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To provide visibility without causing additional log spam, emit a single aggregate summary line at the end of each watchdog scan when hung tasks are detected and the warning budget is exhausted. Keep per-task reports budgeted to avoid flooding dmesg or causing ring buffer overflows during system-wide hangs. Suggested-by: Petr Mladek Suggested-by: Lance Yang Signed-off-by: Aaron Tomlin --- kernel/hung_task.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 53499fbead83..f5eb75325f3a 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -268,7 +268,7 @@ static void hung_task_info(struct task_struct *t, unsigned long timeout, debug_show_blocker(t, timeout); if (!hung_task_warnings_printed) - pr_info("Future hung task reports are suppressed, see sysctl kernel.hung_task_warnings\n"); + pr_info("Future hung task reports won't print details about each process, see sysctl kernel.hung_task_warnings\n"); } touch_nmi_watchdog(); @@ -354,6 +354,10 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) return; } + if (!hung_task_warnings_printed && !hung_task_call_panic) + pr_info("hung_task: %lu hung tasks detected, warning budget exhausted\n", + this_round_count); + if (need_warning || hung_task_call_panic) { si_mask |= SYS_INFO_LOCKS; -- 2.55.0