There is no need the ledtriger to be called *that* early in the hotplug process (+ with disabled interrupts). As explained by Jacek Anaszewski [0] there is no need for it. Therefore this patch moves it to the ONLINE/PREPARE_DOWN level using the dynamic registration for the id.
[0] https://lkml.kernel.org/r/[email protected] Cc: Jacek Anaszewski <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Paul Gortmaker <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Richard Purdie <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Sebastian Andrzej Siewior <[email protected]> --- drivers/leds/trigger/ledtrig-cpu.c | 16 ++++++++-------- include/linux/cpuhotplug.h | 1 - 2 files changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/leds/trigger/ledtrig-cpu.c b/drivers/leds/trigger/ledtrig-cpu.c index 4a6a182d0a88..22f0634dd3fa 100644 --- a/drivers/leds/trigger/ledtrig-cpu.c +++ b/drivers/leds/trigger/ledtrig-cpu.c @@ -92,13 +92,13 @@ static struct syscore_ops ledtrig_cpu_syscore_ops = { .resume = ledtrig_cpu_syscore_resume, }; -static int ledtrig_starting_cpu(unsigned int cpu) +static int ledtrig_online_cpu(unsigned int cpu) { ledtrig_cpu(CPU_LED_START); return 0; } -static int ledtrig_dying_cpu(unsigned int cpu) +static int ledtrig_prepare_down_cpu(unsigned int cpu) { ledtrig_cpu(CPU_LED_STOP); return 0; @@ -107,6 +107,7 @@ static int ledtrig_dying_cpu(unsigned int cpu) static int __init ledtrig_cpu_init(void) { int cpu; + int ret; /* Supports up to 9999 cpu cores */ BUILD_BUG_ON(CONFIG_NR_CPUS > 9999); @@ -126,12 +127,11 @@ static int __init ledtrig_cpu_init(void) register_syscore_ops(&ledtrig_cpu_syscore_ops); - /* - * FIXME: Why needs this to happen in the interrupt disabled - * low level bringup phase of a cpu? - */ - cpuhp_setup_state(CPUHP_AP_LEDTRIG_STARTING, "AP_LEDTRIG_STARTING", - ledtrig_starting_cpu, ledtrig_dying_cpu); + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "AP_LEDTRIG_STARTING", + ledtrig_online_cpu, ledtrig_prepare_down_cpu); + if (ret < 0) + pr_err("CPU hotplug notifier for ledtrig-cpu could not be registered: %d\n", + ret); pr_info("ledtrig-cpu: registered to indicate activity on CPUs\n"); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 09ef54bcba39..282800b42627 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -65,7 +65,6 @@ enum cpuhp_state { CPUHP_AP_ARM_CORESIGHT_STARTING, CPUHP_AP_ARM_CORESIGHT4_STARTING, CPUHP_AP_ARM64_ISNDEP_STARTING, - CPUHP_AP_LEDTRIG_STARTING, CPUHP_AP_SMPCFD_DYING, CPUHP_AP_X86_TBOOT_DYING, CPUHP_AP_NOTIFY_STARTING, -- 2.8.1
