The procedure to detect hardlockups is independent of the underlying
mechanism that generates the non-maskable interrupt used to drive the
detector. Thus, it can be put in a separate, generic function. In this
manner, it can be invoked by various implementations of the NMI watchdog.
For this purpose, move the bulk of watchdog_overflow_callback() to the
new function inspect_for_hardlockups(). This function can then be called
from the applicable NMI handlers. No functional changes.
Cc: Andi Kleen <a...@linux.intel.com>
Cc: Nicholas Piggin <npig...@gmail.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Stephane Eranian <eran...@google.com>
Cc: "Ravi V. Shankar" <ravi.v.shan...@intel.com>
Cc: io...@lists.linux-foundation.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: x...@kernel.org
Reviewed-by: Tony Luck <tony.l...@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calde...@linux.intel.com>
---
Changes since v5:
* None
Changes since v4:
* None
Changes since v3:
* None
Changes since v2:
* None
Changes since v1:
* None
---
include/linux/nmi.h | 1 +
kernel/watchdog_hld.c | 18 +++++++++++-------
2 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index 750c7f395ca9..1b68f48ad440 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -207,6 +207,7 @@ int proc_nmi_watchdog(struct ctl_table *, int , void *,
size_t *, loff_t *);
int proc_soft_watchdog(struct ctl_table *, int , void *, size_t *, loff_t *);
int proc_watchdog_thresh(struct ctl_table *, int , void *, size_t *, loff_t *);
int proc_watchdog_cpumask(struct ctl_table *, int, void *, size_t *, loff_t *);
+void inspect_for_hardlockups(struct pt_regs *regs);
#ifdef CONFIG_HAVE_ACPI_APEI_NMI
#include <asm/nmi.h>
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index 247bf0b1582c..b352e507b17f 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -106,14 +106,8 @@ static struct perf_event_attr wd_hw_attr = {
.disabled = 1,
};
-/* Callback function for perf event subsystem */
-static void watchdog_overflow_callback(struct perf_event *event,
- struct perf_sample_data *data,
- struct pt_regs *regs)
+void inspect_for_hardlockups(struct pt_regs *regs)
{
- /* Ensure the watchdog never gets throttled */
- event->hw.interrupts = 0;
-
if (__this_cpu_read(watchdog_nmi_touch) == true) {
__this_cpu_write(watchdog_nmi_touch, false);
return;
@@ -163,6 +157,16 @@ static void watchdog_overflow_callback(struct perf_event
*event,
return;
}
+/* Callback function for perf event subsystem */
+static void watchdog_overflow_callback(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ /* Ensure the watchdog never gets throttled */
+ event->hw.interrupts = 0;
+ inspect_for_hardlockups(regs);
+}
+
static int hardlockup_detector_event_create(void)
{
unsigned int cpu = smp_processor_id();
--
2.17.1
