Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

From: Hugo Lefeuvre
Date: Fri Jan 18 2019 - 02:56:42 EST

Hi Greg,

> > introduce wait_event_freezable_hrtimeout, an interruptible and freezable
> > version of wait_event_hrtimeout.
> >
> > simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using this
> > newly added helper and remove useless includes.
> >
> > Signed-off-by: Hugo Lefeuvre <hle@xxxxxxxxxx>
> > ---
> > drivers/staging/android/vsoc.c | 69 +++++-----------------------------
> > include/linux/wait.h | 25 ++++++++++--
> code in drivers/staging/ should be self-contained, and not, if at all
> possible, ever force additional changes on "core" kernel code.
> Are you sure that the vsoc code can't use one of the current wait
> macros?

As far as I know there is no macro implementing freezable wait with high
resolution timeout.

> Why is it so special and unique that no one else in the kernel
> has ever needed this before it came along?

many wait_event_X() (_exclusive, _interruptible, _timeout) functions have a
freezable counterpart. wait_event_hrtimeout() doesn't, probably because it
is relatively new (and seemingly quite unused).

If there is a wait_event_hrtimeout() function, it makes sense to me to have

Hugo Lefeuvre (hle) |
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