[PATCH 3/4] watchdog: move watchdog sysctl to watchdog.c
From: Xiaoming Ni
Date: Fri May 15 2020 - 00:34:10 EST
Move watchdog sysctl interface to watchdog.c.
Use register_sysctl() to register the sysctl interface to avoid
merge conflicts when different features modify sysctl.c at the same time.
Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
---
kernel/sysctl.c | 96 --------------------------------------------
kernel/watchdog.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 117 insertions(+), 96 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 01fc559..e394990 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -97,9 +97,6 @@
#ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
#include <linux/stackleak.h>
#endif
-#ifdef CONFIG_LOCKUP_DETECTOR
-#include <linux/nmi.h>
-#endif
#if defined(CONFIG_SYSCTL)
@@ -120,9 +117,6 @@
#endif
/* Constants used for minimum and maximum */
-#ifdef CONFIG_LOCKUP_DETECTOR
-static int sixty = 60;
-#endif
static int __maybe_unused two = 2;
static int __maybe_unused four = 4;
@@ -887,96 +881,6 @@ static int sysrq_sysctl_handler(struct ctl_table *table, int write,
.mode = 0444,
.proc_handler = proc_dointvec,
},
-#if defined(CONFIG_LOCKUP_DETECTOR)
- {
- .procname = "watchdog",
- .data = &watchdog_user_enabled,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_watchdog,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- {
- .procname = "watchdog_thresh",
- .data = &watchdog_thresh,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_watchdog_thresh,
- .extra1 = SYSCTL_ZERO,
- .extra2 = &sixty,
- },
- {
- .procname = "nmi_watchdog",
- .data = &nmi_watchdog_user_enabled,
- .maxlen = sizeof(int),
- .mode = NMI_WATCHDOG_SYSCTL_PERM,
- .proc_handler = proc_nmi_watchdog,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- {
- .procname = "watchdog_cpumask",
- .data = &watchdog_cpumask_bits,
- .maxlen = NR_CPUS,
- .mode = 0644,
- .proc_handler = proc_watchdog_cpumask,
- },
-#ifdef CONFIG_SOFTLOCKUP_DETECTOR
- {
- .procname = "soft_watchdog",
- .data = &soft_watchdog_user_enabled,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_soft_watchdog,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- {
- .procname = "softlockup_panic",
- .data = &softlockup_panic,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
-#ifdef CONFIG_SMP
- {
- .procname = "softlockup_all_cpu_backtrace",
- .data = &sysctl_softlockup_all_cpu_backtrace,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
-#endif /* CONFIG_SMP */
-#endif
-#ifdef CONFIG_HARDLOCKUP_DETECTOR
- {
- .procname = "hardlockup_panic",
- .data = &hardlockup_panic,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
-#ifdef CONFIG_SMP
- {
- .procname = "hardlockup_all_cpu_backtrace",
- .data = &sysctl_hardlockup_all_cpu_backtrace,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
-#endif /* CONFIG_SMP */
-#endif
-#endif
-
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
{
.procname = "unknown_nmi_panic",
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index b6b1f54..05e1d58 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -23,6 +23,9 @@
#include <linux/sched/debug.h>
#include <linux/sched/isolation.h>
#include <linux/stop_machine.h>
+#ifdef CONFIG_SYSCTL
+#include <linux/kmemleak.h>
+#endif
#include <asm/irq_regs.h>
#include <linux/kvm_para.h>
@@ -756,10 +759,124 @@ int proc_watchdog_cpumask(struct ctl_table *table, int write,
mutex_unlock(&watchdog_mutex);
return err;
}
+
+static int sixty = 60;
+
+static struct ctl_table watchdog_sysctls[] = {
+ {
+ .procname = "watchdog",
+ .data = &watchdog_user_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_watchdog,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {
+ .procname = "watchdog_thresh",
+ .data = &watchdog_thresh,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_watchdog_thresh,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = &sixty,
+ },
+ {
+ .procname = "nmi_watchdog",
+ .data = &nmi_watchdog_user_enabled,
+ .maxlen = sizeof(int),
+ .mode = NMI_WATCHDOG_SYSCTL_PERM,
+ .proc_handler = proc_nmi_watchdog,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {
+ .procname = "watchdog_cpumask",
+ .data = &watchdog_cpumask_bits,
+ .maxlen = NR_CPUS,
+ .mode = 0644,
+ .proc_handler = proc_watchdog_cpumask,
+ },
+#ifdef CONFIG_SOFTLOCKUP_DETECTOR
+ {
+ .procname = "soft_watchdog",
+ .data = &soft_watchdog_user_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_soft_watchdog,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {
+ .procname = "softlockup_panic",
+ .data = &softlockup_panic,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+#ifdef CONFIG_SMP
+ {
+ .procname = "softlockup_all_cpu_backtrace",
+ .data = &sysctl_softlockup_all_cpu_backtrace,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+#endif /* CONFIG_SMP */
+#endif
+#ifdef CONFIG_HARDLOCKUP_DETECTOR
+ {
+ .procname = "hardlockup_panic",
+ .data = &hardlockup_panic,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+#ifdef CONFIG_SMP
+ {
+ .procname = "hardlockup_all_cpu_backtrace",
+ .data = &sysctl_hardlockup_all_cpu_backtrace,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+#endif /* CONFIG_SMP */
+#endif
+ {}
+};
+
+/*
+ * The watchdog sysctl has a default value.
+ * Even if register_sysctl() fails, it does not affect the main function of
+ * the watchdog. At the same time, during the system initialization phase,
+ * malloc small memory will almost never fail.
+ * So the return value is ignored here
+ */
+static void __init watchdog_sysctl_init(void)
+{
+ struct ctl_table_header *p = register_sysctl("kernel", watchdog_sysctls);
+
+ if (unlikely(!p)) {
+ pr_err("%s fail\n", __func__);
+ return;
+ }
+ kmemleak_not_leak(p);
+}
+#else
+#define watchdog_sysctl_init() do { } while (0)
#endif /* CONFIG_SYSCTL */
void __init lockup_detector_init(void)
{
+ watchdog_sysctl_init();
if (tick_nohz_full_enabled())
pr_info("Disabling watchdog on nohz_full cores by default\n");
--
1.8.5.6