While not good behaviour, it is, however, established behaviour that we can punt EAGAIN to userspace if we need to retry the ioctl. When trying to acquire a mutex, prefer to use EAGAIN to propagate losing the race so that if it does end up back in userspace, we try again.
Closes: https://gitlab.freedesktop.org/drm/intel/issues/800 Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursu...@intel.com> --- drivers/gpu/drm/i915/gt/intel_timeline.c | 2 +- drivers/gpu/drm/i915/i915_request.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c index 038e05a6336c..d71aafb66d6e 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.c +++ b/drivers/gpu/drm/i915/gt/intel_timeline.c @@ -527,7 +527,7 @@ int intel_timeline_read_hwsp(struct i915_request *from, GEM_BUG_ON(rcu_access_pointer(to->timeline) == tl); - err = -EBUSY; + err = -EAGAIN; if (mutex_trylock(&tl->mutex)) { struct intel_timeline_cacheline *cl = from->hwsp_cacheline; diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 51bb8a0812a1..fb8738987aeb 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -783,7 +783,7 @@ i915_request_await_start(struct i915_request *rq, struct i915_request *signal) if (!tl) /* already started or maybe even completed */ return 0; - fence = ERR_PTR(-EBUSY); + fence = ERR_PTR(-EAGAIN); if (mutex_trylock(&tl->mutex)) { fence = NULL; if (!i915_request_started(signal) && -- 2.24.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
