As we may have to iterate a few thousand elements to acquire and release
the shmemfs backing storage for a GPU object, we need to break up the
long loop with cond_resched() to retain a modicum of low latency for
other processes.
Testcase: igt/benchmarks/gem_syslatency
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Kuo-Hsin Yang <vovoy@xxxxxxxxxxxx>
Cc: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/i915_gem.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index b1caff07ed65..a120112d0621 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2404,6 +2404,7 @@ i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj,
mark_page_accessed(page);
put_page(page);
+ cond_resched();
}
obj->mm.dirty = false;
@@ -2574,6 +2575,7 @@ static int i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
gfp_t gfp = noreclaim;
do {
+ cond_resched();
page = shmem_read_mapping_page_gfp(mapping, i, gfp);
if (likely(!IS_ERR(page)))
break;
@@ -2584,7 +2586,6 @@ static int i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
}
i915_gem_shrink(dev_priv, 2 * page_count, NULL, *s++);
- cond_resched();
/*
* We've tried hard to allocate the memory by reaping
--
2.19.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
