linux-stable/include
Kent Overstreet 774a08b354 wait: add wait_event_hrtimeout()
Analagous to wait_event_timeout() and friends, this adds
wait_event_hrtimeout() and wait_event_interruptible_hrtimeout().

Note that unlike the versions that use regular timers, these don't
return the amount of time remaining when they return - instead, they
return 0 or -ETIME if they timed out.  because I was uncomfortable with
the semantics of doing it the other way (that I could get it right,
anyways).

If the timer expires, there's no real guarantee that expire_time -
current_time would be <= 0 - due to timer slack certainly, and I'm not
sure I want to know the implications of the different clock bases in
hrtimers.

If the timer does expire and the code calculates that the time remaining
is nonnegative, that could be even worse if the calling code then reuses
that timeout.  Probably safer to just return 0 then, but I could imagine
weird bugs or at least unintended behaviour arising from that too.

I came to the conclusion that if other users end up actually needing the
amount of time remaining, the sanest thing to do would be to create a
version that uses absolute timeouts instead of relative.

[akpm@linux-foundation.org: fix description of `timeout' arg]
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 18:38:28 -07:00
..
acpi Merge branch 'acpi-assorted' 2013-04-28 01:54:08 +02:00
asm-generic Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-05-05 13:23:27 -07:00
clocksource
crypto crypto: sha512 - Expose generic sha512 routine to be callable from other modules 2013-04-25 21:00:57 +08:00
drm Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-05-02 19:40:34 -07:00
dt-bindings
keys
linux wait: add wait_event_hrtimeout() 2013-05-07 18:38:28 -07:00
math-emu
media Merge branch 'topic/omap3isp' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2013-05-01 09:57:04 -07:00
memory
misc
net net: frag, fix race conditions in LRU list maintenance 2013-05-06 11:06:51 -04:00
pcmcia
ras
rdma
rxrpc
scsi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
sound sound updates for v3.10-rc1 2013-05-03 09:10:23 -07:00
target iscsi-target: Add iscsit_transport API template 2013-04-25 01:05:26 -07:00
trace Merge tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2013-05-05 14:47:31 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-05-06 15:51:10 -07:00
video ARM: arm-soc driver changes for 3.10 2013-05-04 12:31:18 -07:00
xen Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
Kbuild UAPI: remove empty Kbuild files 2013-04-30 17:04:09 -07:00