]> git.baikalelectronics.ru Git - kernel.git/commit
proc: faster /proc/$PID lookup
authorAlexey Dobriyan <adobriyan@gmail.com>
Fri, 8 Aug 2014 21:21:27 +0000 (14:21 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 8 Aug 2014 22:57:22 +0000 (15:57 -0700)
commitf9170581385b9052c02d0378a9a6899cf47f0435
treef12db91b65fa3ea85bad2610aab8dfa3d8f4dfc8
parent836c998b82d2f30c97b1d60bcf47001074e235bc
proc: faster /proc/$PID lookup

Currently lookup for /proc/$PID first goes through spinlock and whole list
of misc /proc entries only to confirm that, yes, /proc/42 can not possibly
match random proc entry.

List is is several dozens entries long (52 entries on my setup).

None of this is necessary.

Try to convert dentry name to integer first.
If it works, it must be /proc/$PID.
If it doesn't, it must be random proc entry.

Based on patch from Al Viro.

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>
fs/proc/base.c
fs/proc/root.c