From patchwork Wed Dec 12 13:41:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10726377 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A1D7714E2 for ; Wed, 12 Dec 2018 13:42:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 913032B18A for ; Wed, 12 Dec 2018 13:42:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8591B2B1FF; Wed, 12 Dec 2018 13:42:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2E2C32B18A for ; Wed, 12 Dec 2018 13:42:23 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 514036E6F2; Wed, 12 Dec 2018 13:42:21 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id C16D26E6F5 for ; Wed, 12 Dec 2018 13:42:13 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 14880790-1500050 for multiple; Wed, 12 Dec 2018 13:41:57 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Wed, 12 Dec 2018 13:41:31 +0000 Message-Id: <20181212134149.26981-2-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.0.rc2 In-Reply-To: <20181212134149.26981-1-chris@chris-wilson.co.uk> References: <20181212134149.26981-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 01/19] drm/i915: Return immediately if trylock fails for direct-reclaim X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Ignore trying to shrink from i915 if we fail to acquire the struct_mutex in the shrinker while performing direct-reclaim. The trade-off being (much) lower latency for non-i915 clients at an increased risk of being unable to obtain a page from direct-reclaim without hitting the oom-notifier. The proviso being that we still keep trying to hard obtain the lock for oom so that we can reap under heavy memory pressure. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_drv.h | 4 ++-- drivers/gpu/drm/i915/i915_gem_shrinker.c | 24 +++++++++++------------- 2 files changed, 13 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index e70707e79386..53f16b037f62 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2915,9 +2915,9 @@ i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj) __i915_gem_object_unpin_pages(obj); } -enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock */ +enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock/struct_mutex */ I915_MM_NORMAL = 0, - I915_MM_SHRINKER + I915_MM_SHRINKER /* called "recursively" from direct-reclaim-esque */ }; void __i915_gem_object_put_pages(struct drm_i915_gem_object *obj, diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c index ea90d3a0d511..d461f458f4af 100644 --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c @@ -36,7 +36,9 @@ #include "i915_drv.h" #include "i915_trace.h" -static bool shrinker_lock(struct drm_i915_private *i915, bool *unlock) +static bool shrinker_lock(struct drm_i915_private *i915, + unsigned int flags, + bool *unlock) { switch (mutex_trylock_recursive(&i915->drm.struct_mutex)) { case MUTEX_TRYLOCK_RECURSIVE: @@ -45,15 +47,11 @@ static bool shrinker_lock(struct drm_i915_private *i915, bool *unlock) case MUTEX_TRYLOCK_FAILED: *unlock = false; - preempt_disable(); - do { - cpu_relax(); - if (mutex_trylock(&i915->drm.struct_mutex)) { - *unlock = true; - break; - } - } while (!need_resched()); - preempt_enable(); + if (flags & I915_SHRINK_ACTIVE) { + mutex_lock_nested(&i915->drm.struct_mutex, + I915_MM_SHRINKER); + *unlock = true; + } return *unlock; case MUTEX_TRYLOCK_SUCCESS: @@ -160,7 +158,7 @@ i915_gem_shrink(struct drm_i915_private *i915, unsigned long scanned = 0; bool unlock; - if (!shrinker_lock(i915, &unlock)) + if (!shrinker_lock(i915, flags, &unlock)) return 0; /* @@ -357,7 +355,7 @@ i915_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) sc->nr_scanned = 0; - if (!shrinker_lock(i915, &unlock)) + if (!shrinker_lock(i915, 0, &unlock)) return SHRINK_STOP; freed = i915_gem_shrink(i915, @@ -397,7 +395,7 @@ shrinker_lock_uninterruptible(struct drm_i915_private *i915, bool *unlock, do { if (i915_gem_wait_for_idle(i915, 0, MAX_SCHEDULE_TIMEOUT) == 0 && - shrinker_lock(i915, unlock)) + shrinker_lock(i915, 0, unlock)) break; schedule_timeout_killable(1);