From 556b748710586afa24a696ba81fe89dc7f41cebd Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 14 Nov 2016 20:40:56 +0000 Subject: drm/i915: Give each sw_fence its own lockclass Localise the static struct lock_class_key to the caller of i915_sw_fence_init() so that we create a lock_class instance for each unique sw_fence rather than all sw_fences sharing the same lock_class. This eliminate some lockdep false positive when using fences from within fence callbacks. For the relatively small number of fences currently in use [2], this adds 160 bytes of unused text/code when lockdep is disabled. This seems quite high, but fully reducing it via ifdeffery is also quite ugly. Removing the #fence strings saves 72 bytes with just a single #ifdef. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20161114204105.29171-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_sw_fence.h | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915/i915_sw_fence.h') diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h b/drivers/gpu/drm/i915/i915_sw_fence.h index 707dfc4f0da5..7508d23f823b 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.h +++ b/drivers/gpu/drm/i915/i915_sw_fence.h @@ -40,7 +40,22 @@ typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *, enum i915_sw_fence_notify state); #define __i915_sw_fence_call __aligned(4) -void i915_sw_fence_init(struct i915_sw_fence *fence, i915_sw_fence_notify_t fn); +void __i915_sw_fence_init(struct i915_sw_fence *fence, + i915_sw_fence_notify_t fn, + const char *name, + struct lock_class_key *key); +#ifdef CONFIG_LOCKDEP +#define i915_sw_fence_init(fence, fn) \ +do { \ + static struct lock_class_key __key; \ + \ + __i915_sw_fence_init((fence), (fn), #fence, &__key); \ +} while (0) +#else +#define i915_sw_fence_init(fence, fn) \ + __i915_sw_fence_init((fence), (fn), NULL, NULL) +#endif + void i915_sw_fence_commit(struct i915_sw_fence *fence); int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence, -- cgit