Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Liu Shixin <liushixin2@huawei.com>
To:     Seth Jennings <sjenning@redhat.com>,
        Dan Streetman <ddstreet@ieee.org>,
        Vitaly Wool <vitaly.wool@konsulko.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Christoph Hellwig <hch@lst.de>
CC:     <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>,
        Liu Shixin <liushixin2@huawei.com>
Subject: [PATCH -next v7 2/4] mm/zswap: skip invalid or unchanged parameter
Date:   Sat, 25 Mar 2023 15:14:18 +0800
Message-ID: <20230325071420.2246461-3-liushixin2@huawei.com>
In-Reply-To: <20230325071420.2246461-1-liushixin2@huawei.com>
References: <20230325071420.2246461-1-liushixin2@huawei.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 7BIT
Content-Type:   text/plain; charset=US-ASCII
Precedence: bulk

If parameter is invalid or no change required, return directly. This can
reduces unnecessary printing.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
 mm/zswap.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index 6d2b879f091e..d2adc1ffe47d 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -761,15 +761,15 @@ static int __zswap_param_set(const char *val, const struct kernel_param *kp,
 	char *s = strstrip((char *)val);
 	int ret;
 
+	/* no change required */
+	if (!strcmp(s, *(char **)kp->arg) && zswap_has_pool)
+		return 0;
+
 	if (zswap_init_failed) {
 		pr_err("can't set param, initialization failed\n");
 		return -ENODEV;
 	}
 
-	/* no change required */
-	if (!strcmp(s, *(char **)kp->arg) && zswap_has_pool)
-		return 0;
-
 	/* if this is load-time (pre-init) param setting,
 	 * don't create a pool; that's done during init.
 	 */
@@ -864,6 +864,15 @@ static int zswap_zpool_param_set(const char *val,
 static int zswap_enabled_param_set(const char *val,
 				   const struct kernel_param *kp)
 {
+	bool res;
+
+	if (kstrtobool(val, &res))
+		return -EINVAL;
+
+	/* no change required */
+	if (res == *(bool *)kp->arg)
+		return 0;
+
 	if (zswap_init_failed) {
 		pr_err("can't enable, initialization failed\n");
 		return -ENODEV;
-- 
2.25.1