From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7E875C2D0CD for ; Mon, 19 May 2025 17:54:25 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2568510E43B; Mon, 19 May 2025 17:54:23 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="N/rkS7OO"; dkim-atps=neutral Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) by gabe.freedesktop.org (Postfix) with ESMTPS id 78E2710E4EE; Mon, 19 May 2025 17:54:21 +0000 (UTC) Received: by mail-pl1-f175.google.com with SMTP id d9443c01a7336-2320e53167dso24216115ad.3; Mon, 19 May 2025 10:54:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1747677260; x=1748282060; darn=lists.freedesktop.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=m2GLRz8JGOHg3OGSOt87e8l0+TbpKundQEHAiJsUB0Q=; b=N/rkS7OOg2jgZyVjdFoSk6fOloiox3FgFyztllvFgQX5JxsytbSi2b39w1KcirDjmr gkix21M1RCbn6U9Za73vxzo9zPOMm1iv+fJGn+FwPZNe6m+sl2T7GLrGNQgBUT81l7r/ b+57cY4z5YURpAe0ykSk2zYJuVOAcjZrHhrFCpPR6YfWb5W236EV9/QXhDPhkiQ0J3y/ nVHWo1G1M9qICWUyYjXYKQduJfGu/EOjHi2Aem26PeKlCH2tZ7T65cvb5C8DLhPTSzbW G7iqGnCKpXj1RM1QvlIlZZVFEXMDFrjaIzkuvqJ+AbPSEqSAWAGgrfPHqHUrzxU1cOdj 8JLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1747677260; x=1748282060; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=m2GLRz8JGOHg3OGSOt87e8l0+TbpKundQEHAiJsUB0Q=; b=fYiFHmXf/x6NBGHitS6mh+TQCOfw+ZVZW8wIGLWs0wrGMRNAGz/3TFnPuKgVShiQ9Q 96AC8P3bpAkeByzCu7v80rDZ6NlpPi+VoB2iUK0Vazllujqte2EtBa+/lWZ8CnW9gF2M 2DmxO5lr6RiMK90ENNgY2JBeODJZh+P2k9K9GNb/D887ewooXbVi4sGoUbZVrboKz9aX KEiKLOoKgCrtsYEG539aLkkCfb3zi0dOiLGA4DHr8d2GrAYOg9hmOblNmn74iO2CKzSi eCYnu9vD/zCz2t3eWpfKokyyadeMrQ1tzS99+VMTf/nXlVJQ1Ys8ewBtrJAmf6Iuz3qU Tc8w== X-Gm-Message-State: AOJu0YyhTcv6Two6bln/t4sQfUlOphAptFZezP3tNCEnKYaEIKYQguWr qqfEaGCwIrfBvQDR64IEEjHkgIxYDcer0qRAdpigy6JDP7r/R1SnMDxZd+9I3A== X-Gm-Gg: ASbGnctkBsOhqrZOiIhCSKW/d6bRtGQSFSV+J9Wnb+nnXmMop7ltS+++DfXVhAaYQTx YvdT8BBXl3ftGaVcd/1UT1eX6FF+eh7QM+oy/rykjI9PnWOXOkun5Xt8gZZLIOHknuxRjAXjSQF MbbWC1JCWm6+ltUXN4sonnaU+j1qc8a9+oQl85tomxvkwFWbbXMmYCpq98wWF9J/xGrwuOq9DZR QFAkKTpCmmRYwpcmvFaXJAhkRTLFLrprjZNuDJBaC91Ti0R1XMwExxlQjfrX9Wr5VH5k/vpqJiJ gBgPGIV97pxinCOqNcvhsA3D7tq0bXacnAFielQaPxAeOXVQEmIq5CeCVpAguBTdImef2YmyPGx Rpwf45upvDOdgkHzmIuDXXJpgUQ== X-Google-Smtp-Source: AGHT+IH2WqLWtOHrqBPUnezx4TsYoSZdJNpBSBzObXgLOEWBSEBtNE7MpDGnat/hGDNWJDd8wLzYpg== X-Received: by 2002:a17:902:e788:b0:22e:8560:46ff with SMTP id d9443c01a7336-231d452db9fmr167399335ad.27.1747677260497; Mon, 19 May 2025 10:54:20 -0700 (PDT) Received: from localhost ([2a00:79e0:3e00:2601:3afc:446b:f0df:eadc]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-231d4ac93besm62433505ad.12.2025.05.19.10.54.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 May 2025 10:54:19 -0700 (PDT) From: Rob Clark To: dri-devel@lists.freedesktop.org Cc: freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, Connor Abbott , Rob Clark , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Clark , Abhinav Kumar , Dmitry Baryshkov , Sean Paul , Marijn Suijten , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v5 03/40] drm/gem: Add ww_acquire_ctx support to drm_gem_lru_scan() Date: Mon, 19 May 2025 10:51:26 -0700 Message-ID: <20250519175348.11924-4-robdclark@gmail.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250519175348.11924-1-robdclark@gmail.com> References: <20250519175348.11924-1-robdclark@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Rob Clark If the callback is going to have to attempt to grab more locks, it is useful to have an ww_acquire_ctx to avoid locking order problems. Why not use the drm_exec helper instead? Mainly because (a) where ww_acquire_init() is called is awkward, and (b) we don't really need to retry after backoff, we can just move on to the next object. Signed-off-by: Rob Clark --- drivers/gpu/drm/drm_gem.c | 14 +++++++++++--- drivers/gpu/drm/msm/msm_gem_shrinker.c | 24 +++++++++++++----------- include/drm/drm_gem.h | 10 ++++++---- 3 files changed, 30 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index c6240bab3fa5..c8f983571c70 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1460,12 +1460,14 @@ EXPORT_SYMBOL(drm_gem_lru_move_tail); * @nr_to_scan: The number of pages to try to reclaim * @remaining: The number of pages left to reclaim, should be initialized by caller * @shrink: Callback to try to shrink/reclaim the object. + * @ticket: Optional ww_acquire_ctx context to use for locking */ unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned int nr_to_scan, unsigned long *remaining, - bool (*shrink)(struct drm_gem_object *obj)) + bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket), + struct ww_acquire_ctx *ticket) { struct drm_gem_lru still_in_lru; struct drm_gem_object *obj; @@ -1498,17 +1500,20 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, */ mutex_unlock(lru->lock); + if (ticket) + ww_acquire_init(ticket, &reservation_ww_class); + /* * Note that this still needs to be trylock, since we can * hit shrinker in response to trying to get backing pages * for this obj (ie. while it's lock is already held) */ - if (!dma_resv_trylock(obj->resv)) { + if (!ww_mutex_trylock(&obj->resv->lock, ticket)) { *remaining += obj->size >> PAGE_SHIFT; goto tail; } - if (shrink(obj)) { + if (shrink(obj, ticket)) { freed += obj->size >> PAGE_SHIFT; /* @@ -1522,6 +1527,9 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, dma_resv_unlock(obj->resv); + if (ticket) + ww_acquire_fini(ticket); + tail: drm_gem_object_put(obj); mutex_lock(lru->lock); diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c index 07ca4ddfe4e3..de185fc34084 100644 --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c @@ -44,7 +44,7 @@ msm_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc) } static bool -purge(struct drm_gem_object *obj) +purge(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (!is_purgeable(to_msm_bo(obj))) return false; @@ -58,7 +58,7 @@ purge(struct drm_gem_object *obj) } static bool -evict(struct drm_gem_object *obj) +evict(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (is_unevictable(to_msm_bo(obj))) return false; @@ -79,21 +79,21 @@ wait_for_idle(struct drm_gem_object *obj) } static bool -active_purge(struct drm_gem_object *obj) +active_purge(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (!wait_for_idle(obj)) return false; - return purge(obj); + return purge(obj, ticket); } static bool -active_evict(struct drm_gem_object *obj) +active_evict(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (!wait_for_idle(obj)) return false; - return evict(obj); + return evict(obj, ticket); } static unsigned long @@ -102,7 +102,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) struct msm_drm_private *priv = shrinker->private_data; struct { struct drm_gem_lru *lru; - bool (*shrink)(struct drm_gem_object *obj); + bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket); bool cond; unsigned long freed; unsigned long remaining; @@ -122,8 +122,9 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) continue; stages[i].freed = drm_gem_lru_scan(stages[i].lru, nr, - &stages[i].remaining, - stages[i].shrink); + &stages[i].remaining, + stages[i].shrink, + NULL); nr -= stages[i].freed; freed += stages[i].freed; remaining += stages[i].remaining; @@ -164,7 +165,7 @@ msm_gem_shrinker_shrink(struct drm_device *dev, unsigned long nr_to_scan) static const int vmap_shrink_limit = 15; static bool -vmap_shrink(struct drm_gem_object *obj) +vmap_shrink(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket) { if (!is_vunmapable(to_msm_bo(obj))) return false; @@ -192,7 +193,8 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr) unmapped += drm_gem_lru_scan(lrus[idx], vmap_shrink_limit - unmapped, &remaining, - vmap_shrink); + vmap_shrink, + NULL); } *(unsigned long *)ptr += unmapped; diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index bcd54020d6ba..b611a9482abf 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -556,10 +556,12 @@ void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock); void drm_gem_lru_remove(struct drm_gem_object *obj); void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj); void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj); -unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, - unsigned int nr_to_scan, - unsigned long *remaining, - bool (*shrink)(struct drm_gem_object *obj)); +unsigned long +drm_gem_lru_scan(struct drm_gem_lru *lru, + unsigned int nr_to_scan, + unsigned long *remaining, + bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket), + struct ww_acquire_ctx *ticket); int drm_gem_evict(struct drm_gem_object *obj); -- 2.49.0