From patchwork Tue Nov 17 19:18:01 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Walter X-Patchwork-Id: 545740 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2001:1868:205::9]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 13A9E141448 for ; Wed, 18 Nov 2015 06:20:25 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zyllw-0007Vg-Te; Tue, 17 Nov 2015 19:18:32 +0000 Received: from mail.sigma-star.at ([95.130.255.111]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zyllt-0007Ja-KA for linux-mtd@lists.infradead.org; Tue, 17 Nov 2015 19:18:31 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.sigma-star.at (Postfix) with ESMTP id B7E6924E0002 for ; Tue, 17 Nov 2015 20:18:07 +0100 (CET) X-Virus-Scanned: amavisd-new at mail.sigma-star.at Received: from dw-book (80-110-107-146.cgn.dynamic.surfer.at [80.110.107.146]) by mail.sigma-star.at (Postfix) with ESMTPSA id 3A1ED24E0001 for ; Tue, 17 Nov 2015 20:18:06 +0100 (CET) Received: by dw-book (sSMTP sendmail emulation); Tue, 17 Nov 2015 20:18:01 +0100 Date: Tue, 17 Nov 2015 20:18:01 +0100 From: Daniel Walter To: linux-mtd@lists.infradead.org Subject: [RFC] [PATCH] mtd: add tracepoints for mtd_read and mtd_write Message-ID: <20151117191801.GA864@dw-nb.local> References: <20151117191448.GA5367@dw-nb.local> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20151117191448.GA5367@dw-nb.local> User-Agent: Mutt/1.5.24 (2015-08-30) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151117_111830_091317_9CA37B76 X-CRM114-Status: GOOD ( 17.89 ) X-Spam-Score: -2.5 (--) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-2.5 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Add tracepoints to mtd subsystem for read and write operations. This should allow us to identify applications which are generating too much reads/writes on a flash-device. Signed-off-by: Daniel Walter --- drivers/mtd/mtdcore.c | 6 +++++- include/trace/events/mtd.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+), 1 deletion(-) create mode 100644 include/trace/events/mtd.h diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 8bbbb75..8f85bfb 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -43,6 +43,9 @@ #include #include +#define CREATE_TRACE_POINTS +#include + #include "mtdcore.h" static struct backing_dev_info mtd_bdi = { @@ -882,7 +885,7 @@ int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, return -EINVAL; if (!len) return 0; - + trace_mtd_read(current, len); /* * In the absence of an error, drivers return a non-negative integer * representing the maximum number of bitflips that were corrected on @@ -907,6 +910,7 @@ int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, return -EROFS; if (!len) return 0; + trace_mtd_write(current, len); return mtd->_write(mtd, to, len, retlen, buf); } EXPORT_SYMBOL_GPL(mtd_write); diff --git a/include/trace/events/mtd.h b/include/trace/events/mtd.h new file mode 100644 index 0000000..7191b72 --- /dev/null +++ b/include/trace/events/mtd.h @@ -0,0 +1,45 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM mtd + +#if !defined(_TRACE_MTD_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_MTD_H + +#include + +TRACE_EVENT(mtd_read, + TP_PROTO(struct task_struct *task, size_t rlen), + TP_ARGS(task, rlen), + TP_STRUCT__entry( + __field(pid_t, pid) + __array(char, comm, TASK_COMM_LEN) + __field(size_t, rlen) + ), + TP_fast_assign( + __entry->pid = task->pid; + memcpy(__entry->comm, task->comm, TASK_COMM_LEN); + __entry->rlen = rlen; + ), + TP_printk("pid=%d comm=%s rlen=%zu", + __entry->pid, __entry->comm, __entry->rlen) +); + +TRACE_EVENT(mtd_write, + TP_PROTO(struct task_struct *task, size_t wlen), + TP_ARGS(task, wlen), + TP_STRUCT__entry( + __field(pid_t, pid) + __array(char, comm, TASK_COMM_LEN) + __field(size_t, wlen) + ), + TP_fast_assign( + __entry->pid = task->pid; + memcpy(__entry->comm, task->comm, TASK_COMM_LEN); + __entry->wlen = wlen; + ), + TP_printk("pid=%d comm=%s wlen=%zu", + __entry->pid, __entry->comm, __entry->wlen) +); +#endif /* _TRACE_MTD_H */ + +/* This part must be outside protection */ +#include