes no +File creation time: yes no +Xattr and ACL support: no no + +Squashfs compresses data, inodes and directories. In addition, inode and +directory data are highly compacted, and packed on byte boundaries. Each +compressed inode is on average 8 bytes in length (the exact length varies on +file type, i.e. regular file, directory, symbolic link, and block/char device +inodes have different sizes). + +2. USING SQUASHFS +----------------- + +As squashfs is a read-only filesystem, the mksquashfs program must be used to +create populated squashfs filesystems. This and other squashfs utilities +can be obtained from http://www.squashfs.org. Usage instructions can be +obtained from this site also. + + +3. SQUASHFS FILESYSTEM DESIGN +----------------------------- + +A squashfs filesystem consists of seven parts, packed together on a byte +alignment: + + --------------- + | superblock | + |---------------| + | datablocks | + | & fragments | + |---------------| + | inode table | + |---------------| + | directory | + | table | + |---------------| + | fragment | + | table | + |---------------| + | export | + | table | + |---------------| + | uid/gid | + | lookup table | + --------------- + +Compressed data blocks are written to the filesystem as files are read from +the source directory, and checked for duplicates. Once all file data has been +written the completed inode, directory, fragment, export and uid/gid lookup +tables are written. + +3.1 Inodes +---------- + +Metadata (inodes and directories) are compressed in 8Kbyte blocks. Each +compressed block is prefixed by a two byte length, the top bit is set if the +block is uncompressed. A block will be uncompressed if the -noI option is set, +or if the compressed block was larger than the uncompressed block. + +Inodes are packed into the metadata blocks, and are not aligned to block +boundaries, therefore inodes overlap compressed blocks. Inodes are identified +by a 48-bit number which encodes the location of the compressed metadata block +containing the inode, and the byte offset into that block where the inode is +placed (<block, offset>). + +To maximise compression there are different inodes for each file type +(regular file, directory, device, etc.), the inode contents and length +varying with the type. + +To further maximise compression, two types of regular file inode and +directory inode are defined: inodes optimised for frequently occurring +regular files and directories, and extended types where extra +information has to be stored. + +3.2 Directories +--------------- + +Like inodes, directories are packed into compressed metadata blocks, stored +in a directory table. Directories are accessed using the start address of +the metablock containing the directory and the offset into the +decompressed block (<block, offset>). + +Directories are organised in a slightly complex way, and are not simply +a list of file names. The organisation takes advantage of the +fact that (in most cases) the inodes of the files will be in the same +compressed metadata block, and therefore, can share the start block. +Directories are therefore organised in a two level list, a directory +header containing the shared start block value, and a sequence of directory +entries, each of which share the shared start block. A new directory header +is written once/if the inode start block changes. The directory +header/directory entry list is repeated as many times as necessary. + +Directories are sorted, and can contain a directory index to speed up +file lookup. Directory indexes store one entry per metablock, each entry +storing the index/filename mapping to the first directory header +in each metadata block. Directories are sorted in alphabetical order, +and at lookup the index is scanned linearly looking for the first filename +alphabetically larger than the filename being looked up. At this point the +location of the metadata block the filename is in has been found. +The general idea of the index is ensure only one metadata block needs to be +decompressed to do a lookup irrespective of the length of the directory. +This scheme has the advantage that it doesn't require extra memory overhead +and doesn't require much extra storage on disk. + +3.3 File data +------------- + +Regular files consist of a sequence of contiguous compressed blocks, and/or a +compressed fragment block (tail-end packed block). The compressed size +of each datablock is stored in a block list contained within the +file inode. + +To speed up access to datablocks when reading 'large' files (256 Mbytes or +larger), the code implements an index cache that caches the mapping from +block index to datablock location on disk. + +The index cache allows Squashfs to handle large files (up to 1.75 TiB) while +retaining a simple and space-efficient block list on disk. The cache +is split into slots, caching up to eight 224 GiB files (128 KiB blocks). +Larger files use multiple slots, with 1.75 TiB files using all 8 slots. +The index cache is designed to be memory efficient, and by default uses +16 KiB. + +3.4 Fragment lookup table +------------------------- + +Regular files can contain a fragment index which is mapped to a fragment +location on disk and compressed size using a fragment lookup table. This +fragment lookup table is itself stored compressed into metadata blocks. +A second index table is used to locate these. This second index table for +speed of access (and because it is small) is read at mount time and cached +in memory. + +3.5 Uid/gid lookup table +------------------------ + +For space efficiency regular files store uid and gid indexes, which are +converted to 32-bit uids/gids using an id look up table. This table is +stored compressed into metadata blocks. A second index table is used to +locate these. This second index table for speed of access (and because it +is small) is read at mount time and cached in memory. + +3.6 Export table +---------------- + +To enable Squashfs filesystems to be exportable (via NFS etc.) filesystems +can optionally (disabled with the -no-exports Mksquashfs option) contain +an inode number to inode disk location lookup table. This is required to +enable Squashfs to map inode numbers passed in filehandles to the inode +location on disk, which is necessary when the export code reinstantiates +expired/flushed inodes. + +This table is stored compressed into metadata blocks. A second index table is +used to locate these. This second index table for speed of access (and because +it is small) is read at mount time and cached in memory. + + +4. TODOS AND OUTSTANDING ISSUES +------------------------------- + +4.1 Todo list +------------- + +Implement Xattr and ACL support. The Squashfs 4.0 filesystem layout has hooks +for these but the code has not been written. Once the code has been written +the existing layout should not require modification. + +4.2 Squashfs internal cache +--------------------------- + +Blocks in Squashfs are compressed. To avoid repeatedly decompressing +recently accessed data Squashfs uses two small metadata and fragment caches. + +The cache is not used for file datablocks, these are decompressed and cached in +the page-cache in the normal way. The cache is used to temporarily cache +fragment and metadata blocks which have been read as a result of a metadata +(i.e. inode or directory) or fragment access. Because metadata and fragments +are packed together into blocks (to gain greater compression) the read of a +particular piece of metadata or fragment will retrieve other metadata/fragments +which have been packed with it, these because of locality-of-reference may be +read in the near future. Temporarily caching them ensures they are available +for near future access without requiring an additional read and decompress. + +In the future this internal cache may be replaced with an implementation which +uses the kernel page cache. Because the page cache operates on page sized +units this may introduce additional complexity in terms of locking and +associated race conditions. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index ef19afa186a..deeeed0faa8 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -210,8 +210,8 @@ struct super_operations { void (*put_super) (struct super_block *); void (*write_super) (struct super_block *); int (*sync_fs)(struct super_block *sb, int wait); - void (*write_super_lockfs) (struct super_block *); - void (*unlockfs) (struct super_block *); + int (*freeze_fs) (struct super_block *); + int (*unfreeze_fs) (struct super_block *); int (*statfs) (struct dentry *, struct kstatfs *); int (*remount_fs) (struct super_block *, int *, char *); void (*clear_inode) (struct inode *); @@ -270,11 +270,11 @@ or bottom half). a superblock. The second parameter indicates whether the method should wait until the write out has been completed. Optional. - write_super_lockfs: called when VFS is locking a filesystem and + freeze_fs: called when VFS is locking a filesystem and forcing it into a consistent state. This method is currently used by the Logical Volume Manager (LVM). - unlockfs: called when VFS is unlocking a filesystem and making it writable + unfreeze_fs: called when VFS is unlocking a filesystem and making it writable again. statfs: called when the VFS needs to get filesystem statistics. This diff --git a/Documentation/hwmon/adt7475 b/Documentation/hwmon/adt7475 new file mode 100644 index 00000000000..a2b1abec850 --- /dev/null +++ b/Documentation/hwmon/adt7475 @@ -0,0 +1,87 @@ +This describes the interface for the ADT7475 driver: + +(there are 4 fans, numbered fan1 to fan4): + +fanX_input Read the current speed of the fan (in RPMs) +fanX_min Read/write the minimum speed of the fan. Dropping + below this sets an alarm. + +(there are three PWMs, numbered pwm1 to pwm3): + +pwmX Read/write the current duty cycle of the PWM. Writes + only have effect when auto mode is turned off (see + below). Range is 0 - 255. + +pwmX_enable Fan speed control method: + + 0 - No control (fan at full speed) + 1 - Manual fan speed control (using pwm[1-*]) + 2 - Automatic fan speed control + +pwmX_auto_channels_temp Select which channels affect this PWM + + 1 - TEMP1 controls PWM + 2 - TEMP2 controls PWM + 4 - TEMP3 controls PWM + 6 - TEMP2 and TEMP3 control PWM + 7 - All three inputs control PWM + +pwmX_freq Read/write the PWM frequency in Hz. The number + should be one of the following: + + 11 Hz + 14 Hz + 22 Hz + 29 Hz + 35 Hz + 44 Hz + 58 Hz + 88 Hz + +pwmX_auto_point1_pwm Read/write the minimum PWM duty cycle in automatic mode + +pwmX_auto_point2_pwm Read/write the maximum PWM duty cycle in automatic mode + +(there are three temperature settings numbered temp1 to temp3): + +tempX_input Read the current temperature. The value is in milli + degrees of Celsius. + +tempX_max Read/write the upper temperature limit - exceeding this + will cause an alarm. + +tempX_min Read/write the lower temperature limit - exceeding this + will cause an alarm. + +tempX_offset Read/write the temperature adjustment offset + +tempX_crit Read/write the THERM limit for remote1. + +tempX_crit_hyst Set the temperature value below crit where the + fans will stay on - this helps drive the temperature + low enough so it doesn't stay near the edge and + cause THERM to keep tripping. + +tempX_auto_point1_temp Read/write the minimum temperature where the fans will + turn on in automatic mode. + +tempX_auto_point2_temp Read/write the maximum temperature over which the fans + will run in automatic mode. tempX_auto_point1_temp + and tempX_auto_point2_temp together define the + range of automatic control. + +tempX_alarm Read a 1 if the max/min alarm is set +tempX_fault Read a 1 if either temp1 or temp3 diode has a fault + +(There are two voltage settings, in1 and in2): + +inX_input Read the current voltage on VCC. Value is in + millivolts. + +inX_min read/write the minimum voltage limit. + Dropping below this causes an alarm. + +inX_max read/write the maximum voltage limit. + Exceeding this causes an alarm. + +inX_alarm Read a 1 if the max/min alarm is set. diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d index 65dfb0c0fd6..0fcfc4a7ccd 100644 --- a/Documentation/hwmon/lis3lv02d +++ b/Documentation/hwmon/lis3lv02d @@ -13,18 +13,21 @@ Author: Description ----------- -This driver provides support for the accelerometer found in various HP laptops -sporting the feature officially called "HP Mobile Data Protection System 3D" or -"HP 3D DriveGuard". It detect automatically laptops with this sensor. Known models -(for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will -have their axis automatically oriented on standard way (eg: you can directly -play neverball). The accelerometer data is readable via +This driver provides support for the accelerometer found in various HP +laptops sporting the feature officially called "HP Mobile Data +Protection System 3D" or "HP 3D DriveGuard". It detect automatically +laptops with this sensor. Known models (for now the HP 2133, nc6420, +nc2510, nc8510, nc84x0, nw9440 and nx9420) will have their axis +automatically oriented on standard way (eg: you can directly play +neverball). The accelerometer data is readable via /sys/devices/platform/lis3lv02d. Sysfs attributes under /sys/devices/platform/lis3lv02d/: position - 3D position that the accelerometer reports. Format: "(x,y,z)" -calibrate - read: values (x, y, z) that are used as the base for input class device operation. - write: forces the base to be recalibrated with the current position. +calibrate - read: values (x, y, z) that are used as the base for input + class device operation. + write: forces the base to be recalibrated with the current + position. rate - reports the sampling rate of the accelerometer device in HZ This driver also provides an absolute input class device, allowing @@ -39,11 +42,12 @@ the accelerometer are converted into a "standard" organisation of the axes * When the laptop is horizontal the position reported is about 0 for X and Y and a positive value for Z * If the left side is elevated, X increases (becomes positive) - * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative) + * If the front side (where the touchpad is) is elevated, Y decreases + (becomes negative) * If the laptop is put upside-down, Z becomes negative -If your laptop model is not recognized (cf "dmesg"), you can send an email to the -authors to add it to the database. When reporting a new laptop, please include -the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position -in these four cases. +If your laptop model is not recognized (cf "dmesg"), you can send an +email to the authors to add it to the database. When reporting a new +laptop, please include the output of "dmidecode" plus the value of +/sys/devices/platform/lis3lv02d/position in these four cases. diff --git a/Documentation/ja_JP/stable_kernel_rules.txt b/Documentation/ja_JP/stable_kernel_rules.txt index b3ffe870de3..14265837c4c 100644 --- a/Documentation/ja_JP/stable_kernel_rules.txt +++ b/Documentation/ja_JP/stable_kernel_rules.txt @@ -12,11 +12,11 @@ file at first. ================================== これは、 -linux-2.6.24/Documentation/stable_kernel_rules.txt +linux-2.6.29/Documentation/stable_kernel_rules.txt の和訳です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > -翻訳日： 2007/12/30 +翻訳日： 2009/1/14 翻訳者： Tsugikazu Shibata <tshibata at ab dot jp dot nec dot com> 校正者： 武井伸光さん、<takei at webmasters dot gr dot jp> かねこさん (Seiji Kaneko) <skaneko at a2 dot mbn dot or dot jp> @@ -38,12 +38,15 @@ linux-2.6.24/Documentation/stable_kernel_rules.txt - ビルドエラー(CONFIG_BROKENになっているものを除く), oops, ハング、デー タ破壊、現実のセキュリティ問題、その他 "ああ、これはダメだね"という ようなものを修正しなければならない。短く言えば、重大な問題。 + - 新しい device ID とクオークも受け入れられる。 - どのように競合状態が発生するかの説明も一緒に書かれていない限り、 "理論的には競合状態になる"ようなものは不可。 - いかなる些細な修正も含めることはできない。(スペルの修正、空白のクリー ンアップなど) - - 対応するサブシステムメンテナが受け入れたものでなければならない。 - Documentation/SubmittingPatches の規則に従ったものでなければならない。 + - パッチ自体か同等の修正が Linus のツリーに既に存在しなければならない。 + Linus のツリーでのコミットID を -stable へのパッチ投稿の際に引用す + ること。 -stable ツリーにパッチを送付する手続き- @@ -52,8 +55,10 @@ linux-2.6.24/Documentation/stable_kernel_rules.txt - 送信者はパッチがキューに受け付けられた際には ACK を、却下された場合 には NAK を受け取る。この反応は開発者たちのスケジュールによって、数 日かかる場合がある。 - - もし受け取られたら、パッチは他の開発者たちのレビューのために - -stable キューに追加される。 + - もし受け取られたら、パッチは他の開発者たちと関連するサブシステムの + メンテナーによるレビューのために -stable キューに追加される。 + - パッチに stable@kernel.org のアドレスが付加されているときには、それ + が Linus のツリーに入る時に自動的に stable チームに email される。 - セキュリティパッチはこのエイリアス (stable@kernel.org) に送られるべ きではなく、代わりに security@kernel.org のアドレスに送られる。 diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index 923f9ddee8f..f3355b6812d 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -3,7 +3,7 @@ Environment variables KCPPFLAGS -------------------------------------------------- Additional options to pass when preprocessing. The preprocessing options -will be used in all cases where kbuild do preprocessing including +will be used in all cases where kbuild does preprocessing including building C files and assembler files. KAFLAGS @@ -16,7 +16,7 @@ Additional options to the C compiler. KBUILD_VERBOSE -------------------------------------------------- -Set the kbuild verbosity. Can be assinged same values as "V=...". +Set the kbuild verbosity. Can be assigned same values as "V=...". See make help for the full list. Setting "V=..." takes precedence over KBUILD_VERBOSE. @@ -35,14 +35,14 @@ KBUILD_OUTPUT -------------------------------------------------- Specify the output directory when building the kernel. The output directory can also be specificed using "O=...". -Setting "O=..." takes precedence over KBUILD_OUTPUT +Setting "O=..." takes precedence over KBUILD_OUTPUT. ARCH -------------------------------------------------- Set ARCH to the architecture to be built. In most cases the name of the architecture is the same as the directory name found in the arch/ directory. -But some architectures suach as x86 and sparc has aliases. +But some architectures such as x86 and sparc have aliases. x86: i386 for 32 bit, x86_64 for 64 bit sparc: sparc for 32 bit, sparc64 for 64 bit @@ -63,7 +63,7 @@ CF is often used on the command-line like this: INSTALL_PATH -------------------------------------------------- INSTALL_PATH specifies where to place the updated kernel and system map -images. Default is /boot, but you can set it to other values +images. Default is /boot, but you can set it to other values. MODLIB @@ -90,7 +90,7 @@ INSTALL_MOD_STRIP will used as the options to the strip command. INSTALL_FW_PATH -------------------------------------------------- -INSTALL_FW_PATH specify where to install the firmware blobs. +INSTALL_FW_PATH specifies where to install the firmware blobs. The default value is: $(INSTALL_MOD_PATH)/lib/firmware @@ -99,7 +99,7 @@ The value can be overridden in which case the default value is ignored. INSTALL_HDR_PATH -------------------------------------------------- -INSTALL_HDR_PATH specify where to install user space headers when +INSTALL_HDR_PATH specifies where to install user space headers when executing "make headers_*". The default value is: @@ -112,22 +112,23 @@ The value can be overridden in which case the default value is ignored. KBUILD_MODPOST_WARN -------------------------------------------------- -KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined -symbols in the final module linking stage. +KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined +symbols in the final module linking stage. It changes such errors +into warnings. -KBUILD_MODPOST_FINAL +KBUILD_MODPOST_NOFINAL -------------------------------------------------- KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. -This is solely usefull to speed up test compiles. +This is solely useful to speed up test compiles. KBUILD_EXTRA_SYMBOLS -------------------------------------------------- -For modules use symbols from another modules. +For modules that use symbols from other modules. See more details in modules.txt. ALLSOURCE_ARCHS -------------------------------------------------- -For tags/TAGS/cscope targets, you can specify more than one archs -to be included in the databases, separated by blankspace. e.g. +For tags/TAGS/cscope targets, you can specify more than one arch +to be included in the databases, separated by blank space. E.g.: $ make ALLSOURCE_ARCHS="x86 mips arm" tags diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index fb849020aea..d8362cf9909 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -141,6 +141,7 @@ and is between 256 and 4096 characters. It is defined in the file ht -- run only enough ACPI to enable Hyper Threading strict -- Be less tolerant of platforms that are not strictly ACPI specification compliant. + rsdt -- prefer RSDT over (default) XSDT See also Documentation/power/pm.txt, pci=noacpi @@ -151,16 +152,20 @@ and is between 256 and 4096 characters. It is defined in the file default: 0 acpi_sleep= [HW,ACPI] Sleep options - Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, old_ordering } - See Documentation/power/video.txt for s3_bios and s3_mode. + Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, + old_ordering, s4_nonvs } + See Documentation/power/video.txt for information on + s3_bios and s3_mode. s3_beep is for debugging; it makes the PC's speaker beep as soon as the kernel's real-mode entry point is called. s4_nohwsig prevents ACPI hardware signature from being used during resume from hibernation. old_ordering causes the ACPI 1.0 ordering of the _PTS - control method, wrt putting devices into low power - states, to be enforced (the ACPI 2.0 ordering of _PTS is - used by default). + control method, with respect to putting devices into + low power states, to be enforced (the ACPI 2.0 ordering + of _PTS is used by default). + s4_nonvs prevents the kernel from saving/restoring the + ACPI NVS memory during hibernation. acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode Format: { level | edge | high | low } @@ -195,7 +200,7 @@ and is between 256 and 4096 characters. It is defined in the file acpi_skip_timer_override [HW,ACPI] Recognize and ignore IRQ0/pin2 Interrupt Override. For broken nForce2 BIOS resulting in XT-PIC timer. - acpi_use_timer_override [HW,ACPI} + acpi_use_timer_override [HW,ACPI] Use timer override. For some broken Nvidia NF5 boards that require a timer override, but don't have HPET @@ -572,9 +577,6 @@ and is between 256 and 4096 characters. It is defined in the file a memory unit (amount[KMG]). See also Documentation/kdump/kdump.txt for a example. - cs4232= [HW,OSS] - Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq> - cs89x0_dma= [HW,NET] Format: <dma> @@ -727,10 +729,6 @@ and is between 256 and 4096 characters. It is defined in the file Default value is 0. Value can be changed at runtime via /selinux/enforce. - es1371= [HW,OSS] - Format: <spdif>,[<nomix>,[<amplifier>]] - See also header of sound/oss/es1371.c. - ether= [HW,NET] Ethernet cards parameters This option is obsoleted by the "netdev=" option, which has equivalent usage. See its documentation for details. @@ -829,8 +827,8 @@ and is between 256 and 4096 characters. It is defined in the file hlt [BUGS=ARM,SH] - hvc_iucv= [S390] Number of z/VM IUCV Hypervisor console (HVC) - back-ends. Valid parameters: 0..8 + hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) + terminal devices. Valid values: 0..8 i8042.debug [HW] Toggle i8042 debug mode i8042.direct [HW] Put keyboard port into non-translated mode @@ -878,17 +876,19 @@ and is between 256 and 4096 characters. It is defined in the file See Documentation/ide/ide.txt. idle= [X86] - Format: idle=poll or idle=mwait, idle=halt, idle=nomwait - Poll forces a polling idle loop that can slightly improves the performance - of waking up a idle CPU, but will use a lot of power and make the system - run hot. Not recommended. - idle=mwait. On systems which support MONITOR/MWAIT but the kernel chose - to not use it because it doesn't save as much power as a normal idle - loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same - as idle=poll. - idle=halt. Halt is forced to be used for CPU idle. + Format: idle=poll, idle=mwait, idle=halt, idle=nomwait + Poll forces a polling idle loop that can slightly + improve the performance of waking up a idle CPU, but + will use a lot of power and make the system run hot. + Not recommended. + idle=mwait: On systems which support MONITOR/MWAIT but + the kernel chose to not use it because it doesn't save + as much power as a normal idle loop, use the + MONITOR/MWAIT idle loop anyways. Performance should be + the same as idle=poll. + idle=halt: Halt is forced to be used for CPU idle. In such case C2/C3 won't be used again. - idle=nomwait. Disable mwait for CPU C-states + idle=nomwait: Disable mwait for CPU C-states ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem Claim all unknown PCI IDE storage controllers. @@ -1074,8 +1074,8 @@ and is between 256 and 4096 characters. It is defined in the file lapic [X86-32,APIC] Enable the local APIC even if BIOS disabled it. - lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer in - C2 power state. + lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer + in C2 power state. libata.dma= [LIBATA] DMA control libata.dma=0 Disable all PATA and SATA DMA @@ -2303,7 +2303,8 @@ and is between 256 and 4096 characters. It is defined in the file thermal.psv= [HW,ACPI] -1: disable all passive trip points - <degrees C>: override all passive trip points to this value + <degrees C>: override all passive trip points to this + value thermal.tzp= [HW,ACPI] Specify global default ACPI thermal zone polling rate diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 898b4987bb8..41bc99fa188 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1,7 +1,7 @@ ThinkPad ACPI Extras Driver - Version 0.21 - May 29th, 2008 + Version 0.22 + November 23rd, 2008 Borislav Deianov <borislav@users.sf.net> Henrique de Moraes Holschuh <hmh@hmh.eng.br> @@ -16,7 +16,8 @@ supported by the generic Linux ACPI drivers. This driver used to be named ibm-acpi until kernel 2.6.21 and release 0.13-20070314. It used to be in the drivers/acpi tree, but it was moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel -2.6.22, and release 0.14. +2.6.22, and release 0.14. It was moved to drivers/platform/x86 for +kernel 2.6.29 and release 0.22. The driver is named "thinkpad-acpi". In some places, like module names, "thinkpad_acpi" is used because of userspace issues. @@ -1412,6 +1413,24 @@ Sysfs notes: rfkill controller switch "tpacpi_wwan_sw": refer to Documentation/rfkill.txt for details. +EXPERIMENTAL: UWB +----------------- + +This feature is marked EXPERIMENTAL because it has not been extensively +tested and validated in various ThinkPad models yet. The feature may not +work as expected. USE WITH CAUTION! To use this feature, you need to supply +the experimental=1 parameter when loading the module. + +sysfs rfkill class: switch "tpacpi_uwb_sw" + +This feature exports an rfkill controller for the UWB device, if one is +present and enabled in the BIOS. + +Sysfs notes: + + rfkill controller switch "tpacpi_uwb_sw": refer to + Documentation/rfkill.txt for details. + Multiple Commands, Module Parameters ------------------------------------ diff --git a/Documentation/lguest/Makefile b/Documentation/lguest/Makefile index 725eef81cd4..1f4f9e888bd 100644 --- a/Documentation/lguest/Makefile +++ b/Documentation/lguest/Makefile @@ -1,5 +1,5 @@ # This creates the demonstration utility "lguest" which runs a Linux guest. -CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include +CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include -U_FORTIFY_SOURCE LDLIBS:=-lz all: lguest diff --git a/Documentation/mips/AU1xxx_IDE.README b/Documentation/mips/AU1xxx_IDE.README index f54962aea84..8ace35ebdcd 100644 --- a/Documentation/mips/AU1xxx_IDE.README +++ b/Documentation/mips/AU1xxx_IDE.README @@ -52,14 +52,12 @@ Two files are introduced: b) 'drivers/ide/mips/au1xxx-ide.c' contains the functionality of the AU1XXX IDE driver -Four configs variables are introduced: +Following extra configs variables are introduced: CONFIG_BLK_DEV_IDE_AU1XXX_PIO_DBDMA - enable the PIO+DBDMA mode CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA - enable the MWDMA mode CONFIG_BLK_DEV_IDE_AU1XXX_BURSTABLE_ON - set Burstable FIFO in DBDMA controller - CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ - maximum transfer size - per descriptor SUPPORTED IDE MODES @@ -87,7 +85,6 @@ CONFIG_BLK_DEV_IDEDMA_PCI=y CONFIG_IDEDMA_PCI_AUTO=y CONFIG_BLK_DEV_IDE_AU1XXX=y CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA=y -CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ=128 CONFIG_BLK_DEV_IDEDMA=y CONFIG_IDEDMA_AUTO=y @@ -105,7 +102,6 @@ CONFIG_BLK_DEV_IDEDMA_PCI=y CONFIG_IDEDMA_PCI_AUTO=y CONFIG_BLK_DEV_IDE_AU1XXX=y CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA=y -CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ=128 CONFIG_BLK_DEV_IDEDMA=y CONFIG_IDEDMA_AUTO=y diff --git a/Documentation/networking/alias.txt b/Documentation/networking/alias.txt index cd12c2ff518..85046f53fcf 100644 --- a/Documentation/networking/alias.txt +++ b/Documentation/networking/alias.txt @@ -2,13 +2,13 @@ IP-Aliasing: ============ -IP-aliases are additional IP-addresses/masks hooked up to a base -interface by adding a colon and a string when running ifconfig. -This string is usually numeric, but this is not a must. - -IP-Aliases are avail if CONFIG_INET (`standard' IPv4 networking) -is configured in the kernel. +IP-aliases are an obsolete way to manage multiple IP-addresses/masks +per interface. Newer tools such as iproute2 support multiple +address/prefixes per interface, but aliases are still supported +for backwards compatibility. +An alias is formed by adding a colon and a string when running ifconfig. +This string is usually numeric, but this is not a must. o Alias creation. Alias creation is done by 'magic' interface naming: eg. to create a @@ -38,16 +38,3 @@ o Relationship with main device If the base device is shut down the added aliases will be deleted too. - - -Contact -------- -Please finger or e-mail me: - Juan Jose Ciarlante <jjciarla@raiz.uncu.edu.ar> - -Updated by Erik Schoenfelder <schoenfr@gaertner.DE> - -; local variables: -; mode: indented-text -; mode: auto-fill -; end: diff --git a/Documentation/networking/netconsole.txt b/Documentation/networking/netconsole.txt index 3c2f2b32863..8d022073e3e 100644 --- a/Documentation/networking/netconsole.txt +++ b/Documentation/networking/netconsole.txt @@ -51,7 +51,8 @@ Built-in netconsole starts immediately after the TCP stack is initialized and attempts to bring up the supplied dev at the supplied address. -The remote host can run either 'netcat -u -l -p <port>' or syslogd. +The remote host can run either 'netcat -u -l -p <port>', +'nc -l -u <port>' or syslogd. Dynamic reconfiguration: ======================== diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt index 7714f57caad..b565e8279d1 100644 --- a/Documentation/nommu-mmap.txt +++ b/Documentation/nommu-mmap.txt @@ -109,12 +109,18 @@ and it's also much more restricted in the latter case: FURTHER NOTES ON NO-MMU MMAP ============================ - (*) A request for a private mapping of less than a page in size may not return - a page-aligned buffer. This is because the kernel calls kmalloc() to - allocate the buffer, not get_free_page(). + (*) A request for a private mapping of a file may return a buffer that is not + page-aligned. This is because XIP may take place, and the data may not be + paged aligned in the backing store. - (*) A list of all the mappings on the system is visible through /proc/maps in - no-MMU mode. + (*) A request for an anonymous mapping will always be page aligned. If + possible the size of the request should be a power of two otherwise some + of the space may be wasted as the kernel must allocate a power-of-2 + granule but will only discard the excess if appropriately configured as + this has an effect on fragmentation. + + (*) A list of all the private copy and anonymous mappings on the system is + visible through /proc/maps in no-MMU mode. (*) A list of all the mappings in use by a process is visible through /proc/<pid>/maps in no-MMU mode. @@ -242,3 +248,18 @@ PROVIDING SHAREABLE BLOCK DEVICE SUPPORT Provision of shared mappings on block device files is exactly the same as for character devices. If there isn't a real device underneath, then the driver should allocate sufficient contiguous memory to honour any supported mapping. + + +================================= +ADJUSTING PAGE TRIMMING BEHAVIOUR +================================= + +NOMMU mmap automatically rounds up to the nearest power-of-2 number of pages +when performing an allocation. This can have adverse effects on memory +fragmentation, and as such, is left configurable. The default behaviour is to +aggressively trim allocations and discard any excess pages back in to the page +allocator. In order to retain finer-grained control over fragmentation, this +behaviour can either be disabled completely, or bumped up to a higher page +watermark where trimming begins. + +Page trimming behaviour is configurable via the sysctl `vm.nr_trim_pages'. diff --git a/Documentation/powerpc/dts-bindings/4xx/ndfc.txt b/Documentation/powerpc/dts-bindings/4xx/ndfc.txt new file mode 100644 index 00000000000..869f0b5f16e --- /dev/null +++ b/Documentation/powerpc/dts-bindings/4xx/ndfc.txt @@ -0,0 +1,39 @@ +AMCC NDFC (NanD Flash Controller) + +Required properties: +- compatible : "ibm,ndfc". +- reg : should specify chip select and size used for the chip (0x2000). + +Optional properties: +- ccr : NDFC config and control register value (default 0). +- bank-settings : NDFC bank configuration register value (default 0). + +Notes: +- partition(s) - follows the OF MTD standard for partitions + +Example: + +ndfc@1,0 { + compatible = "ibm,ndfc"; + reg = <0x00000001 0x00000000 0x00002000>; + ccr = <0x00001000>; + bank-settings = <0x80002222>; + #address-cells = <1>; + #size-cells = <1>; + + nand { + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + label = "kernel"; + reg = <0x00000000 0x00200000>; + }; + partition@200000 { + label = "root"; + reg = <0x00200000 0x03E00000>; + }; + }; +}; + + diff --git a/Documentation/scheduler/sched-design-CFS.txt b/Documentation/scheduler/sched-design-CFS.txt index 8398ca4ff4e..6f33593e59e 100644 --- a/Documentation/scheduler/sched-design-CFS.txt +++ b/Documentation/scheduler/sched-design-CFS.txt @@ -231,7 +231,7 @@ CPU bandwidth control purposes: This options needs CONFIG_CGROUPS to be defined, and lets the administrator create arbitrary groups of tasks, using the "cgroup" pseudo filesystem. See - Documentation/cgroups.txt for more information about this filesystem. + Documentation/cgroups/cgroups.txt for more information about this filesystem. Only one of these options to group tasks can be chosen and not both. diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 4b7ac21ea9e..0f5d26bea80 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -275,7 +275,8 @@ STAC9200 dell-m25 Dell Inspiron E1505n dell-m26 Dell Inspiron 1501 dell-m27 Dell Inspiron E1705/9400 - gateway Gateway laptops with EAPD control + gateway-m4 Gateway laptops with EAPD control + gateway-m4-2 Gateway laptops with EAPD control panasonic Panasonic CF-74 STAC9205/9254 @@ -302,6 +303,7 @@ STAC9220/9221 macbook-pro Intel Mac Book Pro 2nd generation (eq. type 3) imac-intel Intel iMac (eq. type 2) imac-intel-20 Intel iMac (newer version) (eq. type 3) + ecs202 ECS/PC chips dell-d81 Dell (unknown) dell-d82 Dell (unknown) dell-m81 Dell (unknown) @@ -310,9 +312,13 @@ STAC9220/9221 STAC9202/9250/9251 ================== ref Reference board, base config + m1 Some Gateway MX series laptops (NX560XL) + m1-2 Some Gateway MX series laptops (MX6453) + m2 Some Gateway MX series laptops (M255) m2-2 Some Gateway MX series laptops + m3 Some Gateway MX series laptops + m5 Some Gateway MX series laptops (MP6954) m6 Some Gateway NX series laptops - pa6 Gateway NX860 series STAC9227/9228/9229/927x ======================= @@ -329,6 +335,7 @@ STAC92HD71B* dell-m4-1 Dell desktops dell-m4-2 Dell desktops dell-m4-3 Dell desktops + hp-m4 HP dv laptops STAC92HD73* =========== @@ -337,10 +344,12 @@ STAC92HD73* dell-m6-amic Dell desktops/laptops with analog mics dell-m6-dmic Dell desktops/laptops with digital mics dell-m6 Dell desktops/laptops with both type of mics + dell-eq Dell desktops/laptops STAC92HD83* =========== ref Reference board + mic-ref Reference board with power managment for ports STAC9872 ======== diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index cd05994a49e..3197fc83bc5 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -1,12 +1,13 @@ -Documentation for /proc/sys/vm/* kernel version 2.2.10 +Documentation for /proc/sys/vm/* kernel version 2.6.29 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> + (c) 2008 Peter W. Morreale <pmorreale@novell.com> For general info and legal blurb, please look in README. ============================================================== This file contains the documentation for the sysctl files in -/proc/sys/vm and is valid for Linux kernel version 2.2. +/proc/sys/vm and is valid for Linux kernel version 2.6.29. The files in this directory can be used to tune the operation of the virtual memory (VM) subsystem of the Linux kernel and @@ -16,179 +17,274 @@ Default values and initialization routines for most of these files can be found in mm/swap.c. Currently, these files are in /proc/sys/vm: -- overcommit_memory -- page-cluster -- dirty_ratio + +- block_dump +- dirty_background_bytes - dirty_background_ratio +- dirty_bytes - dirty_expire_centisecs +- dirty_ratio - dirty_writeback_centisecs -- highmem_is_dirtyable (only if CONFIG_HIGHMEM set) +- drop_caches +- hugepages_treat_as_movable +- hugetlb_shm_group +- laptop_mode +- legacy_va_layout +- lowmem_reserve_ratio - max_map_count - min_free_kbytes -- laptop_mode -- block_dump -- drop-caches -- zone_reclaim_mode -- min_unmapped_ratio - min_slab_ratio -- panic_on_oom -- oom_dump_tasks -- oom_kill_allocating_task -- mmap_min_address -- numa_zonelist_order +- min_unmapped_ratio +- mmap_min_addr - nr_hugepages - nr_overcommit_hugepages +- nr_pdflush_threads +- nr_trim_pages (only if CONFIG_MMU=n) +- numa_zonelist_order +- oom_dump_tasks +- oom_kill_allocating_task +- overcommit_memory +- overcommit_ratio +- page-cluster +- panic_on_oom +- percpu_pagelist_fraction +- stat_interval +- swappiness +- vfs_cache_pressure +- zone_reclaim_mode + ============================================================== -dirty_bytes, dirty_ratio, dirty_background_bytes, -dirty_background_ratio, dirty_expire_centisecs, -dirty_writeback_centisecs, highmem_is_dirtyable, -vfs_cache_pressure, laptop_mode, block_dump, swap_token_timeout, -drop-caches, hugepages_treat_as_movable: +block_dump -See Documentation/filesystems/proc.txt +block_dump enables block I/O debugging when set to a nonzero value. More +information on block I/O debugging is in Documentation/laptops/laptop-mode.txt. ============================================================== -overcommit_memory: +dirty_background_bytes -This value contains a flag that enables memory overcommitment. +Contains the amount of dirty memory at which the pdflush background writeback +daemon will start writeback. -When this flag is 0, the kernel attempts to estimate the amount -of free memory left when userspace requests more memory. +If dirty_background_bytes is written, dirty_background_ratio becomes a function +of its value (dirty_background_bytes / the amount of dirtyable system memory). -When this flag is 1, the kernel pretends there is always enough -memory until it actually runs out. +============================================================== -When this flag is 2, the kernel uses a "never overcommit" -policy that attempts to prevent any overcommit of memory. +dirty_background_ratio -This feature can be very useful because there are a lot of -programs that malloc() huge amounts of memory "just-in-case" -and don't use much of it. +Contains, as a percentage of total system memory, the number of pages at which +the pdflush background writeback daemon will start writing out dirty data. -The default value is 0. +============================================================== -See Documentation/vm/overcommit-accounting and -security/commoncap.c::cap_vm_enough_memory() for more information. +dirty_bytes + +Contains the amount of dirty memory at which a process generating disk writes +will itself start writeback. + +If dirty_bytes is written, dirty_ratio becomes a function of its value +(dirty_bytes / the amount of dirtyable system memory). ============================================================== -overcommit_ratio: +dirty_expire_centisecs -When overcommit_memory is set to 2, the committed address -space is not permitted to exceed swap plus this percentage -of physical RAM. See above. +This tunable is used to define when dirty data is old enough to be eligible +for writeout by the pdflush daemons. It is expressed in 100'ths of a second. +Data which has been dirty in-memory for longer than this interval will be +written out next time a pdflush daemon wakes up. + +============================================================== + +dirty_ratio + +Contains, as a percentage of total system memory, the number of pages at which +a process which is generating disk writes will itself start writing out dirty +data. ============================================================== -page-cluster: +dirty_writeback_centisecs -The Linux VM subsystem avoids excessive disk seeks by reading -multiple pages on a page fault. The number of pages it reads -is dependent on the amount of memory in your machine. +The pdflush writeback daemons will periodically wake up and write `old' data +out to disk. This tunable expresses the interval between those wakeups, in +100'ths of a second. -The number of pages the kernel reads in at once is equal to -2 ^ page-cluster. Values above 2 ^ 5 don't make much sense -for swap because we only cluster swap data in 32-page groups. +Setting this to zero disables periodic writeback altogether. ============================================================== -max_map_count: +drop_caches -This file contains the maximum number of memory map areas a process -may have. Memory map areas are used as a side-effect of calling -malloc, directly by mmap and mprotect, and also when loading shared -libraries. +Writing to this will cause the kernel to drop clean caches, dentries and +inodes from memory, causing that memory to become free. -While most applications need less than a thousand maps, certain -programs, particularly malloc debuggers, may consume lots of them, -e.g., up to one or two maps per allocation. +To free pagecache: + echo 1 > /proc/sys/vm/drop_caches +To free dentries and inodes: + echo 2 > /proc/sys/vm/drop_caches +To free pagecache, dentries and inodes: + echo 3 > /proc/sys/vm/drop_caches -The default value is 65536. +As this is a non-destructive operation and dirty objects are not freeable, the +user should run `sync' first. ============================================================== -min_free_kbytes: +hugepages_treat_as_movable -This is used to force the Linux VM to keep a minimum number -of kilobytes free. The VM uses this number to compute a pages_min -value for each lowmem zone in the system. Each lowmem zone gets -a number of reserved free pages based proportionally on its size. +This parameter is only useful when kernelcore= is specified at boot time to +create ZONE_MOVABLE for pages that may be reclaimed or migrated. Huge pages +are not movable so are not normally allocated from ZONE_MOVABLE. A non-zero +value written to hugepages_treat_as_movable allows huge pages to be allocated +from ZONE_MOVABLE. -Some minimal amount of memory is needed to satisfy PF_MEMALLOC -allocations; if you set this to lower than 1024KB, your system will -become subtly broken, and prone to deadlock under high loads. - -Setting this too high will OOM your machine instantly. +Once enabled, the ZONE_MOVABLE is treated as an area of memory the huge +pages pool can easily grow or shrink within. Assuming that applications are +not running that mlock() a lot of memory, it is likely the huge pages pool +can grow to the size of ZONE_MOVABLE by repeatedly entering the desired value +into nr_hugepages and triggering page reclaim. ============================================================== -percpu_pagelist_fraction +hugetlb_shm_group -This is the fraction of pages at most (high mark pcp->high) in each zone that -are allocated for each per cpu page list. The min value for this is 8. It -means that we don't allow more than 1/8th of pages in each zone to be -allocated in any single per_cpu_pagelist. This entry only changes the value -of hot per cpu pagelists. User can specify a number like 100 to allocate -1/100th of each zone to each per cpu page list. +hugetlb_shm_group contains group id that is allowed to create SysV +shared memory segment using hugetlb page. -The batch value of each per cpu pagelist is also updated as a result. It is -set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) +============================================================== -The initial value is zero. Kernel does not use this value at boot time to set -the high water marks for each per cpu page list. +laptop_mode -=============================================================== +laptop_mode is a knob that controls "laptop mode". All the things that are +controlled by this knob are discussed in Documentation/laptops/laptop-mode.txt. -zone_reclaim_mode: +============================================================== -Zone_reclaim_mode allows someone to set more or less aggressive approaches to -reclaim memory when a zone runs out of memory. If it is set to zero then no -zone reclaim occurs. Allocations will be satisfied from other zones / nodes -in the system. +legacy_va_layout -This is value ORed together of +If non-zero, this sysctl disables the new 32-bit mmap mmap layout - the kernel +will use the legacy (2.4) layout for all processes. -1 = Zone reclaim on -2 = Zone reclaim writes dirty pages out -4 = Zone reclaim swaps pages +============================================================== -zone_reclaim_mode is set during bootup to 1 if it is determined that pages -from remote zones will cause a measurable performance reduction. The -page allocator will then reclaim easily reusable pages (those page -cache pages that are currently not used) before allocating off node pages. +lowmem_reserve_ratio + +For some specialised workloads on highmem machines it is dangerous for +the kernel to allow process memory to be allocated from the "lowmem" +zone. This is because that memory could then be pinned via the mlock() +system call, or by unavailability of swapspace. + +And on large highmem machines this lack of reclaimable lowmem memory +can be fatal. + +So the Linux page allocator has a mechanism which prevents allocations +which _could_ use highmem from using too much lowmem. This means that +a certain amount of lowmem is defended from the possibility of being +captured into pinned user memory. + +(The same argument applies to the old 16 megabyte ISA DMA region. This +mechanism will also defend that region from allocations which could use +highmem or lowmem). + +The `lowmem_reserve_ratio' tunable determines how aggressive the kernel is +in defending these lower zones. + +If you have a machine which uses highmem or ISA DMA and your +applications are using mlock(), or if you are running with no swap then +you probably should change the lowmem_reserve_ratio setting. + +The lowmem_reserve_ratio is an array. You can see them by reading this file. +- +% cat /proc/sys/vm/lowmem_reserve_ratio +256 256 32 +- +Note: # of this elements is one fewer than number of zones. Because the highest + zone's value is not necessary for following calculation. + +But, these values are not used directly. The kernel calculates # of protection +pages for each zones from them. These are shown as array of protection pages +in /proc/zoneinfo like followings. (This is an example of x86-64 box). +Each zone has an array of protection pages like this. + +- +Node 0, zone DMA + pages free 1355 + min 3 + low 3 + high 4 + : + : + numa_other 0 + protection: (0, 2004, 2004, 2004) + ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + pagesets + cpu: 0 pcp: 0 + : +- +These protections are added to score to judge whether this zone should be used +for page allocation or should be reclaimed. + +In this example, if normal pages (index=2) are required to this DMA zone and +pages_high is used for watermark, the kernel judges this zone should not be +used because pages_free(1355) is smaller than watermark + protection[2] +(4 + 2004 = 2008). If this protection value is 0, this zone would be used for +normal page requirement. If requirement is DMA zone(index=0), protection[0] +(=0) is used. + +zone[i]'s protection[j] is calculated by following expression. + +(i < j): + zone[i]->protection[j] + = (total sums of present_pages from zone[i+1] to zone[j] on the node) + / lowmem_reserve_ratio[i]; +(i = j): + (should not be protected. = 0; +(i > j): + (not necessary, but looks 0) + +The default values of lowmem_reserve_ratio[i] are + 256 (if zone[i] means DMA or DMA32 zone) + 32 (others). +As above expression, they are reciprocal number of ratio. +256 means 1/256. # of protection pages becomes about "0.39%" of total present +pages of higher zones on the node. + +If you would like to protect more pages, smaller values are effective. +The minimum value is 1 (1/1 -> 100%). -It may be beneficial to switch off zone reclaim if the system is -used for a file server and all of memory should be used for caching files -from disk. In that case the caching effect is more important than -data locality. +============================================================== -Allowing zone reclaim to write out pages stops processes that are -writing large amounts of data from dirtying pages on other nodes. Zone -reclaim will write out dirty pages if a zone fills up and so effectively -throttle the process. This may decrease the performance of a single process -since it cannot use all of system memory to buffer the outgoing writes -anymore but it preserve the memory on other nodes so that the performance -of other processes running on other nodes will not be affected. +max_map_count: -Allowing regular swap effectively restricts allocations to the local -node unless explicitly overridden by memory policies or cpuset -configurations. +This file contains the maximum number of memory map areas a process +may have. Memory map areas are used as a side-effect of calling +malloc, directly by mmap and mprotect, and also when loading shared +libraries. -============================================================= +While most applications need less than a thousand maps, certain +programs, particularly malloc debuggers, may consume lots of them, +e.g., up to one or two maps per allocation. -min_unmapped_ratio: +The default value is 65536. -This is available only on NUMA kernels. +============================================================== -A percentage of the total pages in each zone. Zone reclaim will only -occur if more than this percentage of pages are file backed and unmapped. -This is to insure that a minimal amount of local pages is still available for -file I/O even if the node is overallocated. +min_free_kbytes: -The default is 1 percent. +This is used to force the Linux VM to keep a minimum number +of kilobytes free. The VM uses this number to compute a pages_min +value for each lowmem zone in the system. Each lowmem zone gets +a number of reserved free pages based proportionally on its size. + +Some minimal amount of memory is needed to satisfy PF_MEMALLOC +allocations; if you set this to lower than 1024KB, your system will +become subtly broken, and prone to deadlock under high loads. + +Setting this too high will OOM your machine instantly. ============================================================= @@ -210,82 +306,73 @@ and may not be fast. ============================================================= -panic_on_oom +min_unmapped_ratio: -This enables or disables panic on out-of-memory feature. +This is available only on NUMA kernels. -If this is set to 0, the kernel will kill some rogue process, -called oom_killer. Usually, oom_killer can kill rogue processes and -system will survive. +A percentage of the total pages in each zone. Zone reclaim will only +occur if more than this percentage of pages are file backed and unmapped. +This is to insure that a minimal amount of local pages is still available for +file I/O even if the node is overallocated. -If this is set to 1, the kernel panics when out-of-memory happens. -However, if a process limits using nodes by mempolicy/cpusets, -and those nodes become memory exhaustion status, one process -may be killed by oom-killer. No panic occurs in this case. -Because other nodes' memory may be free. This means system total status -may be not fatal yet. +The default is 1 percent. -If this is set to 2, the kernel panics compulsorily even on the -above-mentioned. +============================================================== -The default value is 0. -1 and 2 are for failover of clustering. Please select either -according to your policy of failover. +mmap_min_addr -============================================================= +This file indicates the amount of address space which a user process will +be restricted from mmaping. Since kernel null dereference bugs could +accidentally operate based on the information in the first couple of pages +of memory userspace processes should not be allowed to write to them. By +default this value is set to 0 and no protections will be enforced by the +security module. Setting this value to something like 64k will allow the +vast majority of applications to work correctly and provide defense in depth +against future potential kernel bugs. -oom_dump_tasks +============================================================== -Enables a system-wide task dump (excluding kernel threads) to be -produced when the kernel performs an OOM-killing and includes such -information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and -name. This is helpful to determine why the OOM killer was invoked -and to identify the rogue task that caused it. +nr_hugepages -If this is set to zero, this information is suppressed. On very -large systems with thousands of tasks it may not be feasible to dump -the memory state information for each one. Such systems should not -be forced to incur a performance penalty in OOM conditions when the -information may not be desired. +Change the minimum size of the hugepage pool. -If this is set to non-zero, this information is shown whenever the -OOM killer actually kills a memory-hogging task. +See Documentation/vm/hugetlbpage.txt -The default value is 0. +============================================================== -============================================================= +nr_overcommit_hugepages -oom_kill_allocating_task +Change the maximum size of the hugepage pool. The maximum is +nr_hugepages + nr_overcommit_hugepages. -This enables or disables killing the OOM-triggering task in -out-of-memory situations. +See Documentation/vm/hugetlbpage.txt -If this is set to zero, the OOM killer will scan through the entire -tasklist and select a task based on heuristics to kill. This normally -selects a rogue memory-hogging task that frees up a large amount of -memory when killed. +============================================================== -If this is set to non-zero, the OOM killer simply kills the task that -triggered the out-of-memory condition. This avoids the expensive -tasklist scan. +nr_pdflush_threads -If panic_on_oom is selected, it takes precedence over whatever value -is used in oom_kill_allocating_task. +The current number of pdflush threads. This value is read-only. +The value changes according to the number of dirty pages in the system. -The default value is 0. +When neccessary, additional pdflush threads are created, one per second, up to +nr_pdflush_threads_max. ============================================================== -mmap_min_addr +nr_trim_pages -This file indicates the amount of address space which a user process will -be restricted from mmaping. Since kernel null dereference bugs could -accidentally operate based on the information in the first couple of pages -of memory userspace processes should not be allowed to write to them. By -default this value is set to 0 and no protections will be enforced by the -security module. Setting this value to something like 64k will allow the -vast majority of applications to work correctly and provide defense in depth -against future potential kernel bugs. +This is available only on NOMMU kernels. + +This value adjusts the excess page trimming behaviour of power-of-2 aligned +NOMMU mmap allocations. + +A value of 0 disables trimming of allocations entirely, while a value of 1 +trims excess pages aggressively. Any value >= 1 acts as the watermark where +trimming of allocations is initiated. + +The default value is 1. + +See Documentation/nommu-mmap.txt for more information. ============================================================== @@ -334,17 +421,199 @@ this is causing problems for your system/application. ============================================================== -nr_hugepages +oom_dump_tasks -Change the minimum size of the hugepage pool. +Enables a system-wide task dump (excluding kernel threads) to be +produced when the kernel performs an OOM-killing and includes such +information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and +name. This is helpful to determine why the OOM killer was invoked +and to identify the rogue task that caused it. -See Documentation/vm/hugetlbpage.txt +If this is set to zero, this information is suppressed. On very +large systems with thousands of tasks it may not be feasible to dump +the memory state information for each one. Such systems should not +be forced to incur a performance penalty in OOM conditions when the +information may not be desired. + +If this is set to non-zero, this information is shown whenever the +OOM killer actually kills a memory-hogging task. + +The default value is 0. ============================================================== -nr_overcommit_hugepages +oom_kill_allocating_task -Change the maximum size of the hugepage pool. The maximum is -nr_hugepages + nr_overcommit_hugepages. +This enables or disables killing the OOM-triggering task in +out-of-memory situations. -See Documentation/vm/hugetlbpage.txt +If this is set to zero, the OOM killer will scan through the entire +tasklist and select a task based on heuristics to kill. This normally +selects a rogue memory-hogging task that frees up a large amount of +memory when killed. + +If this is set to non-zero, the OOM killer simply kills the task that +triggered the out-of-memory condition. This avoids the expensive +tasklist scan. + +If panic_on_oom is selected, it takes precedence over whatever value +is used in oom_kill_allocating_task. + +The default value is 0. + +============================================================== + +overcommit_memory: + +This value contains a flag that enables memory overcommitment. + +When this flag is 0, the kernel attempts to estimate the amount +of free memory left when userspace requests more memory. + +When this flag is 1, the kernel pretends there is always enough +memory until it actually runs out. + +When this flag is 2, the kernel uses a "never overcommit" +policy that attempts to prevent any overcommit of memory. + +This feature can be very useful because there are a lot of +programs that malloc() huge amounts of memory "just-in-case" +and don't use much of it. + +The default value is 0. + +See Documentation/vm/overcommit-accounting and +security/commoncap.c::cap_vm_enough_memory() for more information. + +============================================================== + +overcommit_ratio: + +When overcommit_memory is set to 2, the committed address +space is not permitted to exceed swap plus this percentage +of physical RAM. See above. + +============================================================== + +page-cluster + +page-cluster controls the number of pages which are written to swap in +a single attempt. The swap I/O size. + +It is a logarithmic value - setting it to zero means "1 page", setting +it to 1 means "2 pages", setting it to 2 means "4 pages", etc. + +The default value is three (eight pages at a time). There may be some +small benefits in tuning this to a different value if your workload is +swap-intensive. + +============================================================= + +panic_on_oom + +This enables or disables panic on out-of-memory feature. + +If this is set to 0, the kernel will kill some rogue process, +called oom_killer. Usually, oom_killer can kill rogue processes and +system will survive. + +If this is set to 1, the kernel panics when out-of-memory happens. +However, if a process limits using nodes by mempolicy/cpusets, +and those nodes become memory exhaustion status, one process +may be killed by oom-killer. No panic occurs in this case. +Because other nodes' memory may be free. This means system total status +may be not fatal yet. + +If this is set to 2, the kernel panics compulsorily even on the +above-mentioned. + +The default value is 0. +1 and 2 are for failover of clustering. Please select either +according to your policy of failover. + +============================================================= + +percpu_pagelist_fraction + +This is the fraction of pages at most (high mark pcp->high) in each zone that +are allocated for each per cpu page list. The min value for this is 8. It +means that we don't allow more than 1/8th of pages in each zone to be +allocated in any single per_cpu_pagelist. This entry only changes the value +of hot per cpu pagelists. User can specify a number like 100 to allocate +1/100th of each zone to each per cpu page list. + +The batch value of each per cpu pagelist is also updated as a result. It is +set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) + +The initial value is zero. Kernel does not use this value at boot time to set +the high water marks for each per cpu page list. + +============================================================== + +stat_interval + +The time interval between which vm statistics are updated. The default +is 1 second. + +============================================================== + +swappiness + +This control is used to define how aggressive the kernel will swap +memory pages. Higher values will increase agressiveness, lower values +descrease the amount of swap. + +The default value is 60. + +============================================================== + +vfs_cache_pressure +------------------ + +Controls the tendency of the kernel to reclaim the memory which is used for +caching of directory and inode objects. + +At the default value of vfs_cache_pressure=100 the kernel will attempt to +reclaim dentries and inodes at a "fair" rate with respect to pagecache and +swapcache reclaim. Decreasing vfs_cache_pressure causes the kernel to prefer +to retain dentry and inode caches. Increasing vfs_cache_pressure beyond 100 +causes the kernel to prefer to reclaim dentries and inodes. + +============================================================== + +zone_reclaim_mode: + +Zone_reclaim_mode allows someone to set more or less aggressive approaches to +reclaim memory when a zone runs out of memory. If it is set to zero then no +zone reclaim occurs. Allocations will be satisfied from other zones / nodes +in the system. + +This is value ORed together of + +1 = Zone reclaim on +2 = Zone reclaim writes dirty pages out +4 = Zone reclaim swaps pages + +zone_reclaim_mode is set during bootup to 1 if it is determined that pages +from remote zones will cause a measurable performance reduction. The +page allocator will then reclaim easily reusable pages (those page +cache pages that are currently not used) before allocating off node pages. + +It may be beneficial to switch off zone reclaim if the system is +used for a file server and all of memory should be used for caching files +from disk. In that case the caching effect is more important than +data locality. + +Allowing zone reclaim to write out pages stops processes that are +writing large amounts of data from dirtying pages on other nodes. Zone +reclaim will write out dirty pages if a zone fills up and so effectively +throttle the process. This may decrease the performance of a single process +since it cannot use all of system memory to buffer the outgoing writes +anymore but it preserve the memory on other nodes so that the performance +of other processes running on other nodes will not be affected. + +Allowing regular swap effectively restricts allocations to the local +node unless explicitly overridden by memory policies or cpuset +configurations. + +============ End of Document ================================= diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt index 10a0263ebb3..9e592c718af 100644 --- a/Documentation/sysrq.txt +++ b/Documentation/sysrq.txt @@ -1,6 +1,5 @@ Linux Magic System Request Key Hacks Documentation for sysrq.c -Last update: 2007-AUG-04 * What is the magic SysRq key? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -211,6 +210,24 @@ within a function called by handle_sysrq, you must be aware that you are in a lock (you are also in an interrupt handler, which means don't sleep!), so you must call __handle_sysrq_nolock instead. +* When I hit a SysRq key combination only the header appears on the console? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Sysrq output is subject to the same console loglevel control as all +other console output. This means that if the kernel was booted 'quiet' +as is common on distro kernels the output may not appear on the actual +console, even though it will appear in the dmesg buffer, and be accessible +via the dmesg command and to the consumers of /proc/kmsg. As a specific +exception the header line from the sysrq command is passed to all console +consumers as if the current loglevel was maximum. If only the header +is emitted it is almost certain that the kernel loglevel is too low. +Should you require the output on the console channel then you will need +to temporarily up the console loglevel using alt-sysrq-8 or: + + echo 8 > /proc/sysrq-trigger + +Remember to return the loglevel to normal after triggering the sysrq +command you are interested in. + * I have more questions, who can I ask? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ And I'll answer any questions about the registration system you got, also diff --git a/Documentation/usb/dma.txt b/Documentation/usb/dma.txt index e8b50b7de9d..cfdcd16e3ab 100644 --- a/Documentation/usb/dma.txt +++ b/Documentation/usb/dma.txt @@ -6,8 +6,9 @@ in the kernel usb programming guide (kerneldoc, from the source code). API OVERVIEW The big picture is that USB drivers can continue to ignore most DMA issues, -though they still must provide DMA-ready buffers (see DMA-mapping.txt). -That's how they've worked through the 2.4 (and earlier) kernels. +though they still must provide DMA-ready buffers (see +Documentation/PCI/PCI-DMA-mapping.txt). That's how they've worked through +the 2.4 (and earlier) kernels. OR: they can now be DMA-aware. @@ -62,8 +63,8 @@ and effects like cache-trashing can impose subtle penalties. force a consistent memory access ordering by using memory barriers. It's not using a streaming DMA mapping, so it's good for small transfers on systems where the I/O would otherwise thrash an IOMMU mapping. (See - Documentation/DMA-mapping.txt for definitions of "coherent" and "streaming" - DMA mappings.) + Documentation/PCI/PCI-DMA-mapping.txt for definitions of "coherent" and + "streaming" DMA mappings.) Asking for 1/Nth of a page (as well as asking for N pages) is reasonably space-efficient. @@ -93,7 +94,7 @@ WORKING WITH EXISTING BUFFERS Existing buffers aren't usable for DMA without first being mapped into the DMA address space of the device. However, most buffers passed to your driver can safely be used with such DMA mapping. (See the first section -of DMA-mapping.txt, titled "What memory is DMA-able?") +of Documentation/PCI/PCI-DMA-mapping.txt, titled "What memory is DMA-able?") - When you're using scatterlists, you can map everything at once. On some systems, this kicks in an IOMMU and turns the scatterlists into single diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index fcdc62b3c3d..7b4596ac412 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -44,7 +44,7 @@ Protocol 2.07: (Kernel 2.6.24) Added paravirtualised boot protocol. and KEEP_SEGMENTS flag in load_flags. Protocol 2.08: (Kernel 2.6.26) Added crc32 checksum and ELF format - payload. Introduced payload_offset and payload length + payload. Introduced payload_offset and payload_length fields to aid in locating the payload. Protocol 2.09: (Kernel 2.6.26) Added a field of 64-bit physical |