drm/i915: Serialise resets with wedging

Prevent concurrent set-wedge with ongoing resets (and vice versa) by
taking the same wedge_mutex around both operations.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190208153708.20023-6-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2019-02-08 15:37:07 +00:00
parent 15cbf007e4
commit 72eb16df01

View file

@ -794,17 +794,14 @@ static void nop_submit_request(struct i915_request *request)
intel_engine_queue_breadcrumbs(engine);
}
void i915_gem_set_wedged(struct drm_i915_private *i915)
static void __i915_gem_set_wedged(struct drm_i915_private *i915)
{
struct i915_gpu_error *error = &i915->gpu_error;
struct intel_engine_cs *engine;
enum intel_engine_id id;
mutex_lock(&error->wedge_mutex);
if (test_bit(I915_WEDGED, &error->flags)) {
mutex_unlock(&error->wedge_mutex);
if (test_bit(I915_WEDGED, &error->flags))
return;
}
if (GEM_SHOW_DEBUG() && !intel_engines_are_idle(i915)) {
struct drm_printer p = drm_debug_printer(__func__);
@ -853,12 +850,18 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
set_bit(I915_WEDGED, &error->flags);
GEM_TRACE("end\n");
mutex_unlock(&error->wedge_mutex);
wake_up_all(&error->reset_queue);
}
bool i915_gem_unset_wedged(struct drm_i915_private *i915)
void i915_gem_set_wedged(struct drm_i915_private *i915)
{
struct i915_gpu_error *error = &i915->gpu_error;
mutex_lock(&error->wedge_mutex);
__i915_gem_set_wedged(i915);
mutex_unlock(&error->wedge_mutex);
}
static bool __i915_gem_unset_wedged(struct drm_i915_private *i915)
{
struct i915_gpu_error *error = &i915->gpu_error;
struct i915_timeline *tl;
@ -869,8 +872,6 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
if (!i915->gt.scratch) /* Never full initialised, recovery impossible */
return false;
mutex_lock(&error->wedge_mutex);
GEM_TRACE("start\n");
/*
@ -921,11 +922,21 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
smp_mb__before_atomic(); /* complete takeover before enabling execbuf */
clear_bit(I915_WEDGED, &i915->gpu_error.flags);
mutex_unlock(&i915->gpu_error.wedge_mutex);
return true;
}
bool i915_gem_unset_wedged(struct drm_i915_private *i915)
{
struct i915_gpu_error *error = &i915->gpu_error;
bool result;
mutex_lock(&error->wedge_mutex);
result = __i915_gem_unset_wedged(i915);
mutex_unlock(&error->wedge_mutex);
return result;
}
static int do_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
{
int err, i;
@ -975,7 +986,7 @@ void i915_reset(struct drm_i915_private *i915,
GEM_BUG_ON(!test_bit(I915_RESET_BACKOFF, &error->flags));
/* Clear any previous failed attempts at recovery. Time to try again. */
if (!i915_gem_unset_wedged(i915))
if (!__i915_gem_unset_wedged(i915))
return;
if (reason)
@ -1037,7 +1048,7 @@ taint:
*/
add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
error:
i915_gem_set_wedged(i915);
__i915_gem_set_wedged(i915);
goto finish;
}
@ -1129,7 +1140,9 @@ static void i915_reset_device(struct drm_i915_private *i915,
i915_wedge_on_timeout(&w, i915, 5 * HZ) {
intel_prepare_reset(i915);
mutex_lock(&error->wedge_mutex);
i915_reset(i915, engine_mask, reason);
mutex_unlock(&error->wedge_mutex);
intel_finish_reset(i915);
}
@ -1197,6 +1210,7 @@ void i915_handle_error(struct drm_i915_private *i915,
unsigned long flags,
const char *fmt, ...)
{
struct i915_gpu_error *error = &i915->gpu_error;
struct intel_engine_cs *engine;
intel_wakeref_t wakeref;
unsigned int tmp;
@ -1233,20 +1247,19 @@ void i915_handle_error(struct drm_i915_private *i915,
* Try engine reset when available. We fall back to full reset if
* single reset fails.
*/
if (intel_has_reset_engine(i915) &&
!i915_terminally_wedged(&i915->gpu_error)) {
if (intel_has_reset_engine(i915) && !i915_terminally_wedged(error)) {
for_each_engine_masked(engine, i915, engine_mask, tmp) {
BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
if (test_and_set_bit(I915_RESET_ENGINE + engine->id,
&i915->gpu_error.flags))
&error->flags))
continue;
if (i915_reset_engine(engine, msg) == 0)
engine_mask &= ~intel_engine_flag(engine);
clear_bit(I915_RESET_ENGINE + engine->id,
&i915->gpu_error.flags);
wake_up_bit(&i915->gpu_error.flags,
&error->flags);
wake_up_bit(&error->flags,
I915_RESET_ENGINE + engine->id);
}
}
@ -1255,10 +1268,9 @@ void i915_handle_error(struct drm_i915_private *i915,
goto out;
/* Full reset needs the mutex, stop any other user trying to do so. */
if (test_and_set_bit(I915_RESET_BACKOFF, &i915->gpu_error.flags)) {
wait_event(i915->gpu_error.reset_queue,
!test_bit(I915_RESET_BACKOFF,
&i915->gpu_error.flags));
if (test_and_set_bit(I915_RESET_BACKOFF, &error->flags)) {
wait_event(error->reset_queue,
!test_bit(I915_RESET_BACKOFF, &error->flags));
goto out; /* piggy-back on the other reset */
}
@ -1268,8 +1280,8 @@ void i915_handle_error(struct drm_i915_private *i915,
/* Prevent any other reset-engine attempt. */
for_each_engine(engine, i915, tmp) {
while (test_and_set_bit(I915_RESET_ENGINE + engine->id,
&i915->gpu_error.flags))
wait_on_bit(&i915->gpu_error.flags,
&error->flags))
wait_on_bit(&error->flags,
I915_RESET_ENGINE + engine->id,
TASK_UNINTERRUPTIBLE);
}
@ -1278,11 +1290,11 @@ void i915_handle_error(struct drm_i915_private *i915,
for_each_engine(engine, i915, tmp) {
clear_bit(I915_RESET_ENGINE + engine->id,
&i915->gpu_error.flags);
&error->flags);
}
clear_bit(I915_RESET_BACKOFF, &i915->gpu_error.flags);
wake_up_all(&i915->gpu_error.reset_queue);
clear_bit(I915_RESET_BACKOFF, &error->flags);
wake_up_all(&error->reset_queue);
out:
intel_runtime_pm_put(i915, wakeref);