diff options
Diffstat (limited to 'kernel/hung_task.c')
| -rw-r--r-- | kernel/hung_task.c | 56 |
1 files changed, 38 insertions, 18 deletions
diff --git a/kernel/hung_task.c b/kernel/hung_task.c index b2c1f14b8129..d2254c91450b 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -24,6 +24,7 @@ #include <linux/sched/sysctl.h> #include <linux/hung_task.h> #include <linux/rwsem.h> +#include <linux/sys_info.h> #include <trace/events/sched.h> @@ -50,7 +51,6 @@ static unsigned long __read_mostly sysctl_hung_task_detect_count; * Zero means infinite timeout - no checking done: */ unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT; -EXPORT_SYMBOL_GPL(sysctl_hung_task_timeout_secs); /* * Zero (default value) means use sysctl_hung_task_timeout_secs: @@ -60,12 +60,17 @@ static unsigned long __read_mostly sysctl_hung_task_check_interval_secs; static int __read_mostly sysctl_hung_task_warnings = 10; static int __read_mostly did_panic; -static bool hung_task_show_lock; static bool hung_task_call_panic; -static bool hung_task_show_all_bt; static struct task_struct *watchdog_task; +/* + * A bitmask to control what kinds of system info to be printed when + * a hung task is detected, it could be task, memory, lock etc. Refer + * include/linux/sys_info.h for detailed bit definition. + */ +static unsigned long hung_task_si_mask; + #ifdef CONFIG_SMP /* * Should we dump all CPUs backtraces in a hung task event? @@ -81,7 +86,7 @@ static unsigned int __read_mostly sysctl_hung_task_all_cpu_backtrace; * hung task is detected: */ static unsigned int __read_mostly sysctl_hung_task_panic = - IS_ENABLED(CONFIG_BOOTPARAM_HUNG_TASK_PANIC); + CONFIG_BOOTPARAM_HUNG_TASK_PANIC; static int hung_task_panic(struct notifier_block *this, unsigned long event, void *ptr) @@ -218,8 +223,11 @@ static inline void debug_show_blocker(struct task_struct *task, unsigned long ti } #endif -static void check_hung_task(struct task_struct *t, unsigned long timeout) +static void check_hung_task(struct task_struct *t, unsigned long timeout, + unsigned long prev_detect_count) { + unsigned long total_hung_task; + if (!task_is_hung(t, timeout)) return; @@ -229,11 +237,11 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout) */ sysctl_hung_task_detect_count++; + total_hung_task = sysctl_hung_task_detect_count - prev_detect_count; trace_sched_process_hang(t); - if (sysctl_hung_task_panic) { + if (sysctl_hung_task_panic && total_hung_task >= sysctl_hung_task_panic) { console_verbose(); - hung_task_show_lock = true; hung_task_call_panic = true; } @@ -256,10 +264,7 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout) " disables this message.\n"); sched_show_task(t); debug_show_blocker(t, timeout); - hung_task_show_lock = true; - if (sysctl_hung_task_all_cpu_backtrace) - hung_task_show_all_bt = true; if (!sysctl_hung_task_warnings) pr_info("Future hung task reports are suppressed, see sysctl kernel.hung_task_warnings\n"); } @@ -300,6 +305,9 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) int max_count = sysctl_hung_task_check_count; unsigned long last_break = jiffies; struct task_struct *g, *t; + unsigned long prev_detect_count = sysctl_hung_task_detect_count; + int need_warning = sysctl_hung_task_warnings; + unsigned long si_mask = hung_task_si_mask; /* * If the system crashed already then all bets are off, @@ -308,7 +316,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) if (test_taint(TAINT_DIE) || did_panic) return; - hung_task_show_lock = false; + rcu_read_lock(); for_each_process_thread(g, t) { @@ -320,18 +328,23 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) last_break = jiffies; } - check_hung_task(t, timeout); + check_hung_task(t, timeout, prev_detect_count); } unlock: rcu_read_unlock(); - if (hung_task_show_lock) - debug_show_all_locks(); - if (hung_task_show_all_bt) { - hung_task_show_all_bt = false; - trigger_all_cpu_backtrace(); + if (!(sysctl_hung_task_detect_count - prev_detect_count)) + return; + + if (need_warning || hung_task_call_panic) { + si_mask |= SYS_INFO_LOCKS; + + if (sysctl_hung_task_all_cpu_backtrace) + si_mask |= SYS_INFO_ALL_BT; } + sys_info(si_mask); + if (hung_task_call_panic) panic("hung_task: blocked tasks"); } @@ -389,7 +402,7 @@ static const struct ctl_table hung_task_sysctls[] = { .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .extra2 = SYSCTL_INT_MAX, }, { .procname = "hung_task_check_count", @@ -430,6 +443,13 @@ static const struct ctl_table hung_task_sysctls[] = { .mode = 0444, .proc_handler = proc_doulongvec_minmax, }, + { + .procname = "hung_task_sys_info", + .data = &hung_task_si_mask, + .maxlen = sizeof(hung_task_si_mask), + .mode = 0644, + .proc_handler = sysctl_sys_info_handler, + }, }; static void __init hung_task_sysctl_init(void) |