From patchwork Fri Jun 28 14:55:36 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Brezillon X-Patchwork-Id: 13716284 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 53B77C30658 for ; Fri, 28 Jun 2024 14:55:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4AA9C10E509; Fri, 28 Jun 2024 14:55:41 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="WbvPFYZR"; dkim-atps=neutral Received: from madrid.collaboradmins.com (madrid.collaboradmins.com [46.235.227.194]) by gabe.freedesktop.org (Postfix) with ESMTPS id A978310E2FD for ; Fri, 28 Jun 2024 14:55:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1719586539; bh=DM/ExRsULnRBEi3akxLb4yY6w66qLJWjMpZ8YdfvSto=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WbvPFYZRJaK3M1ScecpKfiXTW6aD2D3Wz/EUPHJhEZcsPfro8tH8cJQXTLwIqPp4C qQ7xd5IvlzlQ2jnvwSOo4TIb9P/7JIZvb3td64CwMicvEqDnOADuy7f32YCWFpIFUz +o/+xMurr2g7uexHxGIHZ/wnXnKjLtSt6MOGPDQ1htzzhgTV6nSkiDWCh3/l8APv/l R3AAwvKrPYHemfLYPo61xnVkgvo7oA9SINxKDiVoK20piVJ7R0mpFI5sxSHgehbOXL cy/5tS5nlEuv3kqo6JN0CFP+lcPuHXjcGxUTKgsw64zKV9NCG5x8HoyhRBFnTSZ4uH rYIoVAHbJFPjg== Received: from localhost.localdomain (cola.collaboradmins.com [195.201.22.229]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by madrid.collaboradmins.com (Postfix) with ESMTPSA id 0629F37821FF; Fri, 28 Jun 2024 14:55:38 +0000 (UTC) From: Boris Brezillon To: Boris Brezillon , Steven Price , Liviu Dudau , =?utf-8?q?Adri=C3=A1n_Larumbe?= Cc: dri-devel@lists.freedesktop.org, kernel@collabora.com Subject: [PATCH 2/2] drm/panthor: Fix sync-only jobs Date: Fri, 28 Jun 2024 16:55:36 +0200 Message-ID: <20240628145536.778349-3-boris.brezillon@collabora.com> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20240628145536.778349-1-boris.brezillon@collabora.com> References: <20240628145536.778349-1-boris.brezillon@collabora.com> 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" A sync-only job is meant to provide a synchronization point on a queue, so we can't return a NULL fence there, we have to add a signal operation to the command stream which executes after all other previously submitted jobs are done. Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") Signed-off-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Steven Price --- drivers/gpu/drm/panthor/panthor_sched.c | 41 ++++++++++++++++++++----- include/uapi/drm/panthor_drm.h | 5 +++ 2 files changed, 38 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c index 79ffcbc41d78..951ff7e63ea8 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -458,6 +458,16 @@ struct panthor_queue { /** @seqno: Sequence number of the last initialized fence. */ atomic64_t seqno; + /** + * @last_fence: Fence of the last submitted job. + * + * We return this fence when we get an empty command stream. + * This way, we are guaranteed that all earlier jobs have completed + * when drm_sched_job::s_fence::finished without having to feed + * the CS ring buffer with a dummy job that only signals the fence. + */ + struct dma_fence *last_fence; + /** * @in_flight_jobs: List containing all in-flight jobs. * @@ -829,6 +839,9 @@ static void group_free_queue(struct panthor_group *group, struct panthor_queue * panthor_kernel_bo_destroy(queue->ringbuf); panthor_kernel_bo_destroy(queue->iface.mem); + /* Release the last_fence we were holding, if any. */ + dma_fence_put(queue->fence_ctx.last_fence); + kfree(queue); } @@ -2865,11 +2878,14 @@ queue_run_job(struct drm_sched_job *sched_job) static_assert(sizeof(call_instrs) % 64 == 0, "call_instrs is not aligned on a cacheline"); - /* Stream size is zero, nothing to do => return a NULL fence and let - * drm_sched signal the parent. + /* Stream size is zero, nothing to do except making sure all previously + * submitted jobs are done before we signal the + * drm_sched_job::s_fence::finished fence. */ - if (!job->call_info.size) - return NULL; + if (!job->call_info.size) { + job->done_fence = dma_fence_get(queue->fence_ctx.last_fence); + return job->done_fence; + } ret = pm_runtime_resume_and_get(ptdev->base.dev); if (drm_WARN_ON(&ptdev->base, ret)) @@ -2928,6 +2944,10 @@ queue_run_job(struct drm_sched_job *sched_job) } } + /* Update the last fence. */ + dma_fence_put(queue->fence_ctx.last_fence); + queue->fence_ctx.last_fence = dma_fence_get(job->done_fence); + done_fence = dma_fence_get(job->done_fence); out_unlock: @@ -3378,10 +3398,15 @@ panthor_job_create(struct panthor_file *pfile, goto err_put_job; } - job->done_fence = kzalloc(sizeof(*job->done_fence), GFP_KERNEL); - if (!job->done_fence) { - ret = -ENOMEM; - goto err_put_job; + /* Empty command streams don't need a fence, they'll pick the one from + * the previously submitted job. + */ + if (job->call_info.size) { + job->done_fence = kzalloc(sizeof(*job->done_fence), GFP_KERNEL); + if (!job->done_fence) { + ret = -ENOMEM; + goto err_put_job; + } } ret = drm_sched_job_init(&job->base, diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h index aaed8e12ad0b..926b1deb1116 100644 --- a/include/uapi/drm/panthor_drm.h +++ b/include/uapi/drm/panthor_drm.h @@ -802,6 +802,9 @@ struct drm_panthor_queue_submit { * Must be 64-bit/8-byte aligned (the size of a CS instruction) * * Can be zero if stream_addr is zero too. + * + * When the stream size is zero, the queue submit serves as a + * synchronization point. */ __u32 stream_size; @@ -822,6 +825,8 @@ struct drm_panthor_queue_submit { * ensure the GPU doesn't get garbage when reading the indirect command * stream buffers. If you want the cache flush to happen * unconditionally, pass a zero here. + * + * Ignored when stream_size is zero. */ __u32 latest_flush;