4.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
commit 636deb5b2277cf57bb0f5e00fc9687de9a96061e upstream.
The i915_gem_object_wait_fence() uses an incoming timeout=0 to query
whether the current fence is busy or idle, without waiting. This can be
used by the wait-ioctl to implement a busy query.
Fixes: e95433c73a11 ("drm/i915: Rearrange i915_wait_request() accounting with callers")
Testcase: igt/gem_wait/basic-busy-write-all
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Matthew Auld <matthew.william.auld@xxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: <drm-intel-fixes@xxxxxxxxxxxxxxxxxxxxx> # v4.10-rc1+
Link: http://patchwork.freedesktop.org/patch/msgid/20170212215344.16600-1-chris@xxxxxxxxxxxxxxxxxx
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
(cherry picked from commit d892e9398ecf6defc7972a62227b77dad6be20bd)
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/i915_gem.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -440,7 +440,7 @@ i915_gem_object_wait_reservation(struct
timeout = i915_gem_object_wait_fence(shared[i],
flags, timeout,
rps);
- if (timeout <= 0)
+ if (timeout < 0)
break;
dma_fence_put(shared[i]);
@@ -453,7 +453,7 @@ i915_gem_object_wait_reservation(struct
excl = reservation_object_get_excl_rcu(resv);
}
- if (excl && timeout > 0)
+ if (excl && timeout >= 0)
timeout = i915_gem_object_wait_fence(excl, flags, timeout, rps);
dma_fence_put(excl);