From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: [PATCH] drm/i915: Borrow our struct_mutex for the direct reclaim Date: Wed, 10 Oct 2012 16:08:59 +0100 Message-ID: <1349881739-32277-1-git-send-email-chris@chris-wilson.co.uk> References: <1349867250-22808-1-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fireflyinternet.com (smtp.fireflyinternet.com [109.228.6.236]) by gabe.freedesktop.org (Postfix) with ESMTP id 13BD6A08EB for ; Wed, 10 Oct 2012 08:09:24 -0700 (PDT) In-Reply-To: <1349867250-22808-1-git-send-email-chris@chris-wilson.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org If we have hit oom whilst holding our struct_mutex, then currently we cannot reap our own GPU buffers which likely pin most of memory, making an outright OOM more likely. So if we are running in direct reclaim and already hold the mutex, attempt to free buffers knowing that the original function can not continue until we return. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_gem.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 1d0cbfb..bed4084 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4589,6 +4589,18 @@ void i915_gem_release(struct drm_device *dev, struct drm_file *file) spin_unlock(&file_priv->mm.lock); } +static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task) +{ + if (!mutex_is_locked(mutex)) + return false; + +#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_SMP) + return mutex->owner == task; +#else + return false; +#endif +} + static int i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) { @@ -4599,10 +4611,15 @@ i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) struct drm_device *dev = dev_priv->dev; struct drm_i915_gem_object *obj; int nr_to_scan = sc->nr_to_scan; + bool unlock = true; int cnt; - if (!mutex_trylock(&dev->struct_mutex)) - return 0; + if (!mutex_trylock(&dev->struct_mutex)) { + if (mutex_is_locked_by(&dev->struct_mutex, current)) + unlock = false; + else + return 0; + } if (nr_to_scan) { nr_to_scan -= i915_gem_purge(dev_priv, nr_to_scan); @@ -4618,6 +4635,7 @@ i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) if (obj->pin_count == 0 && obj->pages_pin_count == 0) cnt += obj->base.size >> PAGE_SHIFT; - mutex_unlock(&dev->struct_mutex); + if (unlock) + mutex_unlock(&dev->struct_mutex); return cnt; } -- 1.7.10.4