Message ID | 1480601214-26583-4-git-send-email-nhaehnle@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Thu, Dec 01, 2016 at 03:06:46PM +0100, Nicolai Hähnle wrote: > From: Nicolai Hähnle <Nicolai.Haehnle@amd.com> > > The function will be re-used in subsequent patches. > > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Maarten Lankhorst <dev@mblankhorst.nl> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: Chris Wilson <chris@chris-wilson.co.uk> > Cc: dri-devel@lists.freedesktop.org > Signed-off-by: Nicolai Hähnle <Nicolai.Haehnle@amd.com> > --- > kernel/locking/mutex.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c > index 0afa998..200629a 100644 > --- a/kernel/locking/mutex.c > +++ b/kernel/locking/mutex.c > @@ -277,6 +277,13 @@ static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww, > ww_ctx->acquired++; > } > > +static inline bool __sched > +__ww_mutex_stamp_after(struct ww_acquire_ctx *a, struct ww_acquire_ctx *b) Should it be ww_mutex_stamp or ww_acquire_stamp / ww_ctx_stamp? Nothing else operates on the ww_acquire_ctx without a ww_mutex so it might look a bit odd if it didn't use ww_mutex. Patch only does what it says on tin, so Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> -Chris
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 0afa998..200629a 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -277,6 +277,13 @@ static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww, ww_ctx->acquired++; } +static inline bool __sched +__ww_mutex_stamp_after(struct ww_acquire_ctx *a, struct ww_acquire_ctx *b) +{ + return a->stamp - b->stamp <= LONG_MAX && + (a->stamp != b->stamp || a > b); +} + /* * After acquiring lock with fastpath or when we lost out in contested * slowpath, set ctx and wake up any waiters so they can recheck. @@ -610,8 +617,7 @@ __ww_mutex_lock_check_stamp(struct mutex *lock, struct ww_acquire_ctx *ctx) if (!hold_ctx) return 0; - if (ctx->stamp - hold_ctx->stamp <= LONG_MAX && - (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) { + if (__ww_mutex_stamp_after(ctx, hold_ctx)) { #ifdef CONFIG_DEBUG_MUTEXES DEBUG_LOCKS_WARN_ON(ctx->contending_lock); ctx->contending_lock = ww;