watchdog/perf: add a weak function for an arch to detect if perf can use NMIs

On arm64, NMI support needs to be detected at runtime.  Add a weak
function to the perf hardlockup detector so that an architecture can
implement it to detect whether NMIs are available.

Link: https://lkml.kernel.org/r/20230519101840.v5.15.Ic55cb6f90ef5967d8aaa2b503a4e67c753f64d3a@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Colin Cross <ccross@android.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masayoshi Mizuma <msys.mizuma@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Tzung-Bi Shih <tzungbi@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Douglas Anderson 2023-05-19 10:18:39 -07:00 committed by Andrew Morton
parent 1f423c905a
commit b17aa95933
2 changed files with 12 additions and 1 deletions

View File

@ -208,6 +208,7 @@ static inline bool trigger_single_cpu_backtrace(int cpu)
#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
u64 hw_nmi_get_sample_period(int watchdog_thresh);
bool arch_perf_nmi_is_available(void);
#endif
#if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \

View File

@ -234,12 +234,22 @@ void __init hardlockup_detector_perf_restart(void)
}
}
bool __weak __init arch_perf_nmi_is_available(void)
{
return true;
}
/**
* watchdog_hardlockup_probe - Probe whether NMI event is available at all
*/
int __init watchdog_hardlockup_probe(void)
{
int ret = hardlockup_detector_event_create();
int ret;
if (!arch_perf_nmi_is_available())
return -ENODEV;
ret = hardlockup_detector_event_create();
if (ret) {
pr_info("Perf NMI watchdog permanently disabled\n");