diff options
| author | Olav Haugan <ohaugan@codeaurora.org> | 2016-08-18 16:49:44 -0700 |
|---|---|---|
| committer | Olav Haugan <ohaugan@codeaurora.org> | 2016-09-20 17:47:13 -0700 |
| commit | 3fe956359cd3f1cd174285b693b424f89123ff96 (patch) | |
| tree | 8093d51adfbff49af39bc775fdf92f355b71a374 /kernel/watchdog.c | |
| parent | dcf716301e77728f08667cf0189d6de1cdc5e5e9 (diff) | |
watchdog: Add support for cpu isolation
Open up interface to allow external subsystem to enable and disable hard
lockup detector.
Change-Id: I88a728ee1d54aaa887fab52e5e40d1d4e4fc69ca
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Diffstat (limited to 'kernel/watchdog.c')
| -rw-r--r-- | kernel/watchdog.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 029da92fb712..7f21591c8ec5 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -13,6 +13,7 @@ #include <linux/mm.h> #include <linux/cpu.h> +#include <linux/device.h> #include <linux/nmi.h> #include <linux/init.h> #include <linux/module.h> @@ -95,6 +96,7 @@ static u64 __read_mostly sample_period; static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts); static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog); static DEFINE_PER_CPU(struct hrtimer, watchdog_hrtimer); +static DEFINE_PER_CPU(unsigned int, watchdog_en); static DEFINE_PER_CPU(bool, softlockup_touch_sync); static DEFINE_PER_CPU(bool, soft_watchdog_warn); static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts); @@ -586,9 +588,17 @@ static void watchdog_set_prio(unsigned int policy, unsigned int prio) sched_setscheduler(current, policy, ¶m); } -static void watchdog_enable(unsigned int cpu) +/* Must be called with hotplug lock (lock_device_hotplug()) held. */ +void watchdog_enable(unsigned int cpu) { struct hrtimer *hrtimer = raw_cpu_ptr(&watchdog_hrtimer); + unsigned int *enabled = raw_cpu_ptr(&watchdog_en); + + lock_device_hotplug_assert(); + + if (*enabled) + return; + *enabled = 1; /* kick off the timer for the hardlockup detector */ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); @@ -606,9 +616,17 @@ static void watchdog_enable(unsigned int cpu) __touch_watchdog(); } -static void watchdog_disable(unsigned int cpu) +/* Must be called with hotplug lock (lock_device_hotplug()) held. */ +void watchdog_disable(unsigned int cpu) { struct hrtimer *hrtimer = raw_cpu_ptr(&watchdog_hrtimer); + unsigned int *enabled = raw_cpu_ptr(&watchdog_en); + + lock_device_hotplug_assert(); + + if (!*enabled) + return; + *enabled = 0; watchdog_set_prio(SCHED_NORMAL, 0); hrtimer_cancel(hrtimer); |