lkml.org 
[lkml]   [2023]   [Oct]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[v3 3/3] mm, migrc: Add a sysctl knob to enable/disable MIGRC mechanism
Date
Add a sysctl knob, '/proc/sys/vm/migrc_enable' to switch on/off migrc.

Signed-off-by: Byungchul Park <byungchul@sk.com>
---
mm/migrate.c | 44 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index 76278eca8417..f6bbdc2d4fb1 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -58,6 +58,48 @@
#include "internal.h"

#ifdef CONFIG_MIGRC
+static int sysctl_migrc_enable = 1;
+#ifdef CONFIG_SYSCTL
+static int sysctl_migrc_enable_handler(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table t;
+ int err;
+ int enabled = sysctl_migrc_enable;
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ t = *table;
+ t.data = &enabled;
+ err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos);
+ if (err < 0)
+ return err;
+ if (write)
+ sysctl_migrc_enable = enabled;
+ return err;
+}
+
+static struct ctl_table migrc_sysctls[] = {
+ {
+ .procname = "migrc_enable",
+ .data = NULL, /* filled in by handler */
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = sysctl_migrc_enable_handler,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {}
+};
+
+static int __init migrc_sysctl_init(void)
+{
+ register_sysctl_init("vm", migrc_sysctls);
+ return 0;
+}
+late_initcall(migrc_sysctl_init);
+#endif

atomic_t migrc_gen;

@@ -242,7 +284,7 @@ static inline bool migrc_stopped_pending(void)

static bool can_migrc_system(void)
{
- return !migrc_stopped_pending();
+ return sysctl_migrc_enable && !migrc_stopped_pending();
}
#else
static inline void migrc_mark_folios(struct folio *fsrc, struct folio *fdst) {}
--
2.17.1
\
 
 \ /
  Last update: 2023-10-30 08:42    [W:0.232 / U:0.312 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site