When 'echo 4 > /proc/sys/vm/drop_caches' the message is disabled,
but there is no interface to enable the message, only by restarting
the way, so I want to add the 'echo 0 > /proc/sys/vm/drop_caches'
way to enabled the message again.
Signed-off-by: Ruiwu Chen <rwchen404@xxxxxxxxx>
---
fs/drop_caches.c | 7 +++++--
kernel/sysctl.c | 2 +-
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index d45ef541d848..c90cfaf9756d 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -57,7 +57,7 @@ int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
if (ret)
return ret;
if (write) {
- static int stfu;
+ static bool stfu;
if (sysctl_drop_caches & 1) {
lru_add_drain_all();
@@ -73,7 +73,10 @@ int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
current->comm, task_pid_nr(current),
sysctl_drop_caches);
}
- stfu |= sysctl_drop_caches & 4;
+ if (sysctl_drop_caches == 0)
+ stfu = false;
+ else if (sysctl_drop_caches == 4)
+ stfu = true;
}
return 0;
}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index cb57da499ebb..f2e06e074724 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2088,7 +2088,7 @@ static const struct ctl_table vm_table[] = {
.maxlen = sizeof(int),
.mode = 0200,
.proc_handler = drop_caches_sysctl_handler,
- .extra1 = SYSCTL_ONE,
+ .extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_FOUR,
},
{
--
2.27.0
