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Date:   Thu, 25 Feb 2021 15:12:10 -0800 (PST)
From:   Hugh Dickins <hughd@google.com>
To:     Andrew Morton <akpm@linux-foundation.org>
cc:     Roman Gushchin <guro@fb.com>, Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH 2/4] mm: no more EINVAL from /proc/sys/vm/stat_refresh
In-Reply-To: <alpine.LSU.2.11.2102251502240.13363@eggly.anvils>
Message-ID: <alpine.LSU.2.11.2102251510410.13363@eggly.anvils>
References: <alpine.LSU.2.11.2102251502240.13363@eggly.anvils>
User-Agent: Alpine 2.11 (LSU 23 2013-08-11)
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EINVAL was good for drawing the refresher's attention to a warning in
dmesg, but became very tiresome when running test suites scripted with
"set -e": an underflow from a bug in one feature would cause unrelated
tests much later to fail, just because their /proc/sys/vm/stat_refresh
touch failed with that error. Stop doing that.

Signed-off-by: Hugh Dickins <hughd@google.com>
---

 mm/vmstat.c |    5 -----
 1 file changed, 5 deletions(-)

--- vmstat1/mm/vmstat.c	2021-02-25 11:50:36.000000000 -0800
+++ vmstat2/mm/vmstat.c	2021-02-25 11:56:18.000000000 -0800
@@ -1844,7 +1844,6 @@ int vmstat_refresh(struct ctl_table *tab
 		if (val < 0) {
 			pr_warn("%s: %s %ld\n",
 				__func__, zone_stat_name(i), val);
-			err = -EINVAL;
 		}
 	}
 #ifdef CONFIG_NUMA
@@ -1853,7 +1852,6 @@ int vmstat_refresh(struct ctl_table *tab
 		if (val < 0) {
 			pr_warn("%s: %s %ld\n",
 				__func__, numa_stat_name(i), val);
-			err = -EINVAL;
 		}
 	}
 #endif
@@ -1862,11 +1860,8 @@ int vmstat_refresh(struct ctl_table *tab
 		if (val < 0) {
 			pr_warn("%s: %s %ld\n",
 				__func__, node_stat_name(i), val);
-			err = -EINVAL;
 		}
 	}
-	if (err)
-		return err;
 	if (write)
 		*ppos += *lenp;
 	else