From patchwork Thu Oct 14 02:03:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rongwei Wang X-Patchwork-Id: 12557667 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08DF4C433F5 for ; Thu, 14 Oct 2021 02:03:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7D65761154 for ; Thu, 14 Oct 2021 02:03:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7D65761154 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id E0DCC6B0078; Wed, 13 Oct 2021 22:03:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DBDE06B007B; Wed, 13 Oct 2021 22:03:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CACC46B007D; Wed, 13 Oct 2021 22:03:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id B75D66B0078 for ; Wed, 13 Oct 2021 22:03:40 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 583233015E for ; Thu, 14 Oct 2021 02:03:40 +0000 (UTC) X-FDA: 78693396600.26.514542A Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) by imf25.hostedemail.com (Postfix) with ESMTP id A47E9B00008E for ; Thu, 14 Oct 2021 02:03:37 +0000 (UTC) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R951e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=rongwei.wang@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0UrjbVWe_1634177013; Received: from localhost.localdomain(mailfrom:rongwei.wang@linux.alibaba.com fp:SMTPD_---0UrjbVWe_1634177013) by smtp.aliyun-inc.com(127.0.0.1); Thu, 14 Oct 2021 10:03:34 +0800 From: Rongwei Wang To: sj@kernel.org, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v2] mm/damon/dbgfs: remove unnecessary variables Date: Thu, 14 Oct 2021 10:03:33 +0800 Message-Id: <20211014020333.10330-1-rongwei.wang@linux.alibaba.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: A47E9B00008E X-Stat-Signature: hm956dtnxbw8wts4qa1et67i763reoie Authentication-Results: imf25.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf25.hostedemail.com: domain of rongwei.wang@linux.alibaba.com designates 115.124.30.133 as permitted sender) smtp.mailfrom=rongwei.wang@linux.alibaba.com X-HE-Tag: 1634177017-111270 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: In some functions, it's unnecessary to declare 'err' and 'ret' variables at the same time. This patch mainly to simplify the issue of such declarations by reusing one variable. Signed-off-by: Rongwei Wang --- mm/damon/dbgfs.c | 66 +++++++++++++++++++++++------------------------- 1 file changed, 31 insertions(+), 35 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 28d6abf27763..5cd4932800df 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -69,8 +69,7 @@ static ssize_t dbgfs_attrs_write(struct file *file, struct damon_ctx *ctx = file->private_data; unsigned long s, a, r, minr, maxr; char *kbuf; - ssize_t ret = count; - int err; + ssize_t ret; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) @@ -88,9 +87,9 @@ static ssize_t dbgfs_attrs_write(struct file *file, goto unlock_out; } - err = damon_set_attrs(ctx, s, a, r, minr, maxr); - if (err) - ret = err; + ret = damon_set_attrs(ctx, s, a, r, minr, maxr); + if (!ret) + ret = count; unlock_out: mutex_unlock(&ctx->kdamond_lock); out: @@ -220,14 +219,13 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf, struct damon_ctx *ctx = file->private_data; char *kbuf; struct damos **schemes; - ssize_t nr_schemes = 0, ret = count; - int err; + ssize_t nr_schemes = 0, ret; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) return PTR_ERR(kbuf); - schemes = str_to_schemes(kbuf, ret, &nr_schemes); + schemes = str_to_schemes(kbuf, count, &nr_schemes); if (!schemes) { ret = -EINVAL; goto out; @@ -239,11 +237,12 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf, goto unlock_out; } - err = damon_set_schemes(ctx, schemes, nr_schemes); - if (err) - ret = err; - else + ret = damon_set_schemes(ctx, schemes, nr_schemes); + if (!ret) { + ret = count; nr_schemes = 0; + } + unlock_out: mutex_unlock(&ctx->kdamond_lock); free_schemes_arr(schemes, nr_schemes); @@ -342,9 +341,8 @@ static ssize_t dbgfs_target_ids_write(struct file *file, char *kbuf, *nrs; unsigned long *targets; ssize_t nr_targets; - ssize_t ret = count; + ssize_t ret; int i; - int err; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) @@ -352,7 +350,7 @@ static ssize_t dbgfs_target_ids_write(struct file *file, nrs = kbuf; - targets = str_to_target_ids(nrs, ret, &nr_targets); + targets = str_to_target_ids(nrs, count, &nr_targets); if (!targets) { ret = -ENOMEM; goto out; @@ -378,11 +376,12 @@ static ssize_t dbgfs_target_ids_write(struct file *file, goto unlock_out; } - err = damon_set_targets(ctx, targets, nr_targets); - if (err) { + ret = damon_set_targets(ctx, targets, nr_targets); + if (ret) { if (targetid_is_pid(ctx)) dbgfs_put_pids(targets, nr_targets); - ret = err; + } else { + ret = count; } unlock_out: @@ -548,8 +547,7 @@ static ssize_t dbgfs_mk_context_write(struct file *file, { char *kbuf; char *ctx_name; - ssize_t ret = count; - int err; + ssize_t ret; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) @@ -567,9 +565,9 @@ static ssize_t dbgfs_mk_context_write(struct file *file, } mutex_lock(&damon_dbgfs_lock); - err = dbgfs_mk_context(ctx_name); - if (err) - ret = err; + ret = dbgfs_mk_context(ctx_name); + if (!ret) + ret = count; mutex_unlock(&damon_dbgfs_lock); out: @@ -638,8 +636,7 @@ static ssize_t dbgfs_rm_context_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { char *kbuf; - ssize_t ret = count; - int err; + ssize_t ret; char *ctx_name; kbuf = user_input_str(buf, count, ppos); @@ -658,9 +655,9 @@ static ssize_t dbgfs_rm_context_write(struct file *file, } mutex_lock(&damon_dbgfs_lock); - err = dbgfs_rm_context(ctx_name); - if (err) - ret = err; + ret = dbgfs_rm_context(ctx_name); + if (!ret) + ret = count; mutex_unlock(&damon_dbgfs_lock); out: @@ -684,9 +681,8 @@ static ssize_t dbgfs_monitor_on_read(struct file *file, static ssize_t dbgfs_monitor_on_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - ssize_t ret = count; + ssize_t ret; char *kbuf; - int err; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) @@ -699,14 +695,14 @@ static ssize_t dbgfs_monitor_on_write(struct file *file, } if (!strncmp(kbuf, "on", count)) - err = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs); + ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs); else if (!strncmp(kbuf, "off", count)) - err = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); + ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); else - err = -EINVAL; + ret = -EINVAL; - if (err) - ret = err; + if (!ret) + ret = count; kfree(kbuf); return ret; }