[tip: irq/core] drm/i915: Use tasklet_unlock_spin_wait() in __tasklet_disable_sync_once()

[tip-bot2 for Sebastian Andrzej Siewior]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     6e457914935a3161eeb74e319abf9fd511aa1e4d
Gitweb:        https://git.kernel.org/tip/6e457914935a3161eeb74e319abf9fd511aa1e4d
Author:        Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
AuthorDate:    Tue, 23 Mar 2021 10:22:21 +01:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 25 Mar 2021 18:21:03 +01:00

drm/i915: Use tasklet_unlock_spin_wait() in __tasklet_disable_sync_once()

The i915 driver has its own tasklet interface which was overseen in the
tasklet rework. __tasklet_disable_sync_once() is a wrapper around
tasklet_unlock_wait(). tasklet_unlock_wait() might sleep, but the i915
wrappers invokes it from non-preemtible contexts with bottom halves disabled.

Use tasklet_unlock_spin_wait() instead which can be invoked from
non-preemptible contexts.

Fixes: da044747401fc ("tasklets: Replace spin wait in tasklet_unlock_wait()")
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210323092221.awq7g5b2muzypjw3@flow
---
 drivers/gpu/drm/i915/i915_gem.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h
index e622aee..440c35f 100644
--- a/drivers/gpu/drm/i915/i915_gem.h
+++ b/drivers/gpu/drm/i915/i915_gem.h
@@ -105,7 +105,7 @@ static inline bool tasklet_is_locked(const struct tasklet_struct *t)
 static inline void __tasklet_disable_sync_once(struct tasklet_struct *t)
 {
 	if (!atomic_fetch_inc(&t->count))
-		tasklet_unlock_wait(t);
+		tasklet_unlock_spin_wait(t);
 }
 
 static inline bool __tasklet_is_enabled(const struct tasklet_struct *t)