For some features (such as hang_task, ledtrig-activity, ledtrig-heartbeat) different processing logics need to be performed based on whether the current system is in panic state: 1: Register hook for panic_notifier_list. 2. Assign a value to the global variable in the hook function. 3. Determine whether the system is in panic state based on the global variable and perform different processing. Duplicate code snippets exist, and the timing judgment is relatively lag. Therefore, consider extracting the new API: bool in_panic_state(void). ---------------- v2: Rename api to in_panic_state as recommended by Pavel Machek, Tetsuo Handa, Randy Dunlap. v1: https://lore.kernel.org/lkml/20201218114406.61906-1-nixiaoming@xxxxxxxxxx/ API name: is_being_panic ---------------- Xiaoming Ni (4): panic: Add new API in_panic_state() hung_task: Replace "did_panic" with in_panic_state() leds:trigger:ledtrig-activity Replace "panic_detected" with in_panic_state() leds:trigger:ledtrig-heartbeat: Replace "panic_heartbeats" with in_panic_state() drivers/leds/trigger/ledtrig-activity.c | 19 +------------------ drivers/leds/trigger/ledtrig-heartbeat.c | 19 +------------------ include/linux/kernel.h | 1 + kernel/hung_task.c | 17 +---------------- kernel/panic.c | 6 ++++++ 5 files changed, 10 insertions(+), 52 deletions(-) -- 2.27.0