From 66088084fdabb6e5075cd19e8ffe15b8bc7e3708 Mon Sep 17 00:00:00 2001 From: John Garry Date: Fri, 14 Jun 2024 09:03:45 +0000 Subject: [PATCH] block: BFQ: Refactor bfq_exit_icq() to silence sparse warning Currently building for C=1 generates the following warning: block/bfq-iosched.c:5498:9: warning: context imbalance in 'bfq_exit_icq' - different lock contexts for basic block Refactor bfq_exit_icq() into a core part which loops for the actuators, and only lock calling this routine when necessary. Signed-off-by: John Garry Reviewed-by: Bart Van Assche Link: https://lore.kernel.org/r/20240614090345.655716-4-john.g.garry@oracle.com Signed-off-by: Jens Axboe --- block/bfq-iosched.c | 46 +++++++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 22 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 4b88a54a9b76..36a4998c4b37 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -5463,29 +5463,10 @@ static void bfq_exit_icq_bfqq(struct bfq_io_cq *bic, bool is_sync, } } -static void bfq_exit_icq(struct io_cq *icq) +static void _bfq_exit_icq(struct bfq_io_cq *bic, unsigned int num_actuators) { - struct bfq_io_cq *bic = icq_to_bic(icq); - struct bfq_data *bfqd = bic_to_bfqd(bic); - unsigned long flags; - unsigned int act_idx; - /* - * If bfqd and thus bfqd->num_actuators is not available any - * longer, then cycle over all possible per-actuator bfqqs in - * next loop. We rely on bic being zeroed on creation, and - * therefore on its unused per-actuator fields being NULL. - */ - unsigned int num_actuators = BFQ_MAX_ACTUATORS; struct bfq_iocq_bfqq_data *bfqq_data = bic->bfqq_data; - - /* - * bfqd is NULL if scheduler already exited, and in that case - * this is the last time these queues are accessed. - */ - if (bfqd) { - spin_lock_irqsave(&bfqd->lock, flags); - num_actuators = bfqd->num_actuators; - } + unsigned int act_idx; for (act_idx = 0; act_idx < num_actuators; act_idx++) { if (bfqq_data[act_idx].stable_merge_bfqq) @@ -5494,9 +5475,30 @@ static void bfq_exit_icq(struct io_cq *icq) bfq_exit_icq_bfqq(bic, true, act_idx); bfq_exit_icq_bfqq(bic, false, act_idx); } +} - if (bfqd) +static void bfq_exit_icq(struct io_cq *icq) +{ + struct bfq_io_cq *bic = icq_to_bic(icq); + struct bfq_data *bfqd = bic_to_bfqd(bic); + unsigned long flags; + + /* + * If bfqd and thus bfqd->num_actuators is not available any + * longer, then cycle over all possible per-actuator bfqqs in + * next loop. We rely on bic being zeroed on creation, and + * therefore on its unused per-actuator fields being NULL. + * + * bfqd is NULL if scheduler already exited, and in that case + * this is the last time these queues are accessed. + */ + if (bfqd) { + spin_lock_irqsave(&bfqd->lock, flags); + _bfq_exit_icq(bic, bfqd->num_actuators); spin_unlock_irqrestore(&bfqd->lock, flags); + } else { + _bfq_exit_icq(bic, BFQ_MAX_ACTUATORS); + } } /*