watchdog: Reduce message verbosity
PATCH v2 1/1 watchdog: Reduce message verbosity
Code is emitting the following error message during boot on systems without PMU hardware support while probing NMI capability.
NMI watchdog: Perf event create on CPU 0 failed with -2
This error is coming from this path:
lockup_detector_init
watchdog_nmi_probe
hardlockup_detector_perf_init
hardlockup_detector_event_create
perf_event_create_kernel_counter
perf_event_alloc
perf_init_event (9539)
pmu = ERR_PTR(-ENOENT) due to lack of PMUs in the system
followed by the warning that NMI watchdog is disabled as follows.
NMI watchdog: Perf NMI watchdog permanently disabled
While NMI disabled information is usefel for ordinary users, seeing a PERF event create failed with error code -2 is too verbose.
Reducing the message severity to debug so that if somebody is really wants to debug this, they can find out the error source by increasing the kernel loglevel during boot.
--- kernel/watchdog_hld.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
kernel/watchdog_hld.c +2 -2
@@ -175,8 +175,8 @@ static int hardlockup_detector_event_create(void) evt =perf_event_create_kernel_counter (wd_attr, cpu,NULL , watchdog_overflow_callback,NULL );if (IS_ERR (evt)) { -pr_info ("Perf event create on CPU %d failed with %ld\n" , cpu, -PTR_ERR (evt)); +pr_debug ("Perf event create on CPU %d failed with %ld\n" , cpu, +PTR_ERR (evt));return PTR_ERR (evt); }this_cpu_write (watchdog_ev, evt);
Signature · 1 line
2.17.1
tip-bot for Sinan Kaya
merge botwatchdog: Reduce message verbosity
Commit-ID: 1b6266ebe3da8198e9a02fbad77bbb56e2f7ce2e Gitweb: https://git.kernel.org/tip/1b6266ebe3da8198e9a02fbad77bbb56e2f7ce2e Author: Sinan Kaya <[email protected]> AuthorDate: Thu, 2 Aug 2018 23:09:41 -0700 Committer: Thomas Gleixner <[email protected]> CommitDate: Fri, 3 Aug 2018 12:19:08 +0200
watchdog: Reduce message verbosity
Code is emitting the following error message during boot on systems without PMU hardware support while probing NMI capability.
NMI watchdog: Perf event create on CPU 0 failed with -2
This error is emitted as the perf subsystem returns -ENOENT due to lack of PMUs in the system.
It is followed by the warning that NMI watchdog is disabled:
NMI watchdog: Perf NMI watchdog permanently disabled
While NMI disabled information is useful for ordinary users, seeing a PERF event create failed with error code -2 is not.
Reduce the message severity to debug so that if debugging is still possible in case the error code returned by perf is required for analysis.
--- kernel/watchdog_hld.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
kernel/watchdog_hld.c +2 -2
@@ -175,8 +175,8 @@ static int hardlockup_detector_event_create(void) evt =perf_event_create_kernel_counter (wd_attr, cpu,NULL , watchdog_overflow_callback,NULL );if (IS_ERR (evt)) { -pr_info ("Perf event create on CPU %d failed with %ld\n" , cpu, -PTR_ERR (evt)); +pr_debug ("Perf event create on CPU %d failed with %ld\n" , cpu, +PTR_ERR (evt));return PTR_ERR (evt); }this_cpu_write (watchdog_ev, evt);