| Message ID | 20171114215655.4849-1-chris@chris-wilson.co.uk |
|---|---|
| State | New |
| Headers | show |
| Series |
"drm/i915: Add might_sleep() check to wait_for()"
( rev:
1
)
in
Intel GFX |
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index fd64a5e8ea12..a898ded7efe9 100644 --- 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__; \ })
Chris Wilson <chris@chris-wilson.co.uk> writes: > 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> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> > --- > drivers/gpu/drm/i915/intel_drv.h | 11 ++--------- > 1 file changed, 2 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h > index fd64a5e8ea12..a898ded7efe9 100644 > --- 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__; \ > }) > -- > 2.15.0 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On 14/11/2017 21:56, Chris Wilson wrote: > 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> > --- > drivers/gpu/drm/i915/intel_drv.h | 11 ++--------- > 1 file changed, 2 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h > index fd64a5e8ea12..a898ded7efe9 100644 > --- 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__; \ > }) > Seems OK under my understanding how things work at least. Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Regards, Tvrtko
Quoting Tvrtko Ursulin (2017-11-15 09:11:13) > > On 14/11/2017 21:56, Chris Wilson wrote: > > 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> > > --- > > drivers/gpu/drm/i915/intel_drv.h | 11 ++--------- > > 1 file changed, 2 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h > > index fd64a5e8ea12..a898ded7efe9 100644 > > --- 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__; \ > > }) > > > > Seems OK under my understanding how things work at least. > > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> > Thanks for the review. Maarten also gave his r-b on irc, and with an all green pw run, pushed. We now have no more drm_can_sleep() in i915! No more in_atomic() policy violations! -Chris
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> --- drivers/gpu/drm/i915/intel_drv.h | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-)