linux-stable/include
Eric W. Biederman 99f8955183 [PATCH] proc: don't lock task_structs indefinitely
Every inode in /proc holds a reference to a struct task_struct.  If a
directory or file is opened and remains open after the the task exits this
pinning continues.  With 8K stacks on a 32bit machine the amount pinned per
file descriptor is about 10K.

Normally I would figure a reasonable per user process limit is about 100
processes.  With 80 processes, with a 1000 file descriptors each I can trigger
the 00M killer on a 32bit kernel, because I have pinned about 800MB of useless
data.

This patch replaces the struct task_struct pointer with a pointer to a struct
task_ref which has a struct task_struct pointer.  The so the pinning of dead
tasks does not happen.

The code now has to contend with the fact that the task may now exit at any
time.  Which is a little but not muh more complicated.

With this change it takes about 1000 processes each opening up 1000 file
descriptors before I can trigger the OOM killer.  Much better.

[mlp@google.com: task_mmu small fixes]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Paul Jackson <pj@sgi.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Albert Cahalan <acahalan@gmail.com>
Signed-off-by: Prasanna Meda <mlp@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:25 -07:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2006-06-23 07:52:36 -07:00
asm-alpha [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-arm [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-arm26 [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-cris
asm-frv [PATCH] frv: clean frv unistd.h 2006-06-23 07:42:55 -07:00
asm-generic [PATCH] introduce WARN_ON_ONCE(cond) 2006-06-25 10:01:11 -07:00
asm-h8300 [PATCH] adjust handle_IRR_event() return type 2006-06-23 07:43:08 -07:00
asm-i386 [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-ia64 [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-m32r [PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use 2006-06-22 15:05:58 -07:00
asm-m68k [PATCH] m68k: convert VME irq code 2006-06-25 10:00:58 -07:00
asm-m68knommu [PATCH] m68knommu: make enable_irq() macro statement 2006-06-25 21:04:24 -07:00
asm-mips [PATCH] N32 sigset and __COMPAT_ENDIAN_SWAP__ 2006-06-25 10:01:15 -07:00
asm-parisc [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-powerpc [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-ppc [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-s390 [PATCH] Define __raw_get_cpu_var and use it 2006-06-25 10:01:01 -07:00
asm-sh [PATCH] random: remove SA_SAMPLE_RANDOM from floppy driver 2006-06-25 10:01:00 -07:00
asm-sh64
asm-sparc [SBUS]: Rewrite and plug into of_device framework. 2006-06-23 23:15:50 -07:00
asm-sparc64 [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-um Merge git://git.infradead.org/hdrcleanup-2.6 2006-06-20 15:10:08 -07:00
asm-v850 [PATCH] adjust handle_IRR_event() return type 2006-06-23 07:43:08 -07:00
asm-x86_64 [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
asm-xtensa [PATCH] xtensa: remove verify_area macros 2006-06-23 07:43:02 -07:00
keys [PATCH] keys: discard the contents of a key on revocation 2006-06-26 09:58:18 -07:00
linux [PATCH] proc: don't lock task_structs indefinitely 2006-06-26 09:58:25 -07:00
math-emu
media V4L/DVB (4205): Merge tda9887 module into tuner. 2006-06-25 02:05:24 -03:00
mtd Merge git://git.infradead.org/hdrcleanup-2.6 2006-06-20 15:10:08 -07:00
net [NET]: fix net-core kernel-doc 2006-06-23 02:07:42 -07:00
pcmcia
rdma IB/uverbs: Don't serialize with ib_uverbs_idr_mutex 2006-06-17 20:44:49 -07:00
rxrpc
scsi Merge branch 'master' into upstream 2006-06-22 22:11:56 -04:00
sound V4L/DVB (4210b): git-dvb: tea575x-tuner build fix 2006-06-25 02:05:25 -03:00
video