Call led_blink_set_oneshot() in RCU critical section to ensure that LED doesn't disappear. (See synchronize_rcu() call in blk_ledtrig_deactivate()). Signed-off-by: Ian Pilcher <arequipeno@gmail.com> --- block/blk-ledtrig.c | 26 ++++++++++++++++++++++++++ block/blk-ledtrig.h | 9 +++++++++ block/blk-mq.c | 2 ++ 3 files changed, 37 insertions(+) diff --git a/block/blk-ledtrig.c b/block/blk-ledtrig.c index 14b1d33a2953..10588f3dea15 100644 --- a/block/blk-ledtrig.c +++ b/block/blk-ledtrig.c @@ -6,6 +6,7 @@ * Copyright 2021 Ian Pilcher <arequipeno@gmail.com> */ +#include <linux/blkdev.h> #include <linux/ctype.h> #include <linux/genhd.h> #include <linux/leds.h> @@ -441,3 +442,28 @@ static int __init blk_ledtrig_init(void) return led_trigger_register(&blk_ledtrig_trigger); } device_initcall(blk_ledtrig_init); + + +/* + * + * Blink the LED associated with a (non-NULL) disk (if set) + * + */ + +void __blk_ledtrig_try_blink(struct request *const rq) +{ + struct blk_ledtrig_led *bd_led; + unsigned long delay_on, delay_off; + + rcu_read_lock(); + + bd_led = rcu_dereference(rq->rq_disk->led); + + if (bd_led != NULL) { + delay_on = READ_ONCE(bd_led->blink_on); + delay_off = READ_ONCE(bd_led->blink_off); + led_blink_set_oneshot(bd_led->led, &delay_on, &delay_off, 0); + } + + rcu_read_unlock(); +} diff --git a/block/blk-ledtrig.h b/block/blk-ledtrig.h index 771000d43647..7eb1d88e2b3c 100644 --- a/block/blk-ledtrig.h +++ b/block/blk-ledtrig.h @@ -26,10 +26,19 @@ ssize_t blk_ledtrig_dev_led_show(struct device *const dev, struct device_attribute *const attr, char *const buf); +void __blk_ledtrig_try_blink(struct request *const rq); + +static inline void blk_ledtrig_try_blink(struct request *const rq) +{ + if (rq->rq_disk != NULL) + __blk_ledtrig_try_blink(rq); +} + #else // CONFIG_BLK_LED_TRIGGERS static inline void blk_ledtrig_disk_init(const struct gendisk *disk) {} static inline void blk_ledtrig_dev_clear(const struct gendisk *disk) {} +static inline void blk_ledtrig_try_blink(const struct request *rq) {} #endif // CONFIG_BLK_LED_TRIGGERS diff --git a/block/blk-mq.c b/block/blk-mq.c index 2c4ac51e54eb..7732e31f3ca8 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -40,6 +40,7 @@ #include "blk-stat.h" #include "blk-mq-sched.h" #include "blk-rq-qos.h" +#include "blk-ledtrig.h" static DEFINE_PER_CPU(struct llist_head, blk_cpu_done); @@ -1381,6 +1382,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, switch (ret) { case BLK_STS_OK: queued++; + blk_ledtrig_try_blink(rq); break; case BLK_STS_RESOURCE: case BLK_STS_DEV_RESOURCE: -- 2.31.1