softlockup: add a /proc tuning parameter

[firefly-linux-kernel-4.4.55.git] / kernel / sysctl.c

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 5e63de0f9ee23dfd6bd1262984e6bb783a128231..dde3d53e8adc0fd8aabbf871d0b5c6751dfb9907 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -80,6 +80,19 @@ extern int maps_protect;
 extern int sysctl_stat_interval;
 extern int audit_argv_kb;
 
+/* Constants used for minimum and  maximum */
+#ifdef CONFIG_DETECT_SOFTLOCKUP
+static int one = 1;
+static int sixty = 60;
+#endif
+
+#ifdef CONFIG_MMU
+static int two = 2;
+#endif
+
+static int zero;
+static int one_hundred = 100;
+
 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 static int maxolduid = 65535;
 static int minolduid;
@@ -711,6 +724,19 @@ static ctl_table kern_table[] = {
                .proc_handler   = &proc_dointvec,
        },
 #endif
+#ifdef CONFIG_DETECT_SOFTLOCKUP
+       {
+               .ctl_name       = CTL_UNNUMBERED,
+               .procname       = "softlockup_thresh",
+               .data           = &softlockup_thresh,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = &proc_dointvec_minmax,
+               .strategy       = &sysctl_intvec,
+               .extra1         = &one,
+               .extra2         = &sixty,
+       },
+#endif
 #ifdef CONFIG_COMPAT
        {
                .ctl_name       = KERN_COMPAT_LOG,
@@ -757,13 +783,6 @@ static ctl_table kern_table[] = {
        { .ctl_name = 0 }
 };
 
-/* Constants for minimum and maximum testing in vm_table.
-   We use these as one-element integer vectors. */
-static int zero;
-static int two = 2;
-static int one_hundred = 100;
-
-
 static ctl_table vm_table[] = {
        {
                .ctl_name       = VM_OVERCOMMIT_MEMORY,