From patchwork Fri Feb 25 07:33:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 12759743 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 417F2C433FE for ; Fri, 25 Feb 2022 07:34:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237403AbiBYHea (ORCPT ); Fri, 25 Feb 2022 02:34:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231272AbiBYHe3 (ORCPT ); Fri, 25 Feb 2022 02:34:29 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C1CF261482 for ; Thu, 24 Feb 2022 23:33:58 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id s1so6120865edd.13 for ; Thu, 24 Feb 2022 23:33:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=l/9Kn8DIMro5KQ5cQHJ53iCwxNb13sp8neXcQyO5UH4=; b=fsqWr9Z1SGRU+M7pEO1mrUt28/apHuCcsfcCbpJAbNkdUWwYsezcRpA1IuYrGKVJaS V1H795+330Ty687r4dYp9GoQm0gESlWG2i1I2yTeVneT2NRWUSb5QWBTkMVb6i5GOAEV fcdUmLejO6XfWMpHfkqcyDSoQ6eP6OAzKiNfU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=l/9Kn8DIMro5KQ5cQHJ53iCwxNb13sp8neXcQyO5UH4=; b=AoMVkmcfuDbIqskCn0Mnv8sm9BabRJWPg7YsH6J9OgLrHeT3JWbxRhOOGogRmq+t1k qpCvQ5ajZ+WbSP9wOZHMQt+Z+xhCB2ckL+eQDVXirz0zb7UExTIP588OUVpd4wJ1nF6E 3ygx2qVCMfsqPorHS72gpwl6RuHSKdAeLhOKZ5ZSgwYasPBI0JE1XPOG4mcGB7ujQuTU 6FhLJoT1v8MhRpNxOXvVMQUf0dZPiTmAvKfXVLonz++YZctsmvJl2VqEim5+JDUOMGo+ 11zJdRODS/zE3AEi3PRieZEVYdk92uELF3rLvrJN1/RLkilT9evP3cgJtVPOjTV3XbY/ krZA== X-Gm-Message-State: AOAM532Ugdu/xeZozO/CaccGsl/9orxWJHjDC5aJiX7DyrO3dkinEZFQ TgUJ4XopI+XBxZqL9AQsQaDUYlEKL7eK7Q== X-Google-Smtp-Source: ABdhPJxQESFELbwzX1YUYJHYKC0uL3v2ozopjTtnXK/VT/TH3zJ4w2ygo8youOg391P+370tqX3xaQ== X-Received: by 2002:a05:6402:1914:b0:412:d9ae:f057 with SMTP id e20-20020a056402191400b00412d9aef057mr5881556edz.446.1645774436628; Thu, 24 Feb 2022 23:33:56 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id dn14-20020a05640222ee00b00410b88abd6fsm944342edb.45.2022.02.24.23.33.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Feb 2022 23:33:56 -0800 (PST) From: Daniel Vetter To: DRI Development Cc: Daniel Vetter , Matthew Brost , Daniel Vetter , Sumit Semwal , Gustavo Padovan , =?utf-8?q?Christian_K=C3=B6nig?= , linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Subject: [PATCH] dma-fance: Add dma_fence_assert_in_signalling_section Date: Fri, 25 Feb 2022 08:33:51 +0100 Message-Id: <20220225073351.3565619-1-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Useful for checking for dma-fence signalling annotations since they don't quite nest as freely as we'd like to. Cc: Matthew Brost Signed-off-by: Daniel Vetter Cc: Sumit Semwal Cc: Gustavo Padovan Cc: "Christian König" Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/dma-buf/dma-fence.c | 19 +++++++++++++++++++ include/linux/dma-fence.h | 2 ++ 2 files changed, 21 insertions(+) diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c index 066400ed8841..2b7c3fc965e6 100644 --- a/drivers/dma-buf/dma-fence.c +++ b/drivers/dma-buf/dma-fence.c @@ -307,6 +307,25 @@ bool dma_fence_begin_signalling(void) } EXPORT_SYMBOL(dma_fence_begin_signalling); +/** + * dma_fence_assert_in_signalling_section - check fence signalling annotations + * + * Since dma_fence_begin_signalling() and dma_fence_end_signalling() are built + * using lockdep annotations they have limitations on how freely they can be + * nested. Specifically, they cannot be on both inside and outside of locked + * sections, which in practice means the annotations often have to be pushed out + * to the top level callers. + * + * To ensure low-level functions are only called with the correction + * annotations, this function can be used to check for that. + */ +void dma_fence_assert_in_signalling_section(void) +{ + if (!in_atomic()) + lockdep_assert(lock_is_held(&dma_fence_lockdep_map)); +} +EXPORT_SYMBOL(dma_fence_assert_in_signalling_section); + /** * dma_fence_end_signalling - end a critical DMA fence signalling section * @cookie: opaque cookie from dma_fence_begin_signalling() diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index 775cdc0b4f24..7179a5692f72 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -356,6 +356,7 @@ dma_fence_get_rcu_safe(struct dma_fence __rcu **fencep) #ifdef CONFIG_LOCKDEP bool dma_fence_begin_signalling(void); +void dma_fence_assert_in_signalling_section(void); void dma_fence_end_signalling(bool cookie); void __dma_fence_might_wait(void); #else @@ -363,6 +364,7 @@ static inline bool dma_fence_begin_signalling(void) { return true; } +static inline void dma_fence_assert_in_signalling_section(void) {} static inline void dma_fence_end_signalling(bool cookie) {} static inline void __dma_fence_might_wait(void) {} #endif