[RFC PATCH v5 04/16] watchdog/hardlockup: Define a generic function to detect hardlockups
From: Ricardo Neri <hidden>
Date: 2021-05-04 19:07:39
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
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. Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ashok Raj <redacted> Cc: Andi Kleen <redacted> Cc: Tony Luck <tony.luck@intel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Stephane Eranian <redacted> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: "Ravi V. Shankar" <redacted> Cc: x86@kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Ricardo Neri <redacted> --- 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