From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 A68EBC43603 for ; Tue, 17 Dec 2019 13:43:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 839E4206B7 for ; Tue, 17 Dec 2019 13:43:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728501AbfLQNn6 (ORCPT ); Tue, 17 Dec 2019 08:43:58 -0500 Received: from foss.arm.com ([217.140.110.172]:37544 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726962AbfLQNn4 (ORCPT ); Tue, 17 Dec 2019 08:43:56 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 38A3231B; Tue, 17 Dec 2019 05:43:56 -0800 (PST) Received: from e123648.arm.com (unknown [10.37.12.145]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5B7003F719; Tue, 17 Dec 2019 05:43:54 -0800 (PST) From: lukasz.luba@arm.com To: linux-kernel@vger.kernel.org, sudeep.holla@arm.com, linux-arm-kernel@lists.infradead.org Cc: rostedt@goodmis.org, mingo@redhat.com, james.quinlan@broadcom.com, Lukasz Luba Subject: [PATCH v2 2/2] drivers: firmware: scmi: Extend SCMI transport layer by trace events Date: Tue, 17 Dec 2019 13:43:45 +0000 Message-Id: <20191217134345.14004-2-lukasz.luba@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191217134345.14004-1-lukasz.luba@arm.com> References: <20191217134345.14004-1-lukasz.luba@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lukasz Luba The SCMI transport layer communicates via mailboxes and shared memory with firmware running on a microcontroller. It is platform specific how long it takes to pass a SCMI message. The most sensitive requests are coming from CPUFreq subsystem, which might be used by the scheduler. Thus, there is a need to measure these delays and capture anomalies. This change introduces trace events wrapped around transfer code. According to Jim's suggestion a unique transfer_id is to distinguish similar entries which might have the same message id, protocol id and sequence. This is a case then there are some timeouts in transfers. Suggested-by: Jim Quinlan Signed-off-by: Lukasz Luba --- drivers/firmware/arm_scmi/common.h | 2 ++ drivers/firmware/arm_scmi/driver.c | 18 ++++++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 5237c2ff79fe..df35358ff324 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -81,6 +81,7 @@ struct scmi_msg { /** * struct scmi_xfer - Structure representing a message flow * + * @transfer_id: Unique ID for debug & profiling purpose * @hdr: Transmit message header * @tx: Transmit message * @rx: Receive message, the buffer should be pre-allocated to store @@ -90,6 +91,7 @@ struct scmi_msg { * @async: pointer to delayed response message received event completion */ struct scmi_xfer { + int transfer_id; struct scmi_msg_hdr hdr; struct scmi_msg tx; struct scmi_msg rx; diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 3eb0382491ce..15c5629ad2cd 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -29,6 +29,9 @@ #include "common.h" +#define CREATE_TRACE_POINTS +#include + #define MSG_ID_MASK GENMASK(7, 0) #define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) #define MSG_TYPE_MASK GENMASK(9, 8) @@ -61,6 +64,8 @@ enum scmi_error_codes { static LIST_HEAD(scmi_list); /* Protection for the entire list */ static DEFINE_MUTEX(scmi_list_mutex); +/* Track the unique id for the transfers for debug & profiling purpose */ +static atomic_t transfer_last_id; /** * struct scmi_xfers_info - Structure to manage transfer information @@ -304,6 +309,7 @@ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, xfer = &minfo->xfer_block[xfer_id]; xfer->hdr.seq = xfer_id; reinit_completion(&xfer->done); + xfer->transfer_id = atomic_inc_return(&transfer_last_id); return xfer; } @@ -374,6 +380,10 @@ static void scmi_rx_callback(struct mbox_client *cl, void *m) scmi_fetch_response(xfer, mem); + trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + msg_type); + if (msg_type == MSG_TYPE_DELAYED_RESP) complete(xfer->async_done); else @@ -439,6 +449,10 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) if (unlikely(!cinfo)) return -EINVAL; + trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + xfer->hdr.poll_completion); + ret = mbox_send_message(cinfo->chan, xfer); if (ret < 0) { dev_dbg(dev, "mbox send fail %d\n", ret); @@ -478,6 +492,10 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) */ mbox_client_txdone(cinfo->chan, ret); + trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + xfer->hdr.status); + return ret; } -- 2.17.1