From patchwork Mon Aug 16 08:48:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 12437965 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 888BAC4338F for ; Mon, 16 Aug 2021 08:49:22 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 29CDF61B2F for ; Mon, 16 Aug 2021 08:49:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 29CDF61B2F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D1CBB89CB2; Mon, 16 Aug 2021 08:49:19 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id C848089CAF; Mon, 16 Aug 2021 08:49:17 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10077"; a="215820804" X-IronPort-AV: E=Sophos;i="5.84,324,1620716400"; d="scan'208";a="215820804" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2021 01:49:16 -0700 X-IronPort-AV: E=Sophos;i="5.84,324,1620716400"; d="scan'208";a="592581225" Received: from vanderss-mobl.ger.corp.intel.com (HELO thellstr-mobl1.intel.com) ([10.249.254.118]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2021 01:49:12 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Maarten Lankhorst Date: Mon, 16 Aug 2021 10:48:55 +0200 Message-Id: <20210816084855.75586-1-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915: Ditch the i915_gem_ww_ctx loop member X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 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" It's only used by the for_i915_gem_ww() macro and we can use the (typically) on-stack _err variable in its place. While initially setting the _err variable to -EDEADLK to enter the loop, we clear it before actually entering using fetch_and_zero() to avoid empty loops or code not setting the _err variable running forever. Suggested-by: Maarten Lankhorst Signed-off-by: Thomas Hellström --- drivers/gpu/drm/i915/i915_gem_ww.h | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_ww.h b/drivers/gpu/drm/i915/i915_gem_ww.h index f6b1a796667b..98348b1e6182 100644 --- a/drivers/gpu/drm/i915/i915_gem_ww.h +++ b/drivers/gpu/drm/i915/i915_gem_ww.h @@ -7,12 +7,13 @@ #include +#include "i915_utils.h" + struct i915_gem_ww_ctx { struct ww_acquire_ctx ctx; struct list_head obj_list; struct drm_i915_gem_object *contended; - unsigned short intr; - unsigned short loop; + bool intr; }; void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ctx, bool intr); @@ -23,28 +24,20 @@ void i915_gem_ww_unlock_single(struct drm_i915_gem_object *obj); /* Internal functions used by the inlines! Don't use. */ static inline int __i915_gem_ww_fini(struct i915_gem_ww_ctx *ww, int err) { - ww->loop = 0; if (err == -EDEADLK) { err = i915_gem_ww_ctx_backoff(ww); if (!err) - ww->loop = 1; + err = -EDEADLK; } - if (!ww->loop) + if (err != -EDEADLK) i915_gem_ww_ctx_fini(ww); return err; } -static inline void -__i915_gem_ww_init(struct i915_gem_ww_ctx *ww, bool intr) -{ - i915_gem_ww_ctx_init(ww, intr); - ww->loop = 1; -} - -#define for_i915_gem_ww(_ww, _err, _intr) \ - for (__i915_gem_ww_init(_ww, _intr); (_ww)->loop; \ +#define for_i915_gem_ww(_ww, _err, _intr) \ + for (i915_gem_ww_ctx_init(_ww, _intr), (_err) = -EDEADLK; \ + fetch_and_zero(&_err) == -EDEADLK; \ _err = __i915_gem_ww_fini(_ww, _err)) - #endif