From patchwork Wed Mar 17 22:19:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12147051 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 7DAA0C433E6 for ; Wed, 17 Mar 2021 22:19:53 +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 F3A1964DE7 for ; Wed, 17 Mar 2021 22:19:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F3A1964DE7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=jlekstrand.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0CD0F6E042; Wed, 17 Mar 2021 22:19:50 +0000 (UTC) Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by gabe.freedesktop.org (Postfix) with ESMTPS id 794F06E042 for ; Wed, 17 Mar 2021 22:19:48 +0000 (UTC) Received: by mail-pj1-x1033.google.com with SMTP id kr3-20020a17090b4903b02900c096fc01deso2071854pjb.4 for ; Wed, 17 Mar 2021 15:19:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlekstrand-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Wcain8isGpID5TiDS3p2A/N5+StUg6lfh0Vw4Kh3Acs=; b=UsHFgzz+c5uMKF8Wf47y6Ns4m/UqzroCvcVPXsje8RN1O16WEXQU7xqHuUmJBGM2wj JVcYcgVKlWb5oPAtsnQYfRLJRDnXIK4HieG8BaEJJZTHM2/TaN4EM/gKcNEIQIPs52CR Sm8B+8k+elFgdUj9id4iddlzyiw//ddR9Twy0SfDTv0A+kupihKtO65aRgJI214YASTh Hz+4qGv7AJLaRMEEyz9JhqkiEhkb3uncK8Q2JzyM1p5BBcocIXblEQtLxWI9qlQskkxL LW02ZBBW2psd+FGx3pCYOYmaSnFs8NLJup0ZVJMYPel6e03837JsXfWmWpI9GbnNlDXD ZPLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Wcain8isGpID5TiDS3p2A/N5+StUg6lfh0Vw4Kh3Acs=; b=YQ+XwpRlAEf4PmQ2reN/LtnRvI+wHhhSB64rgSk3V4mPVIxGU/M41Ecwy5bXFu9SQh L1Ssjjb7Ob3muIW6QjdHRVrCLl2A1xlUR99xJwSNP+CmelTMgaLnxfYs7PhIR0ca8rus qI94ApJITg3gio9h4moV9jHC3/gHowCrl6r2ptRuk0EVcyAgOZgUiGGkUXkNq1QQAC3J kveo/ZM8HmoE/WaCcDsmCfQK6nRLQTIhzm4OGxNlkAioy/B4okq/vkbfB6PEH9Z30Igj 2jzQVOP1z4itdpfeYTQx7qc1/7Ec/l4HqlK/A4rRm9SrIiBKzUeMPAVDwDXBrSivbcTD vEIw== X-Gm-Message-State: AOAM532N5nk5S6NeqbwX7Yylz6qzJnmLnWmDbdrksFxliYUz9esRtdXd WAv915W/qef8Cdf6NN7G3iYQN7cq9pWjEw== X-Google-Smtp-Source: ABdhPJzQa3s70qbW+9g3e4UAaoBFAdAKB+bWcNRluk0TxMtceeKF5ozpjRubl3hF0DaPCTv+27uEhw== X-Received: by 2002:a17:90b:3449:: with SMTP id lj9mr1012983pjb.55.1616019587704; Wed, 17 Mar 2021 15:19:47 -0700 (PDT) Received: from omlet.lan (jfdmzpr05-ext.jf.intel.com. [134.134.139.74]) by smtp.gmail.com with ESMTPSA id l19sm117708pjt.16.2021.03.17.15.19.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Mar 2021 15:19:47 -0700 (PDT) From: Jason Ekstrand To: dri-devel@lists.freedesktop.org Subject: [PATCH 1/3] dma-buf: add dma_fence_array_for_each (v2) Date: Wed, 17 Mar 2021 17:19:38 -0500 Message-Id: <20210317221940.2146688-2-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210317221940.2146688-1-jason@jlekstrand.net> References: <20210316045322.2020294-1-jason@jlekstrand.net> <20210317221940.2146688-1-jason@jlekstrand.net> MIME-Version: 1.0 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: , Cc: =?utf-8?q?Christian_K=C3=B6nig?= , Jason Ekstrand Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Christian König Add a helper to iterate over all fences in a dma_fence_array object. v2 (Jason Ekstrand) - Return NULL from dma_fence_array_first if head == NULL. This matches the iterator behavior of dma_fence_chain_for_each in that it iterates zero times if head == NULL. - Return NULL from dma_fence_array_next if index > array->num_fences. Signed-off-by: Jason Ekstrand --- drivers/dma-buf/dma-fence-array.c | 27 +++++++++++++++++++++++++++ include/linux/dma-fence-array.h | 17 +++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c index d3fbd950be944..2ac1afc697d0f 100644 --- a/drivers/dma-buf/dma-fence-array.c +++ b/drivers/dma-buf/dma-fence-array.c @@ -201,3 +201,30 @@ bool dma_fence_match_context(struct dma_fence *fence, u64 context) return true; } EXPORT_SYMBOL(dma_fence_match_context); + +struct dma_fence *dma_fence_array_first(struct dma_fence *head) +{ + struct dma_fence_array *array; + + if (!head) + return NULL; + + array = to_dma_fence_array(head); + if (!array) + return head; + + return array->fences[0]; +} +EXPORT_SYMBOL(dma_fence_array_first); + +struct dma_fence *dma_fence_array_next(struct dma_fence *head, + unsigned int index) +{ + struct dma_fence_array *array = to_dma_fence_array(head); + + if (!array || index >= array->num_fences) + return NULL; + + return array->fences[index]; +} +EXPORT_SYMBOL(dma_fence_array_next); diff --git a/include/linux/dma-fence-array.h b/include/linux/dma-fence-array.h index 303dd712220fd..588ac8089dd61 100644 --- a/include/linux/dma-fence-array.h +++ b/include/linux/dma-fence-array.h @@ -74,6 +74,19 @@ to_dma_fence_array(struct dma_fence *fence) return container_of(fence, struct dma_fence_array, base); } +/** + * dma_fence_array_for_each - iterate over all fences in array + * @fence: current fence + * @index: index into the array + * @head: potential dma_fence_array object + * + * Test if @array is a dma_fence_array object and if yes iterate over all fences + * in the array. If not just iterate over the fence in @array itself. + */ +#define dma_fence_array_for_each(fence, index, head) \ + for (index = 0, fence = dma_fence_array_first(head); fence; \ + ++(index), fence = dma_fence_array_next(head, index)) + struct dma_fence_array *dma_fence_array_create(int num_fences, struct dma_fence **fences, u64 context, unsigned seqno, @@ -81,4 +94,8 @@ struct dma_fence_array *dma_fence_array_create(int num_fences, bool dma_fence_match_context(struct dma_fence *fence, u64 context); +struct dma_fence *dma_fence_array_first(struct dma_fence *head); +struct dma_fence *dma_fence_array_next(struct dma_fence *head, + unsigned int index); + #endif /* __LINUX_DMA_FENCE_ARRAY_H */ From patchwork Wed Mar 17 22:19:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12147053 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 C7608C433E0 for ; Wed, 17 Mar 2021 22:19:56 +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 5FF7064F20 for ; Wed, 17 Mar 2021 22:19:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5FF7064F20 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=jlekstrand.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9D1776E047; Wed, 17 Mar 2021 22:19:52 +0000 (UTC) Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by gabe.freedesktop.org (Postfix) with ESMTPS id 925F56E048 for ; Wed, 17 Mar 2021 22:19:50 +0000 (UTC) Received: by mail-pg1-x535.google.com with SMTP id y27so131968pga.9 for ; Wed, 17 Mar 2021 15:19:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlekstrand-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=r9RCUmX1dma+8m+9py1IfH9xn4V00HXuvse/jejKM1I=; b=VTbEcR70LUWhphik2UQ5VhtH6Yg3XCmIy/+T65GOkpI2yCTz8wzOCqlvHJC3AS9Rg2 4pDOM0BeRt/BDxATlEfEd5UQdGt5bLcPEqP4zuUp2BbBcWymKONN2gd7RTKAgcFdOKAH Z+kP+mRPcMc3Ec/fiDnup1yi20hWPo+yPHnlr4mE8Yb0yufd5BM0UeRIGsvxH72fkQlR f8ND4O95hES8HTQLTnNl4fLRBdSeBFUtgBNN5KlOPmcqrlxCCOXA3AyednKwORh0j4AJ SkvjFG6Iu9YZ42LIZz5jaQoydjHC1QXycIKI/WqIvItoYNh/pgopGcdPW7uRuXg2W8qn Ormg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=r9RCUmX1dma+8m+9py1IfH9xn4V00HXuvse/jejKM1I=; b=LJf0ovW8n+Qp/69Bs+BQ5JqDFj5Hmqwk0C9t8tuY6tS2iYNNSU6LrnB5ES9BWzTIjr nIkXJ7wMJdkg99+Y2chxyXYMXuo3AHLY3STrP6YegSS7OmycLMqBQDNKNbCeZrT57wxJ yZ+ifwksHKmS06fO84BpbtbmrQhZ+dGePXRY1qD5ldCMaUkDu3tFaWp/8lJsKJoNW2Hx EeLN0ZNurtGwLhqw/Px52Vw+AkGH8ch81wPryWp0/CGAvm0ezjOsOLhUOu37S2QdW0OS iWBAZDcVsO5+xxA2QGB29LkJ2hVTaPahNJEebpG58Nc2pdS8Z/63ypTLKjNOKXtPOoxL gi7A== X-Gm-Message-State: AOAM531b9nUECeNn9hulPvx6Uv5a8eG3BbcPDA6EbiOipExQQjuIu5Wm qESNhJWbdCt05VKQpJHsUzsjryVd5SXQww== X-Google-Smtp-Source: ABdhPJyN6YHo9Cc4iNfZ2g1PlXhc4k2dpE98aPk8Jev2usbTqDSOiEly7dUiaPGaCHTYq29ge6tyLg== X-Received: by 2002:a05:6a00:ad1:b029:1ec:c826:55aa with SMTP id c17-20020a056a000ad1b02901ecc82655aamr1053928pfl.26.1616019589581; Wed, 17 Mar 2021 15:19:49 -0700 (PDT) Received: from omlet.lan (jfdmzpr05-ext.jf.intel.com. [134.134.139.74]) by smtp.gmail.com with ESMTPSA id l19sm117708pjt.16.2021.03.17.15.19.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Mar 2021 15:19:49 -0700 (PDT) From: Jason Ekstrand To: dri-devel@lists.freedesktop.org Subject: [PATCH 2/3] dma-buf: add dma_resv_get_singleton_rcu (v3) Date: Wed, 17 Mar 2021 17:19:39 -0500 Message-Id: <20210317221940.2146688-3-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210317221940.2146688-1-jason@jlekstrand.net> References: <20210316045322.2020294-1-jason@jlekstrand.net> <20210317221940.2146688-1-jason@jlekstrand.net> MIME-Version: 1.0 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: , Cc: Jason Ekstrand Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Add a helper function to get a single fence representing all fences in a dma_resv object. This fence is either the only one in the object or all not signaled fences of the object in a flatted out dma_fence_array. v2 (Jason Ekstrand): - Take reference of fences both for creating the dma_fence_array and in the case where we return one fence. - Handle the case where dma_resv_get_list() returns NULL v3 (Jason Ekstrand): - Add an _rcu suffix because it is read-only - Rewrite to use dma_resv_get_fences_rcu so it's RCU-safe - Add an EXPORT_SYMBOL_GPL declaration - Re-author the patch to Jason since very little is left of Christian König's original patch Signed-off-by: Jason Ekstrand --- drivers/dma-buf/dma-resv.c | 104 +++++++++++++++++++++++++++++++++++++ include/linux/dma-resv.h | 2 + 2 files changed, 106 insertions(+) diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 6ddbeb5dfbf65..5dd4c38bd9cb4 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -33,6 +33,8 @@ */ #include +#include +#include #include #include #include @@ -49,6 +51,19 @@ * write-side updates. */ +/** + * dma_fence_deep_dive_for_each - deep dive into the fence containers + * @fence: resulting fence + * @chain: variable for a dma_fence_chain + * @index: index into a dma_fence_array + * @head: starting point + * + * Helper to deep dive into the fence containers for flattening them. + */ +#define dma_fence_deep_dive_for_each(fence, chain, index, head) \ + dma_fence_chain_for_each(chain, head) \ + dma_fence_array_for_each(fence, index, chain) + DEFINE_WD_CLASS(reservation_ww_class); EXPORT_SYMBOL(reservation_ww_class); @@ -517,6 +532,95 @@ int dma_resv_get_fences_rcu(struct dma_resv *obj, } EXPORT_SYMBOL_GPL(dma_resv_get_fences_rcu); +/** + * dma_resv_get_singleton - get a single fence for the dma_resv object + * @obj: the reservation object + * @extra: extra fence to add to the resulting array + * @result: resulting dma_fence + * + * Get a single fence representing all unsignaled fences in the dma_resv object + * plus the given extra fence. If we got only one fence return a new + * reference to that, otherwise return a dma_fence_array object. + * + * RETURNS + * Returns -NOMEM if allocations fail, zero otherwise. + */ +int dma_resv_get_singleton_rcu(struct dma_resv *obj, struct dma_fence **result) +{ + struct dma_fence **resv_fences, *fence, *chain, **fences; + struct dma_fence_array *array; + unsigned int num_resv_fences, num_fences; + unsigned int ret, i, j; + + ret = dma_resv_get_fences_rcu(obj, NULL, &num_resv_fences, &resv_fences); + if (ret) + return ret; + + num_fences = 0; + *result = NULL; + + if (num_resv_fences == 0) + return 0; + + for (i = 0; i < num_resv_fences; ++i) { + dma_fence_deep_dive_for_each(fence, chain, j, resv_fences[i]) { + if (dma_fence_is_signaled(fence)) + continue; + + *result = fence; + ++num_fences; + } + } + + if (num_fences <= 1) { + *result = dma_fence_get(*result); + goto put_resv_fences; + } + + fences = kmalloc_array(num_fences, sizeof(struct dma_fence*), + GFP_KERNEL); + if (!fences) { + *result = NULL; + ret = -ENOMEM; + goto put_resv_fences; + } + + num_fences = 0; + for (i = 0; i < num_resv_fences; ++i) { + dma_fence_deep_dive_for_each(fence, chain, j, resv_fences[i]) { + if (!dma_fence_is_signaled(fence)) + fences[num_fences++] = dma_fence_get(fence); + } + } + + if (num_fences <= 1) { + *result = num_fences ? fences[0] : NULL; + kfree(fences); + goto put_resv_fences; + } + + array = dma_fence_array_create(num_fences, fences, + dma_fence_context_alloc(1), + 1, false); + if (array) { + *result = &array->base; + } else { + *result = NULL; + while (num_fences--) + dma_fence_put(fences[num_fences]); + kfree(fences); + ret = -ENOMEM; + } + +put_resv_fences: + while (num_resv_fences--) + dma_fence_put(resv_fences[num_resv_fences]); + kfree(resv_fences); + + return ret; +} +EXPORT_SYMBOL_GPL(dma_resv_get_singleton_rcu); + /** * dma_resv_wait_timeout_rcu - Wait on reservation's objects * shared and/or exclusive fences. diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index d44a77e8a7e34..5f82894fed0b9 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -285,6 +285,8 @@ int dma_resv_get_fences_rcu(struct dma_resv *obj, int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src); +int dma_resv_get_singleton_rcu(struct dma_resv *obj, struct dma_fence **result); + long dma_resv_wait_timeout_rcu(struct dma_resv *obj, bool wait_all, bool intr, unsigned long timeout); From patchwork Wed Mar 17 22:19:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12147055 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 BDBF4C433DB for ; Wed, 17 Mar 2021 22:19:58 +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 52D9764F20 for ; Wed, 17 Mar 2021 22:19:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 52D9764F20 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=jlekstrand.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A93896E048; Wed, 17 Mar 2021 22:19:52 +0000 (UTC) Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 254AF6E047 for ; Wed, 17 Mar 2021 22:19:52 +0000 (UTC) Received: by mail-pj1-x102d.google.com with SMTP id x7-20020a17090a2b07b02900c0ea793940so3986135pjc.2 for ; Wed, 17 Mar 2021 15:19:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlekstrand-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=iwByVHb69StVBAc9q0H7wmWfj7jSk5zujRYrb4s7sBw=; b=Loc85C239HZzEeJ24Cnsrh3o9cROJPYJq/sTr+CAjznW9bLutx99kDSU5MGFDR+nNJ OhJ6HTOVEwSvibvCKdEXJnz+tTZQqNBLuyj3BenrX8ZfORr/jUrcikq9YILtNyzlSvVR j+xAHx5V60m0LJrpeK9JuZBccDK5qinj9w+dR279IE4o4G0dX3+WmaG1OnqbtA4Ty9Hq vMMlWkypaJyx0/Q+PwPdQSOB5GlAjnSjHhWvf3tUPc96CpGlGnb83arKL+3SFKTtXQ31 ICmJ9ujOx27uPWNzkAzMfgd6DiIviftWyjIHp2oOdKdsdlIRmjrZ8iGVEb8z6ZWX1MCR jVLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=iwByVHb69StVBAc9q0H7wmWfj7jSk5zujRYrb4s7sBw=; b=SfiRk4daAyUa2htkAQsbDDbG3c/Khha2cgQfmqjQHlvGq9NvFtFkn1AgsFlF1/In12 3fNhcat6dKZtDmnC4KsnDSvvxtqUv5vGHQPltBAhCiL4Czcy2MB7IKxTclXmfi3XnUOe J8vytxv24901uYdW8WgsCrRlB1XTpNbkV91FXJCojJ3MeOhDGs2J33reeY4njTb2e1ia NrerELwNrUKQluD7M+JrrqHvsji+tth3+bxbxq0h7M7VSn7NYVrCojMepxmI4f1N154M x3qNEo0Bf5Y59Rfk8jYQUyoCiypaWFStWPkyxF+f7MBt2YrOqhxLLv/RVTfKZBLhJz+i jhVg== X-Gm-Message-State: AOAM5333qgBPiRYfgHsIH+ySwy38ylmNzRE+wsBD7u6nF8eAy6fN9VjX NM3QCH/yObENs3JBYRalebewPGKmDRk1vg== X-Google-Smtp-Source: ABdhPJw7oyNTfh1fvln9xFuyWQ0IOsLRUzXAZXxaOF6tEKg4vv1+HFOkexmXhicMWVgki03MaH4amw== X-Received: by 2002:a17:902:8482:b029:e6:325b:5542 with SMTP id c2-20020a1709028482b02900e6325b5542mr6528578plo.70.1616019591183; Wed, 17 Mar 2021 15:19:51 -0700 (PDT) Received: from omlet.lan (jfdmzpr05-ext.jf.intel.com. [134.134.139.74]) by smtp.gmail.com with ESMTPSA id l19sm117708pjt.16.2021.03.17.15.19.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Mar 2021 15:19:50 -0700 (PDT) From: Jason Ekstrand To: dri-devel@lists.freedesktop.org Subject: [PATCH 3/3] dma-buf: Add an API for exporting sync files (v8) Date: Wed, 17 Mar 2021 17:19:40 -0500 Message-Id: <20210317221940.2146688-4-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210317221940.2146688-1-jason@jlekstrand.net> References: <20210316045322.2020294-1-jason@jlekstrand.net> <20210317221940.2146688-1-jason@jlekstrand.net> MIME-Version: 1.0 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: , Cc: Jason Ekstrand Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Modern userspace APIs like Vulkan are built on an explicit synchronization model. This doesn't always play nicely with the implicit synchronization used in the kernel and assumed by X11 and Wayland. The client -> compositor half of the synchronization isn't too bad, at least on intel, because we can control whether or not i915 synchronizes on the buffer and whether or not it's considered written. The harder part is the compositor -> client synchronization when we get the buffer back from the compositor. We're required to be able to provide the client with a VkSemaphore and VkFence representing the point in time where the window system (compositor and/or display) finished using the buffer. With current APIs, it's very hard to do this in such a way that we don't get confused by the Vulkan driver's access of the buffer. In particular, once we tell the kernel that we're rendering to the buffer again, any CPU waits on the buffer or GPU dependencies will wait on some of the client rendering and not just the compositor. This new IOCTL solves this problem by allowing us to get a snapshot of the implicit synchronization state of a given dma-buf in the form of a sync file. It's effectively the same as a poll() or I915_GEM_WAIT only, instead of CPU waiting directly, it encapsulates the wait operation, at the current moment in time, in a sync_file so we can check/wait on it later. As long as the Vulkan driver does the sync_file export from the dma-buf before we re-introduce it for rendering, it will only contain fences from the compositor or display. This allows to accurately turn it into a VkFence or VkSemaphore without any over- synchronization. v2 (Jason Ekstrand): - Use a wrapper dma_fence_array of all fences including the new one when importing an exclusive fence. v3 (Jason Ekstrand): - Lock around setting shared fences as well as exclusive - Mark SIGNAL_SYNC_FILE as a read-write ioctl. - Initialize ret to 0 in dma_buf_wait_sync_file v4 (Jason Ekstrand): - Use the new dma_resv_get_singleton helper v5 (Jason Ekstrand): - Rename the IOCTLs to import/export rather than wait/signal - Drop the WRITE flag and always get/set the exclusive fence v6 (Jason Ekstrand): - Drop the sync_file import as it was all-around sketchy and not nearly as useful as import. - Re-introduce READ/WRITE flag support for export - Rework the commit message v7 (Jason Ekstrand): - Require at least one sync flag - Fix a refcounting bug: dma_resv_get_excl() doesn't take a reference - Use _rcu helpers since we're accessing the dma_resv read-only v8 (Jason Ekstrand): - Return -ENOMEM if the sync_file_create fails - Predicate support on IS_ENABLED(CONFIG_SYNC_FILE) Signed-off-by: Jason Ekstrand Acked-by: Simon Ser --- drivers/dma-buf/dma-buf.c | 62 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/dma-buf.h | 6 ++++ 2 files changed, 68 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index f264b70c383eb..a5e4b0b6a049c 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -362,6 +363,62 @@ static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf) return ret; } +#if IS_ENABLED(CONFIG_SYNC_FILE) +static long dma_buf_export_sync_file(struct dma_buf *dmabuf, + void __user *user_data) +{ + struct dma_buf_sync_file arg; + struct dma_fence *fence = NULL; + struct sync_file *sync_file; + int fd, ret; + + if (copy_from_user(&arg, user_data, sizeof(arg))) + return -EFAULT; + + if (arg.flags & ~DMA_BUF_SYNC_RW) + return -EINVAL; + + if ((arg.flags & DMA_BUF_SYNC_RW) == 0) + return -EINVAL; + + fd = get_unused_fd_flags(O_CLOEXEC); + if (fd < 0) + return fd; + + if (arg.flags & DMA_BUF_SYNC_WRITE) { + ret = dma_resv_get_singleton_rcu(dmabuf->resv, &fence); + if (ret) + goto err_put_fd; + } else if (arg.flags & DMA_BUF_SYNC_READ) { + fence = dma_resv_get_excl_rcu(dmabuf->resv); + } + + if (!fence) + fence = dma_fence_get_stub(); + + sync_file = sync_file_create(fence); + + dma_fence_put(fence); + + if (!sync_file) { + ret = -ENOMEM; + goto err_put_fd; + } + + fd_install(fd, sync_file->file); + + arg.fd = fd; + if (copy_to_user(user_data, &arg, sizeof(arg))) + return -EFAULT; + + return 0; + +err_put_fd: + put_unused_fd(fd); + return ret; +} +#endif + static long dma_buf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -405,6 +462,11 @@ static long dma_buf_ioctl(struct file *file, case DMA_BUF_SET_NAME_B: return dma_buf_set_name(dmabuf, (const char __user *)arg); +#if IS_ENABLED(CONFIG_SYNC_FILE) + case DMA_BUF_IOCTL_EXPORT_SYNC_FILE: + return dma_buf_export_sync_file(dmabuf, (void __user *)arg); +#endif + default: return -ENOTTY; } diff --git a/include/uapi/linux/dma-buf.h b/include/uapi/linux/dma-buf.h index 7f30393b92c3b..9bce1e8bd31d3 100644 --- a/include/uapi/linux/dma-buf.h +++ b/include/uapi/linux/dma-buf.h @@ -37,6 +37,11 @@ struct dma_buf_sync { #define DMA_BUF_NAME_LEN 32 +struct dma_buf_sync_file { + __u32 flags; + __s32 fd; +}; + #define DMA_BUF_BASE 'b' #define DMA_BUF_IOCTL_SYNC _IOW(DMA_BUF_BASE, 0, struct dma_buf_sync) @@ -46,5 +51,6 @@ struct dma_buf_sync { #define DMA_BUF_SET_NAME _IOW(DMA_BUF_BASE, 1, const char *) #define DMA_BUF_SET_NAME_A _IOW(DMA_BUF_BASE, 1, u32) #define DMA_BUF_SET_NAME_B _IOW(DMA_BUF_BASE, 1, u64) +#define DMA_BUF_IOCTL_EXPORT_SYNC_FILE _IOWR(DMA_BUF_BASE, 2, struct dma_buf_sync_file) #endif