| Message ID | 1352451530-10767-1-git-send-email-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 09, 2012 at 08:58:50AM +0000, Chris Wilson wrote: > In the circumstances that the shrinker is allowed to steal the mutex > in order to reap pages, we need to be careful to prevent it operating on > the current object and shooting ourselves in the foot. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Ok, I this is definitely the major one that I've thought of, but I think I've found another place that need a similar treatment: i915_gem_fault: In between bind_to_gtt and vm_insert_pfn we have a call to get_fence, which might potentially call kmalloc due to a pending request. I know, it's highly unlikely that this will ever matter, but I think if we braket this with a pin/unpin, it will nicely serve as a reminder where to reserve/unreserve and object, in case we ever switch to a per-object locking scheme. Otherwise I can't poke holes into this any more ... Cheers, Daniel > --- > drivers/gpu/drm/i915/i915_gem.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > index 159dca5..f225583 100644 > --- a/drivers/gpu/drm/i915/i915_gem.c > +++ b/drivers/gpu/drm/i915/i915_gem.c > @@ -3091,6 +3091,8 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, > if (ret) > return ret; > > + i915_gem_object_pin_pages(obj); > + > search_free: > if (map_and_fenceable) > free_space = > @@ -3121,14 +3123,17 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, > obj->cache_level, > map_and_fenceable, > nonblocking); > - if (ret) > + if (ret) { > + i915_gem_object_unpin_pages(obj); > return ret; > + } > > goto search_free; > } > if (WARN_ON(!i915_gem_valid_gtt_space(dev, > obj->gtt_space, > obj->cache_level))) { > + i915_gem_object_unpin_pages(obj); > drm_mm_put_block(obj->gtt_space); > obj->gtt_space = NULL; > return -EINVAL; > @@ -3137,6 +3142,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, > > ret = i915_gem_gtt_prepare_object(obj); > if (ret) { > + i915_gem_object_unpin_pages(obj); > drm_mm_put_block(obj->gtt_space); > obj->gtt_space = NULL; > return ret; > @@ -3159,6 +3165,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, > > obj->map_and_fenceable = mappable && fenceable; > > + i915_gem_object_unpin_pages(obj); > trace_i915_gem_object_bind(obj, map_and_fenceable); > i915_gem_verify_gtt(dev); > return 0; > -- > 1.7.10.4 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 159dca5..f225583 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3091,6 +3091,8 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, if (ret) return ret; + i915_gem_object_pin_pages(obj); + search_free: if (map_and_fenceable) free_space = @@ -3121,14 +3123,17 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, obj->cache_level, map_and_fenceable, nonblocking); - if (ret) + if (ret) { + i915_gem_object_unpin_pages(obj); return ret; + } goto search_free; } if (WARN_ON(!i915_gem_valid_gtt_space(dev, obj->gtt_space, obj->cache_level))) { + i915_gem_object_unpin_pages(obj); drm_mm_put_block(obj->gtt_space); obj->gtt_space = NULL; return -EINVAL; @@ -3137,6 +3142,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, ret = i915_gem_gtt_prepare_object(obj); if (ret) { + i915_gem_object_unpin_pages(obj); drm_mm_put_block(obj->gtt_space); obj->gtt_space = NULL; return ret; @@ -3159,6 +3165,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, obj->map_and_fenceable = mappable && fenceable; + i915_gem_object_unpin_pages(obj); trace_i915_gem_object_bind(obj, map_and_fenceable); i915_gem_verify_gtt(dev); return 0;
In the circumstances that the shrinker is allowed to steal the mutex in order to reap pages, we need to be careful to prevent it operating on the current object and shooting ourselves in the foot. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_gem.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)