Re: [PATCH v2 1/3] drm/i915: Drop racy markup of missed-irqs from idle-worker

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 21/07/16 11:10, Chris Wilson wrote:
On Thu, Jul 21, 2016 at 10:58:05AM +0100, Tvrtko Ursulin wrote:

On 21/07/16 07:57, Chris Wilson wrote:
During the idle-worker we disable the hangcheck and so kick any waiters
that should have been completed (since the GPU is now idle). Unlike the
hangcheck, we do not take any care to avoid the race between the irq
handler and ourselves, and so it is possible for us to declare a missed
interrupt even as the bottom-half is being scheduled to run. Let's
ignore this race to stop a potential false-positive error.

If the bottom half is scheduled to run then then..

References: https://bugs.freedesktop.org/show_bug.cgi?id=96974
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx>
---
  drivers/gpu/drm/i915/i915_gem.c | 7 +++----
  1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 40047eb48826..9e826585edb2 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2706,10 +2706,9 @@ i915_gem_idle_work_handler(struct work_struct *work)
  	rearm_hangcheck = false;

  	stuck_engines = intel_kick_waiters(dev_priv);

... this will not return a stucked engine since the there is a bh
task assigned all until the bh exits.

It reports if it wakes up a waiter on any engine. If the bh is already
running, we cannot know if it has missed the seqno update. If it isn't
running yet, we cannot know if it is about to be run.

Oh I read the logic as completely opposite than what it is.

Since the idle worker runs 100ms after last retirement, that would mean a really slow waiter or what?

Regards,

Tvrtko

_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux