From patchwork Tue Mar 16 04:53:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12141245 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,URIBL_BLOCKED,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 776E5C433E0 for ; Tue, 16 Mar 2021 05:00:49 +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 D8DB7650BB for ; Tue, 16 Mar 2021 05:00:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8DB7650BB 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 4F3B489C8D; Tue, 16 Mar 2021 05:00:48 +0000 (UTC) Received: from mail-oi1-x22f.google.com (mail-oi1-x22f.google.com [IPv6:2607:f8b0:4864:20::22f]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9FA7C89C8D for ; Tue, 16 Mar 2021 05:00:46 +0000 (UTC) Received: by mail-oi1-x22f.google.com with SMTP id d20so36884178oiw.10 for ; Mon, 15 Mar 2021 22:00:46 -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=V7TndwpQhu+oiUPhkn0Az9On9YRq3u1BtO+zfx+aRFBBV8KyGKuib0eBcYRDvBs+fL COtzlufkp9SXSfq2DQ+IcesezUhNBly0PM4skxsH3S/xl8/La5XzWlZOrWLsxno3+bAV D0Ykj7QqTNTfN6ByUkfgKkbvD/IhR7jpMBUY8v/mgCCzqOAzE9ktQOugaCWXLMLgPAcT Jsi7Bsc31niKZnjDg5OL4+LtgF2n7ENwcmQhQe7kHSZHSx+tPEsoK4NvDGobTANsS7Ff L5GnyVf+m1zX7smeT5PDJJxD9TUTzhGN8pKe9MJsLLmG5K/u5+xLZLB1uKNAiHCODRx9 lfAA== 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=MhirwkjhF+7Rv4KkRMmM9ZC6aj+ZPxjbkLof1gmlP+C5XMds6N24zpoQ67mxxc95x2 76wDPLN98zryY/ckOmiAzY8zGwt1Z7yIPCDDcaiTRm92A8wDeHZGGVc3SGpw+rSUoVYw 1quPfiOm/k/FZx9lbVcV4Rh2ePaFtNhHqGVyKa5DH79NOxnIStG5YjVoTIGcGuNr6z9v YlE167uovGuawAobIHDAVpCMXFZ9FdNc0JCJmztB4q1Aw3txxsM2XOqUoYe+Qmh/6UdC mijIAk0z9qg46UY6YkzycYdAJ0gXT/k4zWIs1OUBigo/bfExgc0B3zhcn5fZgopxmHnt BM8g== X-Gm-Message-State: AOAM531msV6WbKnpl7n/PeXz/OAYvwdl4bwlrQtK8dTtjfGbPXxu2Z4D iHt3nsHa8jBYGSCrXYOxHxHjpzon6evsdg== X-Google-Smtp-Source: ABdhPJyzSSb9XXLuLbFJQFF44nOWoa2E8vzSjK7UwQDKfK6Q6JbS/iQ+lo85eRTbt0+GaNq5SFv60g== X-Received: by 2002:a17:90a:c909:: with SMTP id v9mr2911617pjt.218.1615870409888; Mon, 15 Mar 2021 21:53:29 -0700 (PDT) Received: from omlet.com (jfdmzpr04-ext.jf.intel.com. [134.134.137.73]) by smtp.gmail.com with ESMTPSA id w128sm15147785pfw.86.2021.03.15.21.53.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Mar 2021 21:53:29 -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: Mon, 15 Mar 2021 23:53:20 -0500 Message-Id: <20210316045322.2020294-2-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210316045322.2020294-1-jason@jlekstrand.net> References: <20210315210453.1667925-1-jason@jlekstrand.net> <20210316045322.2020294-1-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 Tue Mar 16 04:53:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12141251 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,URIBL_BLOCKED,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 4E8AFC433DB for ; Tue, 16 Mar 2021 05:02:43 +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 03FB665138 for ; Tue, 16 Mar 2021 05:02:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03FB665138 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 7643489CD4; Tue, 16 Mar 2021 05:02:42 +0000 (UTC) Received: from mail-pf1-x436.google.com (mail-pf1-x436.google.com [IPv6:2607:f8b0:4864:20::436]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8AC0589CD4 for ; Tue, 16 Mar 2021 05:02:41 +0000 (UTC) Received: by mail-pf1-x436.google.com with SMTP id x21so6700749pfa.3 for ; Mon, 15 Mar 2021 22:02:41 -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=tkQwS9mWhJ+JqGdsxXlRx16hbu2zbQEB+vyLzv1fnXhbHRRmybJ0FtY7ml09Gz6uKX 4hT0yni+Ll9P7UdACJSg4HBcnFmJ6rEldSpDnmQofeetBszR+zB3rTTG4OqY8s9CjWg3 LldVcV+JXKi9T1Jex5ToOMfGkqNGcJX5Oe4Lro7civB7Kt1Z3MExXnYRKLbQREO4pghl vGT2+kXNbENGh22Csnr31zCRcv52kTI7V8jInuljDG8hWq9x5JBgV3uKCESkQ4Kp2L0b /jaScYddC1WkltMO+W+Mxjq4xpb+EzVlCiW7iavLs8/t62fQ6UDW/nCXi93ncyWDOHjv OOMw== 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=SWb2Ukz/QiU7G/ssMUH4j/C7IKJ6JtUihsWoo/+E5k6xhIyDM5ekLNspp//VAY2GGy fY0iWqyo7vz6Ncr7+v/kCoISJOzyQyS0Fkp00SY5VBX4i0am9KJ+PajNkqjjxWurKQJS R5FggH06gDjwG6X7P/hmgKvyHukT2bWa9rS2e2/mDP6CducD+ottzllcUR9uSVU6dbec pgG3qIMoUkpKFmds+ER8uWEKaxBTBQc47DKD99T8+JPAMtgGPAJqDa196+uhclax58ak dj7uzWaHQqDBjaLbClpVDoL7w0Ua1FYCC7427UzhvhN+oQn/ji/2NwJQm7I60POLPxiy XD5w== X-Gm-Message-State: AOAM531CbxDwDO1y+VtZ0I+43+VIQ0dFsBJMdT7g48EDl7jWma8hJNzx 3ebQQM6oV5ndYCqv7AiNKj3lrn+LLkdYvQ== X-Google-Smtp-Source: ABdhPJxZ4fAt0tglHnBVceTE6VTtfmNzcnXJXPLm0jByOYLmF171jgnR0DlKhFrhkN0NU4qhVf6ncQ== X-Received: by 2002:a65:5a0a:: with SMTP id y10mr2240867pgs.122.1615870411236; Mon, 15 Mar 2021 21:53:31 -0700 (PDT) Received: from omlet.com (jfdmzpr04-ext.jf.intel.com. [134.134.137.73]) by smtp.gmail.com with ESMTPSA id w128sm15147785pfw.86.2021.03.15.21.53.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Mar 2021 21:53:30 -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: Mon, 15 Mar 2021 23:53:21 -0500 Message-Id: <20210316045322.2020294-3-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210316045322.2020294-1-jason@jlekstrand.net> References: <20210315210453.1667925-1-jason@jlekstrand.net> <20210316045322.2020294-1-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 Tue Mar 16 04:53:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12141249 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,URIBL_BLOCKED,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 45639C433E0 for ; Tue, 16 Mar 2021 05:01:39 +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 F26BC65137 for ; Tue, 16 Mar 2021 05:01:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F26BC65137 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 8226E6E1F5; Tue, 16 Mar 2021 05:01:38 +0000 (UTC) Received: from mail-il1-x132.google.com (mail-il1-x132.google.com [IPv6:2607:f8b0:4864:20::132]) by gabe.freedesktop.org (Postfix) with ESMTPS id A9DCE6E1F5 for ; Tue, 16 Mar 2021 05:01:37 +0000 (UTC) Received: by mail-il1-x132.google.com with SMTP id z9so11562354iln.1 for ; Mon, 15 Mar 2021 22:01:37 -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=074iEiZZhKRUAMbXMplvFHK8p3PMtccyfos3PpqzgSQ=; b=JskXgfao01yeqFoAau01czUE504gmlXn+ZlCSzxKzajWkGgxhu9MfqnvUFGX0ELMNQ WIDYk8FREfhHUYD1H1RVXF9nRXu9jsevD9InS9PTjch03bAHRAAjsziZo2CGcxtN5boh uNu9rVLCh7Q/xSl5i2SGrDOh2kxmAixDy+5Va4SFfTM5St1mybqF3BSK/AZFoWSkPEXz lIcwwCI4w2aFRDr/7e7vQ4z9UXwY/Qj/1/BxnPfvuENS4pTs/6FwXwGTHVj8s2/fPQQh /WLv5pDnzqeFNBpToxIr/XOCOi05pk+9XoExKE1Pux2dcOAfpBQov4gnRDu2IqwIkXiS VxRA== 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=074iEiZZhKRUAMbXMplvFHK8p3PMtccyfos3PpqzgSQ=; b=nVRi/48pT30a2kdBvABPCDEbnFFLz8CG1bngWdhyJECIII2GfFovdM2SV8b+GxENfh 6FMEDXOJKL2auPGUVik4zgwCy6ywP/JAhRW8cO3k6q2zLgxlcqZJBBAx6tB7TpFtltCa aX5UOb7+EvFuf3qMc9FnsYMwp0kIdShsDBqttRcROd3TwyJgV2YdMucxVZW3SEmNRPkF qLOrBRnWYvc/+0Ef2dUKE4/WMQnYEI2Iu3uKr3BmVVsuQ0EzbFxyu9xCaUtz+yfeX5h9 YDtrEzux0k4lIZVdH6Qi8atqhnqEyPxbrUZ9Yi0SB6XIW6JHkwQeD3ppCk4EA7ptx8Lj 10oQ== X-Gm-Message-State: AOAM532VLeofdlMiZlO4Nv2rKjOUaM2SEb7I8/TLtS19inOudY2jfuDA 8/zahbq/09PRqzIQ8dY4mc37RqH8FgPzgg== X-Google-Smtp-Source: ABdhPJypW6vJltLP8xEen1ngwqRXtv0/bxLpS8RmvOISuHhFQO6OCgMDQgOQIsMChOdhSEHz800BGA== X-Received: by 2002:a63:d618:: with SMTP id q24mr2201565pgg.283.1615870412753; Mon, 15 Mar 2021 21:53:32 -0700 (PDT) Received: from omlet.com (jfdmzpr04-ext.jf.intel.com. [134.134.137.73]) by smtp.gmail.com with ESMTPSA id w128sm15147785pfw.86.2021.03.15.21.53.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Mar 2021 21:53:32 -0700 (PDT) From: Jason Ekstrand To: dri-devel@lists.freedesktop.org Subject: [PATCH 3/3] dma-buf: Add an API for exporting sync files (v7) Date: Mon, 15 Mar 2021 23:53:22 -0500 Message-Id: <20210316045322.2020294-4-jason@jlekstrand.net> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210316045322.2020294-1-jason@jlekstrand.net> References: <20210315210453.1667925-1-jason@jlekstrand.net> <20210316045322.2020294-1-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 Signed-off-by: Jason Ekstrand Reported-by: kernel test robot --- drivers/dma-buf/dma-buf.c | 58 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/dma-buf.h | 6 ++++ 2 files changed, 64 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index f264b70c383eb..69200d019ac90 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 +363,60 @@ static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf) return ret; } +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 = -EINVAL; + 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; +} + static long dma_buf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -405,6 +460,9 @@ static long dma_buf_ioctl(struct file *file, case DMA_BUF_SET_NAME_B: return dma_buf_set_name(dmabuf, (const char __user *)arg); + case DMA_BUF_IOCTL_EXPORT_SYNC_FILE: + return dma_buf_export_sync_file(dmabuf, (void __user *)arg); + 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