linux/include
Nick Piggin c32ccd87bf [PATCH] inotify: lock avoidance with parent watch status in dentry
Previous inotify work avoidance is good when inotify is completely unused,
but it breaks down if even a single watch is in place anywhere in the
system.  Robin Holt notices that udev is one such culprit - it slows down a
512-thread application on a 512 CPU system from 6 seconds to 22 minutes.

Solve this by adding a flag in the dentry that tells inotify whether or not
its parent inode has a watch on it.  Event queueing to parent will skip
taking locks if this flag is cleared.  Setting and clearing of this flag on
all child dentries versus event delivery: this is no in terms of race
cases, and that was shown to be equivalent to always performing the check.

The essential behaviour is that activity occuring _after_ a watch has been
added and _before_ it has been removed, will generate events.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:53 -08:00
..
acpi [PATCH] s/;;/;/g 2006-03-24 07:33:24 -08:00
asm-alpha
asm-arm [PATCH] AT91RM9200 Ethernet driver 2006-03-24 12:10:55 -05:00
asm-arm26
asm-cris [PATCH] kill include/linux/platform.h, default_idle() cleanup 2006-03-24 07:33:21 -08:00
asm-frv
asm-generic
asm-h8300
asm-i386 [PATCH] kill include/linux/platform.h, default_idle() cleanup 2006-03-24 07:33:21 -08:00
asm-ia64 [PATCH] abstract type/size specification for assembly 2006-03-24 07:33:25 -08:00
asm-m32r
asm-m68k
asm-m68knommu
asm-mips [PATCH] abstract type/size specification for assembly 2006-03-24 07:33:25 -08:00
asm-parisc
asm-powerpc
asm-ppc
asm-s390
asm-sh
asm-sh64
asm-sparc
asm-sparc64
asm-um
asm-v850 [PATCH] abstract type/size specification for assembly 2006-03-24 07:33:25 -08:00
asm-x86_64
asm-xtensa
keys
linux [PATCH] inotify: lock avoidance with parent watch status in dentry 2006-03-25 08:22:53 -08:00
math-emu
media
mtd
net
pcmcia
rdma
rxrpc
scsi
sound [PATCH] sound: remove PC98-specific OPL3_HW_OPL3_PC98 2006-03-24 07:33:26 -08:00
video [PATCH] Remove MODULE_PARM 2006-03-25 08:22:52 -08:00