From d224985a5e312ab05b624143a3fd9bb91b53e52a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 15 Mar 2018 11:41:39 +0100 Subject: [PATCH] sched/wait, drivers/drm: Convert wait_on_atomic_t() usage to the new wait_var_event() API The old wait_on_atomic_t() is going to get removed, use the more flexible wait_var_event() API instead. Unlike wake_up_atomic_t(), wake_up_var() will issue the wakeup even if the variable is not 0. No change in functionality. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Chris Wilson Cc: Daniel Vetter Cc: David Airlie Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- drivers/gpu/drm/drm_dp_aux_dev.c | 13 +++++++------ drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c | 14 ++++---------- 2 files changed, 11 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/drm_dp_aux_dev.c b/drivers/gpu/drm/drm_dp_aux_dev.c index 053044201e31..0e4f25d63fd2 100644 --- a/drivers/gpu/drm/drm_dp_aux_dev.c +++ b/drivers/gpu/drm/drm_dp_aux_dev.c @@ -177,8 +177,9 @@ static ssize_t auxdev_read_iter(struct kiocb *iocb, struct iov_iter *to) res = pos - iocb->ki_pos; iocb->ki_pos = pos; - atomic_dec(&aux_dev->usecount); - wake_up_atomic_t(&aux_dev->usecount); + if (atomic_dec_and_test(&aux_dev->usecount)) + wake_up_var(&aux_dev->usecount); + return res; } @@ -218,8 +219,9 @@ static ssize_t auxdev_write_iter(struct kiocb *iocb, struct iov_iter *from) res = pos - iocb->ki_pos; iocb->ki_pos = pos; - atomic_dec(&aux_dev->usecount); - wake_up_atomic_t(&aux_dev->usecount); + if (atomic_dec_and_test(&aux_dev->usecount)) + wake_up_var(&aux_dev->usecount); + return res; } @@ -277,8 +279,7 @@ void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux) mutex_unlock(&aux_idr_mutex); atomic_dec(&aux_dev->usecount); - wait_on_atomic_t(&aux_dev->usecount, atomic_t_wait, - TASK_UNINTERRUPTIBLE); + wait_var_event(&aux_dev->usecount, !atomic_read(&aux_dev->usecount)); minor = aux_dev->index; if (aux_dev->dev) diff --git a/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c b/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c index 54fc571b1102..46580026c7fc 100644 --- a/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c @@ -271,18 +271,13 @@ struct igt_wakeup { u32 seqno; }; -static int wait_atomic_timeout(atomic_t *p, unsigned int mode) -{ - return schedule_timeout(10 * HZ) ? 0 : -ETIMEDOUT; -} - static bool wait_for_ready(struct igt_wakeup *w) { DEFINE_WAIT(ready); set_bit(IDLE, &w->flags); if (atomic_dec_and_test(w->done)) - wake_up_atomic_t(w->done); + wake_up_var(w->done); if (test_bit(STOP, &w->flags)) goto out; @@ -299,7 +294,7 @@ static bool wait_for_ready(struct igt_wakeup *w) out: clear_bit(IDLE, &w->flags); if (atomic_dec_and_test(w->set)) - wake_up_atomic_t(w->set); + wake_up_var(w->set); return !test_bit(STOP, &w->flags); } @@ -342,7 +337,7 @@ static void igt_wake_all_sync(atomic_t *ready, atomic_set(ready, 0); wake_up_all(wq); - wait_on_atomic_t(set, atomic_t_wait, TASK_UNINTERRUPTIBLE); + wait_var_event(set, !atomic_read(set)); atomic_set(ready, count); atomic_set(done, count); } @@ -350,7 +345,6 @@ static void igt_wake_all_sync(atomic_t *ready, static int igt_wakeup(void *arg) { I915_RND_STATE(prng); - const int state = TASK_UNINTERRUPTIBLE; struct intel_engine_cs *engine = arg; struct igt_wakeup *waiters; DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); @@ -418,7 +412,7 @@ static int igt_wakeup(void *arg) * that they are ready for the next test. We wait until all * threads are complete and waiting for us (i.e. not a seqno). */ - err = wait_on_atomic_t(&done, wait_atomic_timeout, state); + err = wait_var_event_timeout(&done, !atomic_read(&done), 10 * HZ); if (err) { pr_err("Timed out waiting for %d remaining waiters\n", atomic_read(&done)); -- 2.11.0