From: Chris Wilson Date: Wed, 9 Jan 2019 16:42:03 +0000 (+0000) Subject: drm/i915: Use mutex_lock_killable() from inside the shrinker X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3824e41975ae;p=openwrt%2Fstaging%2Fblogic.git drm/i915: Use mutex_lock_killable() from inside the shrinker If the current process is being killed (it was interrupted with SIGKILL or equivalent), it will not make any progress in page allocation and we can abort performing the shrinking on its behalf. So we can use mutex_lock_killable() instead (although this path should only be reachable from kswapd currently). Tvrtko pointed out that it should also be reachable from debugfs, which he would prefer retain its interruptiblity. As a compromise, killable is a step in the right direction! Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20190109164204.23935-1-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c index 34b108f73f1d..8ad9519779cc 100644 --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c @@ -39,18 +39,18 @@ static bool shrinker_lock(struct drm_i915_private *i915, unsigned int flags, bool *unlock) { - switch (mutex_trylock_recursive(&i915->drm.struct_mutex)) { + struct mutex *m = &i915->drm.struct_mutex; + + switch (mutex_trylock_recursive(m)) { case MUTEX_TRYLOCK_RECURSIVE: *unlock = false; return true; case MUTEX_TRYLOCK_FAILED: *unlock = false; - if (flags & I915_SHRINK_ACTIVE) { - mutex_lock_nested(&i915->drm.struct_mutex, - I915_MM_SHRINKER); + if (flags & I915_SHRINK_ACTIVE && + mutex_lock_killable_nested(m, I915_MM_SHRINKER) == 0) *unlock = true; - } return *unlock; case MUTEX_TRYLOCK_SUCCESS: