[tip:core/urgent] watchdog/core: Split out cpumask write function

tip-bot for Thomas Gleixner
2017-09-14T10:50:46Z

Commit-ID: 05ba3de74a3f499dcaa37b186220aaf174c95a4b
Gitweb: http://git.kernel.org/tip/05ba3de74a3f499dcaa37b186220aaf174c95a4b
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Tue, 12 Sep 2017 21:37:08 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 14 Sep 2017 11:41:06 +0200

watchdog/core: Split out cpumask write function

Split the write part of the cpumask proc handler out into a separate helper
to avoid deep indentation. This also reduces the patch complexity in the
following cleanups.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194147.218075991@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/watchdog.c | 40 +++++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 19 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index a9bdfde..cedf45a 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -792,10 +792,29 @@ static int watchdog_update_cpus(void)
if (IS_ENABLED(CONFIG_SOFTLOCKUP_DETECTOR)) {
return smpboot_update_cpumask_percpu_thread(&watchdog_threads,
&watchdog_cpumask);
+ __lockup_detector_cleanup();
}
return 0;
}

+static void proc_watchdog_cpumask_update(void)
+{
+ /* Remove impossible cpus to keep sysctl output clean. */
+ cpumask_and(&watchdog_cpumask, &watchdog_cpumask, cpu_possible_mask);
+
+ if (watchdog_running) {
+ /*
+ * Failure would be due to being unable to allocate a
+ * temporary cpumask, so we are likely not in a position to
+ * do much else to make things better.
+ */
+ if (watchdog_update_cpus() != 0)
+ pr_err("cpumask update failed\n");
+ }
+
+ watchdog_nmi_reconfigure();
+}
+
/*
* The cpumask is the mask of possible cpus that the watchdog can run
* on, not the mask of cpus it is actually running on. This allows the
@@ -811,30 +830,13 @@ int proc_watchdog_cpumask(struct ctl_table *table, int write,
mutex_lock(&watchdog_mutex);

err = proc_do_large_bitmap(table, write, buffer, lenp, ppos);
- if (!err && write) {
- /* Remove impossible cpus to keep sysctl output cleaner. */
- cpumask_and(&watchdog_cpumask, &watchdog_cpumask,
- cpu_possible_mask);
-
- if (watchdog_running) {
- /*
- * Failure would be due to being unable to allocate
- * a temporary cpumask, so we are likely not in a
- * position to do much else to make things better.
- */
- if (watchdog_update_cpus() != 0)
- pr_err("cpumask update failed\n");
- }
-
- watchdog_nmi_reconfigure();
- __lockup_detector_cleanup();
- }
+ if (!err && write)
+ proc_watchdog_cpumask_update();

mutex_unlock(&watchdog_mutex);
cpu_hotplug_enable();
return err;
}
-
#endif /* CONFIG_SYSCTL */

void __init lockup_detector_init(void)