From: Kenneth Graunke <kenneth@whitecape.org>
Date: Mon, 17 Jul 2017 19:57:20 +0000 (-0700)
Subject: i965/bufmgr: Skip wait ioctl when not busy.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=bdae2ddff89004c199b71cb6a4a306dee616f7f9;p=mesa.git

i965/bufmgr: Skip wait ioctl when not busy.

If the buffer is idle, we I915_GEM_WAIT will return immediately,
so we may as well skip the ioctl altogether.  We can't trust the
"idle" flag for external buffers, but for most, it should be fine.

Reviewed-by: Matt Turner <mattst88@gmail.com>
---

diff --git a/src/mesa/drivers/dri/i965/brw_bufmgr.c b/src/mesa/drivers/dri/i965/brw_bufmgr.c
index fc2a2276236..5edf4626b4f 100644
--- a/src/mesa/drivers/dri/i965/brw_bufmgr.c
+++ b/src/mesa/drivers/dri/i965/brw_bufmgr.c
@@ -924,6 +924,10 @@ brw_bo_wait(struct brw_bo *bo, int64_t timeout_ns)
    struct drm_i915_gem_wait wait;
    int ret;
 
+   /* If we know it's idle, don't bother with the kernel round trip */
+   if (bo->idle && !bo->external)
+      return 0;
+
    memclear(wait);
    wait.bo_handle = bo->gem_handle;
    wait.timeout_ns = timeout_ns;