watchdog, hung_task_timeout: Add Kconfig configurable default (e11feaa1) · Commits · 戴 / test

This patch allows the default value for sysctl_hung_task_timeout_secs to be set at build time. The feature carries virtually no overhead, so it makes sense to keep it enabled. On heavily loaded systems, though, it can end up triggering stack traces when there is no bug other than the system being underprovisioned. We use this patch to keep the hung task facility available but disabled at boot-time. The default of 120 seconds is preserved. As a note, commit may have accidentally reverted commit , which raised the default from 120 seconds to 480 seconds. Signed-off-by:

Jeff Mahoney <jeffm@suse.com> Acked-by:

Mandeep Singh Baines <msb@google.com> Link: http://lkml.kernel.org/r/4DB8600C.8080000@suse.com Signed-off-by:

Ingo Molnar <mingo@elte.hu>

kernel/hung_task.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -33,7 +33,7 @@ unsigned long __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;
		/*
		* Zero means infinite timeout - no checking done:
		*/
		unsigned long __read_mostly sysctl_hung_task_timeout_secs = 120;
		unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT;

		unsigned long __read_mostly sysctl_hung_task_warnings = 10;

lib/Kconfig.debug

+15 −0

Original line number	Diff line number	Diff line
		@@ -238,6 +238,21 @@ config DETECT_HUNG_TASK
		enabled then all held locks will also be reported. This
		feature has negligible overhead.

		config DEFAULT_HUNG_TASK_TIMEOUT
		int "Default timeout for hung task detection (in seconds)"
		depends on DETECT_HUNG_TASK
		default 120
		help
		This option controls the default timeout (in seconds) used
		to determine when a task has become non-responsive and should
		be considered hung.

		It can be adjusted at runtime via the kernel.hung_task_timeout
		sysctl or by writing a value to /proc/sys/kernel/hung_task_timeout.

		A timeout of 0 disables the check. The default is two minutes.
		Keeping the default should be fine in most cases.

		config BOOTPARAM_HUNG_TASK_PANIC
		bool "Panic (Reboot) On Hung Tasks"
		depends on DETECT_HUNG_TASK

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