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2010-03-08blkdev: fix merge_bvec_fn return value checks v2Dmitry Monakhov
merge_bvec_fn() returns bvec->bv_len on success. So we have to check against this value. But in case of fs_optimization merge we compare with wrong value. This patch must be included in b428cd6da7e6559aca69aa2e3a526037d3f20403 But accidentally i've forgot to add this in the initial patch. To make things straight let's replace all such checks. In fact this makes code easy to understand. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-07seq_file: fix new kernel-doc warningsRandy Dunlap
Fix kernel-doc notation in new seq-file functions and correct spelling. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-07Revert "lib: build list_sort() only if needed"Linus Torvalds
This reverts commit a069c266ae5fdfbf5b4aecf2c672413aa33b2504. It turns ou that not only was it missing a case (XFS) that needed it, but perhaps more importantly, people sometimes want to enable new modules that they hadn't had enabled before, and if such a module uses list_sort(), it can't easily be inserted any more. So rather than add a "select LIST_SORT" to the XFS case, just leave it compiled in. It's not all _that_ big, after all, and the inconvenience isn't worth it. Requested-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Don Mullis <don.mullis@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfsLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs: [LogFS] Change magic number [LogFS] Remove h_version field [LogFS] Check feature flags [LogFS] Only write journal if dirty [LogFS] Fix bdev erases [LogFS] Silence gcc [LogFS] Prevent 64bit divisions in hash_index [LogFS] Plug memory leak on error paths [LogFS] Add MAINTAINERS entry [LogFS] add new flash file system Fixed up trivial conflict in lib/Kconfig, and a semantic conflict in fs/logfs/inode.c introduced by write_inode() being changed to use writeback_control' by commit a9185b41a4f84971b930c519f0c63bd450c4810d ("pass writeback_control to ->write_inode")
2010-03-06Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (21 commits) xfs: return inode fork offset in bulkstat for fsr xfs: Increase the default size of the reserved blocks pool xfs: truncate delalloc extents when IO fails in writeback xfs: check for more work before sleeping in xfssyncd xfs: Fix a build warning in xfs_aops.c xfs: fix locking for inode cache radix tree tag updates xfs: remove xfs_ipin/xfs_iunpin xfs: cleanup xfs_iunpin_wait/xfs_iunpin_nowait xfs: kill xfs_lrw.h xfs: factor common xfs_trans_bjoin code xfs: stop passing opaque handles to xfs_log.c routines xfs: split xfs_bmap_btalloc xfs: fix xfs_fsblock_t tracing xfs: fix inode pincount check in fsync xfs: Non-blocking inode locking in IO completion xfs: implement optimized fdatasync xfs: remove wrapper for the fsync file operation xfs: remove wrappers for read/write file operations xfs: merge xfs_lrw.c into xfs_file.c xfs: fix dquota trace format ...
2010-03-06Merge branch 'for-2.6.34' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.34' of git://linux-nfs.org/~bfields/linux: (22 commits) nfsd4: fix minor memory leak svcrpc: treat uid's as unsigned nfsd: ensure sockets are closed on error Revert "sunrpc: move the close processing after do recvfrom method" Revert "sunrpc: fix peername failed on closed listener" sunrpc: remove unnecessary svc_xprt_put NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN xfs_export_operations.commit_metadata commit_metadata export operation replacing nfsd_sync_dir lockd: don't clear sm_monitored on nsm_reboot_lookup lockd: release reference to nsm_handle in nlm_host_rebooted nfsd: Use vfs_fsync_range() in nfsd_commit NFSD: Create PF_INET6 listener in write_ports SUNRPC: NFS kernel APIs shouldn't return ENOENT for "transport not found" SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt() NFSD: Support AF_INET6 in svc_addsock() function SUNRPC: Use rpc_pton() in ip_map_parse() nfsd: 4.1 has an rfc number nfsd41: Create the recovery entry for the NFSv4.1 client nfsd: use vfs_fsync for non-directories ...
2010-03-06coredump: suppress uid comparison test if core output files are pipesNeil Horman
Modify uid check in do_coredump so as to not apply it in the case of pipes. This just got noticed in testing. The end of do_coredump validates the uid of the inode for the created file against the uid of the crashing process to ensure that no one can pre-create a core file with different ownership and grab the information contained in the core when they shouldn' tbe able to. This causes failures when using pipes for a core dumps if the crashing process is not root, which is the uid of the pipe when it is created. The fix is simple. Since the check for matching uid's isn't relevant for pipes (a process can't create a pipe that the uermodehelper code will open anyway), we can just just skip it in the event ispipe is non-zero Reverts a pipe-affecting change which was accidentally made in : commit c46f739dd39db3b07ab5deb4e3ec81e1c04a91af : Author: Ingo Molnar <mingo@elte.hu> : AuthorDate: Wed Nov 28 13:59:18 2007 +0100 : Commit: Linus Torvalds <torvalds@woody.linux-foundation.org> : CommitDate: Wed Nov 28 10:58:01 2007 -0800 : : vfs: coredumping fix Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06coredump: set ->group_exit_code for other CLONE_VM tasks tooOleg Nesterov
User visible change. do_coredump() kills all threads which share the same ->mm but only the coredumping process gets the proper exit_code. Other tasks which share the same ->mm die "silently" and return status == 0 to parent. This is historical behaviour, not actually a bug. But I think Frank Heckenbach rightly dislikes the current behaviour. Simple test-case: #include <stdio.h> #include <unistd.h> #include <signal.h> #include <sys/wait.h> int main(void) { int stat; if (!fork()) { if (!vfork()) kill(getpid(), SIGQUIT); } wait(&stat); printf("stat=%x\n", stat); return 0; } Before this patch it prints "stat=0" despite the fact the child was killed by SIGQUIT. After this patch the output is "stat=3" which obviously makes more sense. Even with this patch, only the task which originates the coredumping gets "|= 0x80" if the core was actually dumped, but at least the coredumping signal is visible to do_wait/etc. Reported-by: Frank Heckenbach <f.heckenbach@fh-soft.de> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Roland McGrath <roland@redhat.com> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06coredump: pass mm->flags as a coredump parameter for consistencyMasami Hiramatsu
Pass mm->flags as a coredump parameter for consistency. --- 1787 if (mm->core_state || !get_dumpable(mm)) { <- (1) 1788 up_write(&mm->mmap_sem); 1789 put_cred(cred); 1790 goto fail; 1791 } 1792 [...] 1798 if (get_dumpable(mm) == 2) { /* Setuid core dump mode */ <-(2) 1799 flag = O_EXCL; /* Stop rewrite attacks */ 1800 cred->fsuid = 0; /* Dump root private */ 1801 } --- Since dumpable bits are not protected by lock, there is a chance to change these bits between (1) and (2). To solve this issue, this patch copies mm->flags to coredump_params.mm_flags at the beginning of do_coredump() and uses it instead of get_dumpable() while dumping core. This copy is also passed to binfmt->core_dump, since elf*_core_dump() uses dump_filter bits in mm->flags. [akpm@linux-foundation.org: fix merge] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06elf coredump: add extended numbering supportDaisuke HATAYAMA
The current ELF dumper implementation can produce broken corefiles if program headers exceed 65535. This number is determined by the number of vmas which the process have. In particular, some extreme programs may use more than 65535 vmas. (If you google max_map_count, you can find some users facing this problem.) This kind of program never be able to generate correct coredumps. This patch implements ``extended numbering'' that uses sh_info field of the first section header instead of e_phnum field in order to represent upto 4294967295 vmas. This is supported by AMD64-ABI(http://www.x86-64.org/documentation.html) and Solaris(http://docs.sun.com/app/docs/doc/817-1984/). Of course, we are preparing patches for gdb and binutils. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06elf coredump: make offset calculation process and writing process explicitDaisuke HATAYAMA
By the next patch, elf_core_dump() and elf_fdpic_core_dump() will support extended numbering and so will produce the corefiles with section header table in a special case. The problem is the process of writing a file header offset of the section header table into e_shoff field of the ELF header. ELF header is positioned at the beginning of the corefile, while section header at the end. So, we need to take which of the following ways: 1. Seek backward to retry writing operation for ELF header after writing process for a whole part 2. Make offset calculation process and writing process totally sequential The clause 1. is not always possible: one cannot assume that file system supports seek function. Consider the no_llseek case. Therefore, this patch adopts the clause 2. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06elf coredump: replace ELF_CORE_EXTRA_* macros by functionsDaisuke HATAYAMA
elf_core_dump() and elf_fdpic_core_dump() use #ifdef and the corresponding macro for hiding _multiline_ logics in functions. This patch removes #ifdef and replaces ELF_CORE_EXTRA_* by corresponding functions. For architectures not implemeonting ELF_CORE_EXTRA_*, we use weak functions in order to reduce a range of modification. This cleanup is for my next patches, but I think this cleanup itself is worth doing regardless of my firnal purpose. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06coredump: move dump_write() and dump_seek() into a header fileDaisuke HATAYAMA
My next patch will replace ELF_CORE_EXTRA_* macros by functions, putting them into other newly created *.c files. Then, each files will contain dump_write(), where each pair of binfmt_*.c and elfcore.c should be the same. So, this patch moves them into a header file with dump_seek(). Also, the patch deletes confusing DUMP_WRITE macros in each files. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06coredump: unify dump_seek() implementations for each binfmt_*.cDaisuke HATAYAMA
The current ELF dumper can produce broken corefiles if program headers exceed 65535. In particular, the program in 64-bit environment often demands more than 65535 mmaps. If you google max_map_count, then you can find many users facing this problem. Solaris has already dealt with this issue, and other OSes have also adopted the same method as in Solaris. Currently, Sun's document and AMD 64 ABI include the description for the extension, where they call the extension Extended Numbering. See Reference for further information. I believe that linux kernel should adopt the same way as they did, so I've written this patch. I am also preparing for patches of GDB and binutils. How to fix ========== In new dumping process, there are two cases according to weather or not the number of program headers is equal to or more than 65535. - if less than 65535, the produced corefile format is exactly the same as the ordinary one. - if equal to or more than 65535, then e_phnum field is set to newly introduced constant PN_XNUM(0xffff) and the actual number of program headers is set to sh_info field of the section header at index 0. Compatibility Concern ===================== * As already mentioned in Summary, Sun and AMD64 has already adopted this. See Reference. * There are four combinations according to whether kernel and userland tools are respectively modified or not. The next table summarizes shortly for each combination. --------------------------------------------- Original Kernel | Modified Kernel --------------------------------------------- < 65535 | >= 65535 | < 65535 | >= 65535 ------------------------------------------------------------- Original Tools | OK | broken | OK | broken (#) ------------------------------------------------------------- Modified Tools | OK | broken | OK | OK ------------------------------------------------------------- Note that there is no case that `OK' changes to `broken'. (#) Although this case remains broken, O-M behaves better than O-O. That is, while in O-O case e_phnum field would be extremely small due to integer overflow, in O-M case it is guaranteed to be at least 65535 by being set to PN_XNUM(0xFFFF), much closer to the actual correct value than the O-O case. Test Program ============ Here is a test program mkmmaps.c that is useful to produce the corefile with many mmaps. To use this, please take the following steps: $ ulimit -c unlimited $ sysctl vm.max_map_count=70000 # default 65530 is too small $ sysctl fs.file-max=70000 $ mkmmaps 65535 Then, the program will abort and a corefile will be generated. If failed, there are two cases according to the error message displayed. * ``out of memory'' means vm.max_map_count is still smaller * ``too many open files'' means fs.file-max is still smaller So, please change it to a larger value, and then retry it. mkmmaps.c == #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char **argv) { int maps_num; if (argc < 2) { fprintf(stderr, "mkmmaps [number of maps to be created]\n"); exit(1); } if (sscanf(argv[1], "%d", &maps_num) == EOF) { perror("sscanf"); exit(2); } if (maps_num < 0) { fprintf(stderr, "%d is invalid\n", maps_num); exit(3); } for (; maps_num > 0; --maps_num) { if (MAP_FAILED == mmap((void *)NULL, (size_t) 1, PROT_READ, MAP_SHARED | MAP_ANONYMOUS, (int) -1, (off_t) NULL)) { perror("mmap"); exit(4); } } abort(); { char buffer[128]; sprintf(buffer, "wc -l /proc/%u/maps", getpid()); system(buffer); } return 0; } Tested on i386, ia64 and um/sys-i386. Built on sh4 (which covers fs/binfmt_elf_fdpic.c) References ========== - Sun microsystems: Linker and Libraries. Part No: 817-1984-17, September 2008. URL: http://docs.sun.com/app/docs/doc/817-1984 - System V ABI AMD64 Architecture Processor Supplement Draft Version 0.99., May 11, 2009. URL: http://www.x86-64.org/ This patch: There are three different definitions for dump_seek() functions in binfmt_aout.c, binfmt_elf.c and binfmt_elf_fdpic.c, respectively. The only for binfmt_elf.c. My next patch will move dump_seek() into a header file in order to share the same implementations for dump_write() and dump_seek(). As the first step, this patch unify these three definitions for dump_seek() by applying the past commits that have been applied only for binfmt_elf.c. Specifically, the modification made here is part of the following commits: * d025c9db7f31fc0554ce7fb2dfc78d35a77f3487 * 7f14daa19ea36b200d237ad3ac5826ae25360461 This patch does not change a shape of corefiles. Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06proc: warn on non-existing proc entriesAlexey Dobriyan
* warn if creation goes on to non-existent directory * warn if removal goes on from non-existing directory * warn if non-existing proc entry is removed Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06proc: do translation + unlink atomically at remove_proc_entry()Alexey Dobriyan
remove_proc_entry() does lock lookup parent unlock lock unlink proc entry from lists unlock which can be made bit more correct by doing parent translation + unlink without dropping lock. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06fs/compat_ioctl.c: suppress two warningsAndrew Morton
fs/compat_ioctl.c: In function 'do_ioctl_trans': fs/compat_ioctl.c:534: warning: 'karg' may be used uninitialized in this function fs/compat_ioctl.c:533: warning: 'kcmd' may be used uninitialized in this function fs/compat_ioctl.c:656: warning: 'ret' may be used uninitialized in this function Reduces text size by 44 bytes. If someone calls one of these functions with an unexpected argument, the code's buggy as-is. Amerigo Wang <amwang@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06lib: build list_sort() only if neededDon Mullis
Build list_sort() only for configs that need it -- those that don't save ~581 bytes (i386). Signed-off-by: Don Mullis <don.mullis@gmail.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Artem Bityutskiy <dedekind@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06exec: create initial stack independent of PAGE_SIZEMichael Neuling
Currently we create the initial stack based on the PAGE_SIZE. This is unnecessary. This creates this initial stack independent of the PAGE_SIZE. It also bumps up the number of 4k pages allocated from 20 to 32, to align with 64K page systems. Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: Helge Deller <deller@gmx.de> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Americo Wang <xiyou.wangcong@gmail.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06fs: use rlimit helpersJiri Slaby
Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in commit 3e10e716abf3 ("resource: add helpers for fetching rlimits") or ACCESS_ONCE if not applicable. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06mm: change anon_vma linking to fix multi-process server scalability issueRik van Riel
The old anon_vma code can lead to scalability issues with heavily forking workloads. Specifically, each anon_vma will be shared between the parent process and all its child processes. In a workload with 1000 child processes and a VMA with 1000 anonymous pages per process that get COWed, this leads to a system with a million anonymous pages in the same anon_vma, each of which is mapped in just one of the 1000 processes. However, the current rmap code needs to walk them all, leading to O(N) scanning complexity for each page. This can result in systems where one CPU is walking the page tables of 1000 processes in page_referenced_one, while all other CPUs are stuck on the anon_vma lock. This leads to catastrophic failure for a benchmark like AIM7, where the total number of processes can reach in the tens of thousands. Real workloads are still a factor 10 less process intensive than AIM7, but they are catching up. This patch changes the way anon_vmas and VMAs are linked, which allows us to associate multiple anon_vmas with a VMA. At fork time, each child process gets its own anon_vmas, in which its COWed pages will be instantiated. The parents' anon_vma is also linked to the VMA, because non-COWed pages could be present in any of the children. This reduces rmap scanning complexity to O(1) for the pages of the 1000 child processes, with O(N) complexity for at most 1/N pages in the system. This reduces the average scanning cost in heavily forking workloads from O(N) to 2. The only real complexity in this patch stems from the fact that linking a VMA to anon_vmas now involves memory allocations. This means vma_adjust can fail, if it needs to attach a VMA to anon_vma structures. This in turn means error handling needs to be added to the calling functions. A second source of complexity is that, because there can be multiple anon_vmas, the anon_vma linking in vma_adjust can no longer be done under "the" anon_vma lock. To prevent the rmap code from walking up an incomplete VMA, this patch introduces the VM_LOCK_RMAP VMA flag. This bit flag uses the same slot as the NOMMU VM_MAPPED_COPY, with an ifdef in mm.h to make sure it is impossible to compile a kernel that needs both symbolic values for the same bitflag. Some test results: Without the anon_vma changes, when AIM7 hits around 9.7k users (on a test box with 16GB RAM and not quite enough IO), the system ends up running >99% in system time, with every CPU on the same anon_vma lock in the pageout code. With these changes, AIM7 hits the cross-over point around 29.7k users. This happens with ~99% IO wait time, there never seems to be any spike in system time. The anon_vma lock contention appears to be resolved. [akpm@linux-foundation.org: cleanups] Signed-off-by: Rik van Riel <riel@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06vfs: take f_lock on modifying f_mode after open timeWu Fengguang
We'll introduce FMODE_RANDOM which will be runtime modified. So protect all runtime modification to f_mode with f_lock to avoid races. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@kernel.org> [2.6.33.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06mm: count swap usageKAMEZAWA Hiroyuki
A frequent questions from users about memory management is what numbers of swap ents are user for processes. And this information will give some hints to oom-killer. Besides we can count the number of swapents per a process by scanning /proc/<pid>/smaps, this is very slow and not good for usual process information handler which works like 'ps' or 'top'. (ps or top is now enough slow..) This patch adds a counter of swapents to mm_counter and update is at each swap events. Information is exported via /proc/<pid>/status file as [kamezawa@bluextal memory]$ cat /proc/self/status Name: cat State: R (running) Tgid: 2910 Pid: 2910 PPid: 2823 TracerPid: 0 Uid: 500 500 500 500 Gid: 500 500 500 500 FDSize: 256 Groups: 500 VmPeak: 82696 kB VmSize: 82696 kB VmLck: 0 kB VmHWM: 432 kB VmRSS: 432 kB VmData: 172 kB VmStk: 84 kB VmExe: 48 kB VmLib: 1568 kB VmPTE: 40 kB VmSwap: 0 kB <=============== this. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06mm: avoid false sharing of mm_counterKAMEZAWA Hiroyuki
Considering the nature of per mm stats, it's the shared object among threads and can be a cache-miss point in the page fault path. This patch adds per-thread cache for mm_counter. RSS value will be counted into a struct in task_struct and synchronized with mm's one at events. Now, in this patch, the event is the number of calls to handle_mm_fault. Per-thread value is added to mm at each 64 calls. rough estimation with small benchmark on parallel thread (2threads) shows [before] 4.5 cache-miss/faults [after] 4.0 cache-miss/faults Anyway, the most contended object is mmap_sem if the number of threads grows. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06mm: clean up mm_counterKAMEZAWA Hiroyuki
Presently, per-mm statistics counter is defined by macro in sched.h This patch modifies it to - defined in mm.h as inlinf functions - use array instead of macro's name creation. This patch is for reducing patch size in future patch to modify implementation of per-mm counter. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06bitops: rename for_each_bit() to for_each_set_bit()Akinobu Mita
Rename for_each_bit to for_each_set_bit in the kernel source tree. To permit for_each_clear_bit(), should that ever be added. The patch includes a macro to map the old for_each_bit() onto the new for_each_set_bit(). This is a (very) temporary thing to ease the migration. [akpm@linux-foundation.org: add temporary for_each_bit()] Suggested-by: Alexey Dobriyan <adobriyan@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06Fix a dumb typo - use of & instead of &&Al Viro
We managed to lose O_DIRECTORY testing due to a stupid typo in commit 1f36f774b2 ("Switch !O_CREAT case to use of do_last()") Reported-by: Walter Sheets <w41ter@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06[LogFS] Change magic numberJoern Engel
Many changes were made during development that could result in old versions of mklogfs and the kernel code being subtly incompatible. Not being a friend of subtleties, I hereby change the magic number. Any old version of mklogfs is now guaranteed to fail.
2010-03-06[LogFS] Remove h_version fieldJoern Engel
Incompatible change: h_compr is moved up so the padding is all in one chunk.
2010-03-05Merge branch 'nfs-for-2.6.34' of ↵Linus Torvalds
git://git.linux-nfs.org/projects/trondmy/nfs-2.6 * 'nfs-for-2.6.34' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (44 commits) NFS: Remove requirement for inode->i_mutex from nfs_invalidate_mapping NFS: Clean up nfs_sync_mapping NFS: Simplify nfs_wb_page() NFS: Replace __nfs_write_mapping with sync_inode() NFS: Simplify nfs_wb_page_cancel() NFS: Ensure inode is always marked I_DIRTY_DATASYNC, if it has unstable pages NFS: Run COMMIT as an asynchronous RPC call when wbc->for_background is set NFS: Reduce the number of unnecessary COMMIT calls NFS: Add a count of the number of unstable writes carried by an inode NFS: Cleanup - move nfs_write_inode() into fs/nfs/write.c nfs41 fix NFS4ERR_CLID_INUSE for exchange id NFS: Fix an allocation-under-spinlock bug SUNRPC: Handle EINVAL error returns from the TCP connect operation NFSv4.1: Various fixes to the sequence flag error handling nfs4: renewd renew operations should take/put a client reference nfs41: renewd sequence operations should take/put client reference nfs: prevent backlogging of renewd requests nfs: kill renewd before clearing client minor version NFS: Make close(2) asynchronous when closing NFS O_DIRECT files NFS: Improve NFS iostat byte count accuracy for writes ...
2010-03-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: fs/9p: Add hardlink support to .u extension 9P2010.L handshake: .L protocol negotiation 9P2010.L handshake: Remove "dotu" variable 9P2010.L handshake: Add mount option 9P2010.L handshake: Add VFS flags net/9p: Handle mount errors correctly. net/9p: Remove MAX_9P_CHAN limit net/9p: Add multi channel support.
2010-03-05Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits) quota: stop using QUOTA_OK / NO_QUOTA dquot: cleanup dquot initialize routine dquot: move dquot initialization responsibility into the filesystem dquot: cleanup dquot drop routine dquot: move dquot drop responsibility into the filesystem dquot: cleanup dquot transfer routine dquot: move dquot transfer responsibility into the filesystem dquot: cleanup inode allocation / freeing routines dquot: cleanup space allocation / freeing routines ext3: add writepage sanity checks ext3: Truncate allocated blocks if direct IO write fails to update i_size quota: Properly invalidate caches even for filesystems with blocksize < pagesize quota: generalize quota transfer interface quota: sb_quota state flags cleanup jbd: Delay discarding buffers in journal_unmap_buffer ext3: quota_write cross block boundary behaviour quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota quota: split out compat_sys_quotactl support from quota.c quota: split out netlink notification support from quota.c quota: remove invalid optimization from quota_sync_all ... Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c
2010-03-05fs/9p: Add hardlink support to .u extensionAneesh Kumar K.V
For regular file and directories we put the link count in th extension field in a tagged string format. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-03-059P2010.L handshake: Remove "dotu" variableSripathi Kodi
Removes 'dotu' variable and make everything dependent on 'proto_version' field. Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-03-059P2010.L handshake: Add VFS flagsSripathi Kodi
Add 9P2000.u and 9P2010.L protocol flags to V9FS VFS This patch adds 9P2000.u and 9P2010.L protocol flags into V9FS VFS side code and removes the single flag used for 'extended'. Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-03-05Merge branch 'writeback-for-2.6.34' into nfs-for-2.6.34Trond Myklebust
2010-03-05NFS: Remove requirement for inode->i_mutex from nfs_invalidate_mappingTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Clean up nfs_sync_mappingTrond Myklebust
Remove the redundant call to filemap_write_and_wait(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Simplify nfs_wb_page()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Replace __nfs_write_mapping with sync_inode()Trond Myklebust
Now that we have correct COMMIT semantics in writeback_single_inode, we can reduce and simplify nfs_wb_all(). Also replace nfs_wb_nocommit() with a call to filemap_write_and_wait(), which doesn't need to hold the inode->i_mutex. With that done, we can eliminate nfs_write_mapping() altogether. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Simplify nfs_wb_page_cancel()Trond Myklebust
In all cases we should be able to just remove the request and call cancel_dirty_page(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Ensure inode is always marked I_DIRTY_DATASYNC, if it has unstable pagesTrond Myklebust
Since nfs_scan_list() doesn't wait for locked pages, we have a race in which it is possible to end up with an inode that needs to send a COMMIT, but which does not have the I_DIRTY_DATASYNC flag set. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Run COMMIT as an asynchronous RPC call when wbc->for_background is setTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Wu Fengguang <fengguang.wu@intel.com>
2010-03-05NFS: Reduce the number of unnecessary COMMIT callsTrond Myklebust
If the caller is doing a non-blocking flush, and there are still writebacks pending on the wire, we can usually defer the COMMIT call until those writes are done. Also ensure that we honour the wbc->nonblocking flag. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Add a count of the number of unstable writes carried by an inodeTrond Myklebust
In order to know when we should do opportunistic commits of the unstable writes, when the VM is doing a background flush, we add a field to count the number of unstable writes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05NFS: Cleanup - move nfs_write_inode() into fs/nfs/write.cTrond Myklebust
The sole purpose of nfs_write_inode is to commit unstable writes, so move it into fs/nfs/write.c, and make nfs_commit_inode static. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05Merge branch 'write_inode2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'write_inode2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: pass writeback_control to ->write_inode make sure data is on disk before calling ->write_inode
2010-03-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: Switch !O_CREAT case to use of do_last() Get rid of symlink body copying Finish pulling of -ESTALE handling to upper level in do_filp_open() Turn do_link spaghetty into a normal loop Unify exits in O_CREAT handling Kill is_link argument of do_last() Pull handling of LAST_BIND into do_last(), clean up ok: part in do_filp_open() Leave mangled flag only for setting nd.intent.open.flag Get rid of passing mangled flag to do_last() Don't pass mangled open_flag to finish_open() pull more into do_last() bail out with ELOOP earlier in do_link loop pull the common predecessors into do_last() postpone __putname() until after do_last() unroll do_last: loop in do_filp_open() Shift releasing nd->root from do_last() to its caller gut do_filp_open() a bit more (do_last separation) beginning to untangle do_filp_open()
2010-03-05Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (36 commits) ext4: fix up rb_root initializations to use RB_ROOT ext4: Code cleanup for EXT4_IOC_MOVE_EXT ioctl ext4: Fix the NULL reference in double_down_write_data_sem() ext4: Fix insertion point of extent in mext_insert_across_blocks() ext4: consolidate in_range() definitions ext4: cleanup to use ext4_grp_offs_to_block() ext4: cleanup to use ext4_group_first_block_no() ext4: Release page references acquired in ext4_da_block_invalidatepages ext4: Fix ext4_quota_write cross block boundary behaviour ext4: Convert BUG_ON checks to use ext4_error() instead ext4: Use direct_IO_no_locking in ext4 dio read ext4: use ext4_get_block_write in buffer write ext4: mechanical rename some of the direct I/O get_block's identifiers ext4: make "offset" consistent in ext4_check_dir_entry() ext4: Handle non empty on-disk orphan link ext4: explicitly remove inode from orphan list after failed direct io ext4: fix error handling in migrate ext4: deprecate obsoleted mount options ext4: Fix fencepost error in chosing choosing group vs file preallocation. jbd2: clean up an assertion in jbd2_journal_commit_transaction() ...
2010-03-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linusLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus: Squashfs: get rid of obsolete definition in header file Squashfs: get rid of obsolete variable in struct squashfs_sb_info Squashfs: add decompressor entries for lzma and lzo Squashfs: add a decompressor framework Squashfs: factor out remaining zlib dependencies into separate wrapper file Squashfs: move zlib decompression wrapper code into a separate file