From 83a80a39075a9ded23df1e26a4b617c289077630 Mon Sep 17 00:00:00 2001
From: Ulrich Obergfell <uobergfe@redhat.com>
Date: Tue, 14 Apr 2015 15:44:08 -0700
Subject: [PATCH] watchdog: introduce separate handlers for parameters in
 /proc/sys/kernel

Separate handlers for each watchdog parameter in /proc/sys/kernel replace
the proc_dowatchdog() function.  Three of those handlers merely call
proc_watchdog_common() with one different argument.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 include/linux/nmi.h |  8 ++++++
 kernel/watchdog.c   | 59 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index 3885a7d12bd2..5b5450585b8a 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -74,6 +74,14 @@ extern int watchdog_user_enabled;
 extern int watchdog_thresh;
 extern int sysctl_softlockup_all_cpu_backtrace;
 struct ctl_table;
+extern int proc_watchdog(struct ctl_table *, int ,
+			 void __user *, size_t *, loff_t *);
+extern int proc_nmi_watchdog(struct ctl_table *, int ,
+			     void __user *, size_t *, loff_t *);
+extern int proc_soft_watchdog(struct ctl_table *, int ,
+			      void __user *, size_t *, loff_t *);
+extern int proc_watchdog_thresh(struct ctl_table *, int ,
+				void __user *, size_t *, loff_t *);
 extern int proc_dowatchdog(struct ctl_table *, int ,
 			   void __user *, size_t *, loff_t *);
 #endif
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 3600a01c97a9..26002ed4c16e 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -768,6 +768,65 @@ static int proc_watchdog_common(int which, struct ctl_table *table, int write,
 	return err;
 }
 
+/*
+ * /proc/sys/kernel/watchdog
+ */
+int proc_watchdog(struct ctl_table *table, int write,
+		  void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return proc_watchdog_common(NMI_WATCHDOG_ENABLED|SOFT_WATCHDOG_ENABLED,
+				    table, write, buffer, lenp, ppos);
+}
+
+/*
+ * /proc/sys/kernel/nmi_watchdog
+ */
+int proc_nmi_watchdog(struct ctl_table *table, int write,
+		      void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return proc_watchdog_common(NMI_WATCHDOG_ENABLED,
+				    table, write, buffer, lenp, ppos);
+}
+
+/*
+ * /proc/sys/kernel/soft_watchdog
+ */
+int proc_soft_watchdog(struct ctl_table *table, int write,
+			void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return proc_watchdog_common(SOFT_WATCHDOG_ENABLED,
+				    table, write, buffer, lenp, ppos);
+}
+
+/*
+ * /proc/sys/kernel/watchdog_thresh
+ */
+int proc_watchdog_thresh(struct ctl_table *table, int write,
+			 void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	int err, old;
+
+	mutex_lock(&watchdog_proc_mutex);
+
+	old = ACCESS_ONCE(watchdog_thresh);
+	err = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+
+	if (err || !write)
+		goto out;
+
+	/*
+	 * Update the sample period.
+	 * Restore 'watchdog_thresh' on failure.
+	 */
+	set_sample_period();
+	err = proc_watchdog_update();
+	if (err)
+		watchdog_thresh = old;
+out:
+	mutex_unlock(&watchdog_proc_mutex);
+	return err;
+}
+
 /*
  * proc handler for /proc/sys/kernel/nmi_watchdog,watchdog_thresh
  */
-- 
GitLab