]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
Use ERESTART_RESTARTBLOCK if poll() is interrupted by a signal
authorChris Wright <chrisw@sous-sol.org>
Wed, 17 Oct 2007 06:27:18 +0000 (23:27 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Wed, 17 Oct 2007 15:42:53 +0000 (08:42 -0700)
commit3075d9da0b4ccc88959db30de80ebd11d2dde175
tree7dbdcd9b5eae671864eac060ee3138a8c862c0ea
parent7e341fa1f8ed25385e2321d7e5a49ce6aea2d702
Use ERESTART_RESTARTBLOCK if poll() is interrupted by a signal

Lomesh reported poll returning EINTR during suspend/resume cycle.  This is
caused by the STOP/CONT cycle that the freezer uses, generating a pending
signal for what in effect is an ignored signal.  In general poll is a
little eager in returning EINTR, when it could try not bother userspace and
simply restart the syscall.  Both select and ppoll do use ERESTARTNOHAND to
restart the syscall.  Oleg points out that simply using ERESTARTNOHAND will
cause poll to restart with original timeout value.  which could ultimately
lead to process never returning to userspace.  Instead use
ERESTART_RESTARTBLOCK, and restart poll with updated timeout value.
Inspired by Manfred's use ERESTARTNOHAND in poll patch.

[bunk@kernel.org: do_restart_poll() can become static]
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Agarwal, Lomesh" <lomesh.agarwal@intel.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/select.c