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[23.128.96.18]) by mx.google.com with ESMTP id s197si20049106pfc.152.2021.10.13.06.11.25; Wed, 13 Oct 2021 06:11:51 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234056AbhJMNLH (ORCPT + 99 others); Wed, 13 Oct 2021 09:11:07 -0400 Received: from out30-57.freemail.mail.aliyun.com ([115.124.30.57]:46413 "EHLO out30-57.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231294AbhJMNLH (ORCPT ); Wed, 13 Oct 2021 09:11:07 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=rongwei.wang@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0UrhCxCT_1634130541; Received: from localhost.localdomain(mailfrom:rongwei.wang@linux.alibaba.com fp:SMTPD_---0UrhCxCT_1634130541) by smtp.aliyun-inc.com(127.0.0.1); Wed, 13 Oct 2021 21:09:02 +0800 From: Rongwei Wang To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: sj@kernel.org, akpm@linux-foundation.org Subject: [PATCH] mm/damon/dbgfs: remove unnecessary variables Date: Wed, 13 Oct 2021 21:09:01 +0800 Message-Id: <20211013130901.1017-1-rongwei.wang@linux.alibaba.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 | 67 ++++++++++++++++++++++-------------------------- 1 file changed, 31 insertions(+), 36 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 28d6abf27763..d8dd68f72827 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; @@ -378,12 +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 < 0) { if (targetid_is_pid(ctx)) dbgfs_put_pids(targets, nr_targets); - ret = err; - } + } else + ret = count; unlock_out: mutex_unlock(&ctx->kdamond_lock); @@ -548,8 +546,7 @@ 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 +564,9 @@ 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 +635,7 @@ 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 +654,9 @@ 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 +680,8 @@ 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 +694,14 @@ 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; } -- 2.27.0