The procedure to detect hardlockups is independent of the underlying
mechanism that generated 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.
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Cc: Andi Kleen <andi.kleen@xxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Don Zickus <dzickus@xxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Babu Moger <babu.moger@xxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Philippe Ombredanne <pombredanne@xxxxxxxx>
Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Cc: "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx>
Cc: "Ravi V. Shankar" <ravi.v.shankar@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: sparclinux@xxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
---
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 9003e29cde46..5a8b19749769 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -212,6 +212,7 @@ extern int proc_watchdog_thresh(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
extern int proc_watchdog_cpumask(struct ctl_table *, int,
void __user *, 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 71381168dede..9724cd57307b 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;
@@ -162,6 +156,16 @@ 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
