From patchwork Fri Oct 13 22:14:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Cavitt, Jonathan" X-Patchwork-Id: 13421794 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 B0472CDB47E for ; Fri, 13 Oct 2023 22:26:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E74F310E071; Fri, 13 Oct 2023 22:26:00 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id F25B310E072 for ; Fri, 13 Oct 2023 22:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697235958; x=1728771958; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tbYWLHj+eumaQcVVvUmFmGipHv5n+/lm2FOMQFJ9g+w=; b=falWha9gwbF0/9nwh4FZe1HHyUiZ0ctfwU8LJGVUgoG2DrBJHhP9ZMAG CgZlLy9GmMxb+m14w5VkYPKpY86mgP45jnUI74Y2c+WnQlJb+OUw1Ra7M MlgiqOR6yiPAr0rYLX4T32J7zHgCmQCTdAUKC0rU0pxFuV0X9C18az/oV mFm9iaqS3DlfJTJ48WPXgL91iZ6GchSEoe3Qf3bYku01K8qfk+Mpij63p PcbMraOBboLY/VumXm3yvsgtcLw/+X+MV3H4TiYgMZ/UnkGFPdbVB9MN5 njyfDvqMNRJ6ZstSGOXE6zvXOzJFSLNjKM+jn6Yj/39C6kduJfjTCJ/Cs w==; X-IronPort-AV: E=McAfee;i="6600,9927,10862"; a="385115678" X-IronPort-AV: E=Sophos;i="6.03,223,1694761200"; d="scan'208";a="385115678" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2023 15:25:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10862"; a="845641407" X-IronPort-AV: E=Sophos;i="6.03,223,1694761200"; d="scan'208";a="845641407" Received: from dut-internal-9dd7.jf.intel.com ([10.165.21.194]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2023 15:25:02 -0700 From: Jonathan Cavitt To: intel-gfx@lists.freedesktop.org Date: Fri, 13 Oct 2023 15:14:14 -0700 Message-Id: <20231013221419.2710833-3-jonathan.cavitt@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231013221419.2710833-1-jonathan.cavitt@intel.com> References: <20231013221419.2710833-1-jonathan.cavitt@intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v15 2/7] drm/i915/guc: Add CT size delay helper 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: , Cc: janusz.krzysztofik@intel.com, andi.shyti@intel.com, matthew.d.roper@intel.com, jonathan.cavitt@intel.com, saurabhg.gupta@intel.com, chris.p.wilson@linux.intel.com, nirmoy.das@intel.com Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" As of now, there is no mechanism for tracking a given request's progress through the queue. Instead, add a helper that returns an estimated maximum time the queue should take to drain if completely full. Suggested-by: John Harrison Signed-off-by: Jonathan Cavitt Reviewed-by: Andi Shyti Acked-by: Tvrtko Ursulin Reviewed-by: Nirmoy Das Reviewed-by: John Harrison --- drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 27 +++++++++++++++++++++++ drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h | 2 ++ 2 files changed, 29 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c index c33210ead1ef7..03b616ba4ebb7 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -103,6 +103,33 @@ enum { CTB_SEND = 0, CTB_RECV = 1 }; enum { CTB_OWNER_HOST = 0 }; +/* + * Some H2G commands involve a synchronous response that the driver needs + * to wait for. In such cases, a timeout is required to prevent the driver + * from waiting forever in the case of an error (either no error response + * is defined in the protocol or something has died and requires a reset). + * The specific command may be defined as having a time bound response but + * the CT is a queue and that time guarantee only starts from the point + * when the command reaches the head of the queue and is processed by GuC. + * + * Ideally there would be a helper to report the progress of a given + * command through the CT. However, that would require a significant + * amount of work in the CT layer. In the meantime, provide a reasonable + * estimation of the worst case latency it should take for the entire + * queue to drain. And therefore, how long a caller should wait before + * giving up on their request. The current estimate is based on empirical + * measurement of a test that fills the buffer with context creation and + * destruction requests as they seem to be the slowest operation. + */ +long intel_guc_ct_max_queue_time_jiffies(void) +{ + /* + * A 4KB buffer full of context destroy commands takes a little + * over a second to process so bump that to 2s to be super safe. + */ + return (CTB_H2G_BUFFER_SIZE * HZ) / SZ_2K; +} + static void ct_receive_tasklet_func(struct tasklet_struct *t); static void ct_incoming_request_worker_func(struct work_struct *w); diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h index 58e42901ff498..2c4bb9a941be6 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h @@ -104,6 +104,8 @@ struct intel_guc_ct { #endif }; +long intel_guc_ct_max_queue_time_jiffies(void); + void intel_guc_ct_init_early(struct intel_guc_ct *ct); int intel_guc_ct_init(struct intel_guc_ct *ct); void intel_guc_ct_fini(struct intel_guc_ct *ct);