From patchwork Thu Apr 25 02:21:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Xiang X-Patchwork-Id: 13642788 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 33507C10F15 for ; Thu, 25 Apr 2024 02:24:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rzol5-0000Xe-4R; Wed, 24 Apr 2024 22:22:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rzol0-0000WX-LW for qemu-devel@nongnu.org; Wed, 24 Apr 2024 22:22:42 -0400 Received: from out-181.mta1.migadu.com ([95.215.58.181]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rzoky-0005AI-GN for qemu-devel@nongnu.org; Wed, 24 Apr 2024 22:22:42 -0400 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1714011759; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EGc89WKM0cHq+3UC0v4DbA0/xNOJoDXKucErcy0uuiY=; b=N6xoF3F73kIv8H/hfvV+egYoZEo1tfaV8qqLMD+9H6mCii5OPPwfx8xxJO6Eyw9LXvZhAp ZYuGHT3ldLI1KPWPTJFG8DjpBTDfGSXTJvz9xzCfBjwbvSbNthSgOcWgUCB64W5fYLnCvI EL+aDTysNY2Qy71hSNoHAMJc7ZX6D0Y= From: Hao Xiang To: marcandre.lureau@redhat.com, peterx@redhat.com, farosas@suse.de, armbru@redhat.com, lvivier@redhat.com, qemu-devel@nongnu.org Cc: Hao Xiang , Bryan Zhang Subject: [PATCH v4 07/14] util/dsa: Implement DSA task asynchronous submission and wait for completion. Date: Thu, 25 Apr 2024 02:21:10 +0000 Message-Id: <20240425022117.4035031-8-hao.xiang@linux.dev> In-Reply-To: <20240425022117.4035031-1-hao.xiang@linux.dev> References: <20240425022117.4035031-1-hao.xiang@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Received-SPF: pass client-ip=95.215.58.181; envelope-from=hao.xiang@linux.dev; helo=out-181.mta1.migadu.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org * Add a DSA task completion callback. * DSA completion thread will call the tasks's completion callback on every task/batch task completion. * DSA submission path to wait for completion. * Implement CPU fallback if DSA is not able to complete the task. Signed-off-by: Hao Xiang Signed-off-by: Bryan Zhang --- include/qemu/dsa.h | 14 +++++ util/dsa.c | 147 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 158 insertions(+), 3 deletions(-) diff --git a/include/qemu/dsa.h b/include/qemu/dsa.h index 645e6fc367..e002652879 100644 --- a/include/qemu/dsa.h +++ b/include/qemu/dsa.h @@ -91,6 +91,20 @@ buffer_zero_batch_task_init(struct dsa_batch_task *task, */ void buffer_zero_batch_task_destroy(struct dsa_batch_task *task); +/** + * @brief Performs buffer zero comparison on a DSA batch task asynchronously. + * + * @param batch_task A pointer to the batch task. + * @param buf An array of memory buffers. + * @param count The number of buffers in the array. + * @param len The buffer length. + * + * @return Zero if successful, otherwise non-zero. + */ +int +buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, + const void **buf, size_t count, size_t len); + #else static inline bool dsa_is_running(void) diff --git a/util/dsa.c b/util/dsa.c index 9db4cfcf1d..5a2bf33651 100644 --- a/util/dsa.c +++ b/util/dsa.c @@ -473,6 +473,57 @@ poll_completion(struct dsa_completion_record *completion, return 0; } +/** + * @brief Helper function to use CPU to complete a single + * zero page checking task. + * + * @param completion A pointer to a DSA task completion record. + * @param descriptor A pointer to a DSA task descriptor. + * @param result A pointer to the result of a zero page checking. + */ +static void +task_cpu_fallback_int(struct dsa_completion_record *completion, + struct dsa_hw_desc *descriptor, bool *result) +{ + const uint8_t *buf; + size_t len; + + if (completion->status == DSA_COMP_SUCCESS) { + return; + } + + /* + * DSA was able to partially complete the operation. Check the + * result. If we already know this is not a zero page, we can + * return now. + */ + if (completion->bytes_completed != 0 && completion->result != 0) { + *result = false; + return; + } + + /* Let's fallback to use CPU to complete it. */ + buf = (const uint8_t *)descriptor->src_addr; + len = descriptor->xfer_size; + *result = buffer_is_zero(buf + completion->bytes_completed, + len - completion->bytes_completed); +} + +/** + * @brief Use CPU to complete a single zero page checking task. + * + * @param task A pointer to the task. + */ +static void +task_cpu_fallback(struct dsa_batch_task *task) +{ + assert(task->task_type == DSA_TASK); + + task_cpu_fallback_int(&task->completions[0], + &task->descriptors[0], + &task->results[0]); +} + /** * @brief Complete a single DSA task in the batch task. * @@ -574,6 +625,47 @@ exit: return ret; } +/** + * @brief Use CPU to complete the zero page checking batch task. + * + * @param batch_task A pointer to the batch task. + */ +static void +batch_task_cpu_fallback(struct dsa_batch_task *batch_task) +{ + assert(batch_task->task_type == DSA_BATCH_TASK); + + struct dsa_completion_record *batch_completion = + &batch_task->batch_completion; + struct dsa_completion_record *completion; + uint8_t status; + bool *results = batch_task->results; + uint32_t count = batch_task->batch_descriptor.desc_count; + + /* DSA is able to complete the entire batch task. */ + if (batch_completion->status == DSA_COMP_SUCCESS) { + assert(count == batch_completion->bytes_completed); + return; + } + + /* + * DSA encounters some error and is not able to complete + * the entire batch task. Use CPU fallback. + */ + for (int i = 0; i < count; i++) { + + completion = &batch_task->completions[i]; + status = completion->status; + + assert(status == DSA_COMP_SUCCESS || + status == DSA_COMP_PAGE_FAULT_NOBOF); + + task_cpu_fallback_int(completion, + &batch_task->descriptors[i], + &results[i]); + } +} + /** * @brief Handles an asynchronous DSA batch task completion. * @@ -861,7 +953,6 @@ buffer_zero_batch_task_set(struct dsa_batch_task *batch_task, * * @return int Zero if successful, otherwise an appropriate error code. */ -__attribute__((unused)) static int buffer_zero_dsa_async(struct dsa_batch_task *task, const void *buf, size_t len) @@ -880,7 +971,6 @@ buffer_zero_dsa_async(struct dsa_batch_task *task, * @param count The number of buffers. * @param len The buffer length. */ -__attribute__((unused)) static int buffer_zero_dsa_batch_async(struct dsa_batch_task *batch_task, const void **buf, size_t count, size_t len) @@ -911,13 +1001,29 @@ buffer_zero_dsa_completion(void *context) * * @param batch_task A pointer to the buffer zero comparison batch task. */ -__attribute__((unused)) static void buffer_zero_dsa_wait(struct dsa_batch_task *batch_task) { qemu_sem_wait(&batch_task->sem_task_complete); } +/** + * @brief Use CPU to complete the zero page checking task if DSA + * is not able to complete it. + * + * @param batch_task A pointer to the batch task. + */ +static void +buffer_zero_cpu_fallback(struct dsa_batch_task *batch_task) +{ + if (batch_task->task_type == DSA_TASK) { + task_cpu_fallback(batch_task); + } else { + assert(batch_task->task_type == DSA_BATCH_TASK); + batch_task_cpu_fallback(batch_task); + } +} + /** * @brief Check if DSA is running. * @@ -990,5 +1096,40 @@ void dsa_cleanup(void) dsa_device_group_cleanup(&dsa_group); } +/** + * @brief Performs buffer zero comparison on a DSA batch task asynchronously. + * + * @param batch_task A pointer to the batch task. + * @param buf An array of memory buffers. + * @param count The number of buffers in the array. + * @param len The buffer length. + * + * @return Zero if successful, otherwise non-zero. + */ +int +buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, + const void **buf, size_t count, size_t len) +{ + if (count <= 0 || count > batch_task->batch_size) { + return -1; + } + + assert(batch_task != NULL); + assert(len != 0); + assert(buf != NULL); + + if (count == 1) { + /* DSA doesn't take batch operation with only 1 task. */ + buffer_zero_dsa_async(batch_task, buf[0], len); + } else { + buffer_zero_dsa_batch_async(batch_task, buf, count, len); + } + + buffer_zero_dsa_wait(batch_task); + buffer_zero_cpu_fallback(batch_task); + + return 0; +} + #endif