From 290b20a6d34acc188aec01669c210d731cc0ec15 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue, 14 Nov 2017 21:56:55 +0000
Subject: [PATCH] drm/i915: Add might_sleep() check to wait_for()
Git-commit: 290b20a6d34acc188aec01669c210d731cc0ec15
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900
We should long past the time of trying to use wait_for() from inside
atomic contexts, so add a might_sleep() check to prevent misuse.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114215655.4849-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_drv.h | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -47,14 +47,11 @@
* contexts. Note that it's important that we check the condition again after
* having timed out, since the timeout could be due to preemption or similar and
* we've never had a chance to check the condition before the timeout.
- *
- * TODO: When modesetting has fully transitioned to atomic, the below
- * drm_can_sleep() can be removed and in_atomic()/!in_atomic() asserts
- * added.
*/
#define _wait_for(COND, US, W) ({ \
unsigned long timeout__ = jiffies + usecs_to_jiffies(US) + 1; \
int ret__; \
+ might_sleep(); \
for (;;) { \
bool expired__ = time_after(jiffies, timeout__); \
if (COND) { \
@@ -65,11 +62,7 @@
ret__ = -ETIMEDOUT; \
break; \
} \
- if ((W) && drm_can_sleep()) { \
- usleep_range((W), (W)*2); \
- } else { \
- cpu_relax(); \
- } \
+ usleep_range((W), (W) * 2); \
} \
ret__; \
})