From e4e80625300390d8846b72d7076fd1a75af6ea60 Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Thu, 16 Dec 2021 15:27:34 +0100 Subject: [PATCH] drm/i915: Change shrink ordering to use locking around unbinding. Call drop_pages with the gem object lock held, instead of the other way around. This will allow us to drop the vma bindings with the gem object lock held. We plan to require the object lock for unpinning in the future, and this is an easy target. Signed-off-by: Maarten Lankhorst Reviewed-by: Niranjana Vishwanathapura Link: https://patchwork.freedesktop.org/patch/msgid/20211216142749.1966107-3-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/i915/gem/i915_gem_shrinker.c | 38 +++++++++++++--------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c index 05a1ba2..6003db8 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c @@ -36,8 +36,8 @@ static bool can_release_pages(struct drm_i915_gem_object *obj) return swap_available() || obj->mm.madv == I915_MADV_DONTNEED; } -static bool unsafe_drop_pages(struct drm_i915_gem_object *obj, - unsigned long shrink, bool trylock_vm) +static int drop_pages(struct drm_i915_gem_object *obj, + unsigned long shrink, bool trylock_vm) { unsigned long flags; @@ -214,26 +214,24 @@ i915_gem_shrink(struct i915_gem_ww_ctx *ww, spin_unlock_irqrestore(&i915->mm.obj_lock, flags); - err = 0; - if (unsafe_drop_pages(obj, shrink, trylock_vm)) { - /* May arrive from get_pages on another bo */ - if (!ww) { - if (!i915_gem_object_trylock(obj)) - goto skip; - } else { - err = i915_gem_object_lock(obj, ww); - if (err) - goto skip; - } - - if (!__i915_gem_object_put_pages(obj)) { - if (!try_to_writeback(obj, shrink)) - count += obj->base.size >> PAGE_SHIFT; - } - if (!ww) - i915_gem_object_unlock(obj); + /* May arrive from get_pages on another bo */ + if (!ww) { + if (!i915_gem_object_trylock(obj)) + goto skip; + } else { + err = i915_gem_object_lock(obj, ww); + if (err) + goto skip; } + if (drop_pages(obj, shrink, trylock_vm) && + !__i915_gem_object_put_pages(obj) && + !try_to_writeback(obj, shrink)) + count += obj->base.size >> PAGE_SHIFT; + + if (!ww) + i915_gem_object_unlock(obj); + scanned += obj->base.size >> PAGE_SHIFT; skip: i915_gem_object_put(obj); -- 2.7.4