linux/Documentation/networking, branch v3.4

tcp: change tcp_adv_win_scale and tcp_rmem[2]

2012-05-03T01:08:58Z

tcp_adv_win_scale default value is 2, meaning we expect a good citizen skb to have skb->len / skb->truesize ratio of 75% (3/4) In 2.6 kernels we (mis)accounted for typical MSS=1460 frame : 1536 + 64 + 256 = 1856 'estimated truesize', and 1856 * 3/4 = 1392. So these skbs were considered as not bloated. With recent truesize fixes, a typical MSS=1460 frame truesize is now the more precise : 2048 + 256 = 2304. But 2304 * 3/4 = 1728. So these skb are not good citizen anymore, because 1460 < 1728 (GRO can escape this problem because it build skbs with a too low truesize.) This also means tcp advertises a too optimistic window for a given allocated rcvspace : When receiving frames, sk_rmem_alloc can hit sk_rcvbuf limit and we call tcp_prune_queue()/tcp_collapse() too often, especially when application is slow to drain its receive queue or in case of losses (netperf is fast, scp is slow). This is a major latency source. We should adjust the len/truesize ratio to 50% instead of 75% This patch : 1) changes tcp_adv_win_scale default to 1 instead of 2 2) increase tcp_rmem[2] limit from 4MB to 6MB to take into account better truesize tracking and to allow autotuning tcp receive window to reach same value than before. Note that same amount of kernel memory is consumed compared to 2.6 kernels. Signed-off-by: Eric Dumazet Cc: Neal Cardwell Cc: Tom Herbert Cc: Yuchung Cheng Acked-by: Neal Cardwell Signed-off-by: David S. Miller

doc, net: Update ndo_start_xmit return type and values

2012-04-06T06:43:13Z

Commit dc1f8bf68b311b1537cb65893430b6796118498a ('netdev: change transmit to limited range type') changed the required return type and 9a1654ba0b50402a6bd03c7b0fe9b0200a5ea7b1 ('net: Optimize hard_start_xmit() return checking') changed the valid numerical return values. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

doc, net: Remove instruction to set net_device::trans_start

2012-04-06T06:43:13Z

Commit 08baf561083bc27a953aa087dd8a664bb2b88e8e ('net: txq_trans_update() helper') made it unnecessary for most drivers to set net_device::trans_start (or netdev_queue::trans_start). Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

doc, net: Update netdev operation names

2012-04-06T06:43:12Z

Commits d314774cf2cd5dfeb39a00d37deee65d4c627927 ('netdev: network device operations infrastructure') and 008298231abbeb91bc7be9e8b078607b816d1a4a ('netdev: add more functions to netdevice ops') moved and renamed net device operation pointers. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

doc, net: Update documentation of synchronisation for TX multiqueue

2012-04-06T06:43:12Z

Commits e308a5d806c852f56590ffdd3834d0df0cbed8d7 ('netdev: Add netdev->addr_list_lock protection.') and e8a0464cc950972824e2e128028ae3db666ec1ed ('netdev: Allocate multiple queues for TX.') introduced more fine-grained locks. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

doc, net: Remove obsolete reference to dev->poll

2012-04-06T06:43:12Z

Commit bea3348eef27e6044b6161fd04c3152215f96411 ('[NET]: Make NAPI polling independent of struct net_device objects.') removed the automatic disabling of NAPI polling by dev_close(), and drivers must now do this themselves. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

TCP: update ip_local_port_range documentation

2012-04-03T21:38:55Z

The explanation of ip_local_port_range in Documentation/networking/ip-sysctl.txt contains several factual errors: - The default value of ip_local_port_range does not depend on the amount of memory available in the system. - tcp_tw_recycle is not enabled by default. - 1024-4999 is not the default value. - Etc. Clean up the mess. Signed-off-by: Fernando Luis Vazquez Cao Signed-off-by: David S. Miller

Documentation: replace install commands with softdeps

2012-03-30T23:03:15Z

Install commands should not be used to specify soft dependencies among modules. When loading modules it's much better to have a softdep that modprobe knows what's being done than having to fork/exec another instance of modprobe to load the other module. By using a softdep user has also an option to remove the dependencies when removing the module (and if its refcount dropped to 0) Signed-off-by: Lucas De Marchi Signed-off-by: Linus Torvalds

Documentation: remove references to /etc/modprobe.conf

2012-03-30T23:03:15Z

Usage of /etc/modprobe.conf file was deprecated by module-init-tools and is no longer parsed by new kmod tool. References to this file are replaced in Documentation, comments and Kconfig according to the context. There are also some references to the old /etc/modules.conf from 2.4 kernels that are being removed. Signed-off-by: Lucas De Marchi Acked-by: Takashi Iwai Acked-by: Mauro Carvalho Chehab Signed-off-by: Randy Dunlap Signed-off-by: Linus Torvalds

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2012-03-21T20:25:04Z

Pull security subsystem updates for 3.4 from James Morris: "The main addition here is the new Yama security module from Kees Cook, which was discussed at the Linux Security Summit last year. Its purpose is to collect miscellaneous DAC security enhancements in one place. This also marks a departure in policy for LSM modules, which were previously limited to being standalone access control systems. Chromium OS is using Yama, and I believe there are plans for Ubuntu, at least. This patchset also includes maintenance updates for AppArmor, TOMOYO and others." Fix trivial conflict in due to the jumo_label->static_key rename. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits) AppArmor: Fix location of const qualifier on generated string tables TOMOYO: Return error if fails to delete a domain AppArmor: add const qualifiers to string arrays AppArmor: Add ability to load extended policy TOMOYO: Return appropriate value to poll(). AppArmor: Move path failure information into aa_get_name and rename AppArmor: Update dfa matching routines. AppArmor: Minor cleanup of d_namespace_path to consolidate error handling AppArmor: Retrieve the dentry_path for error reporting when path lookup fails AppArmor: Add const qualifiers to generated string tables AppArmor: Fix oops in policy unpack auditing AppArmor: Fix error returned when a path lookup is disconnected KEYS: testing wrong bit for KEY_FLAG_REVOKED TOMOYO: Fix mount flags checking order. security: fix ima kconfig warning AppArmor: Fix the error case for chroot relative path name lookup AppArmor: fix mapping of META_READ to audit and quiet flags AppArmor: Fix underflow in xindex calculation AppArmor: Fix dropping of allowed operations that are force audited AppArmor: Add mising end of structure test to caps unpacking ...