diff options
Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0180-block-mq-don-t-complete-requests-via-IPI.patch | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/debian/patches-rt/0180-block-mq-don-t-complete-requests-via-IPI.patch b/debian/patches-rt/0180-block-mq-don-t-complete-requests-via-IPI.patch new file mode 100644 index 000000000..b29ad2ead --- /dev/null +++ b/debian/patches-rt/0180-block-mq-don-t-complete-requests-via-IPI.patch @@ -0,0 +1,119 @@ +From 229760413c4138a40587def4f9420bdb432fa502 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Thu, 29 Jan 2015 15:10:08 +0100 +Subject: [PATCH 180/347] block/mq: don't complete requests via IPI +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +The IPI runs in hardirq context and there are sleeping locks. This patch +moves the completion into a workqueue. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + block/blk-core.c | 3 +++ + block/blk-mq.c | 23 +++++++++++++++++++++++ + include/linux/blk-mq.h | 2 +- + include/linux/blkdev.h | 3 +++ + 4 files changed, 30 insertions(+), 1 deletion(-) + +diff --git a/block/blk-core.c b/block/blk-core.c +index 80f3e729fdd4..461a93c08c14 100644 +--- a/block/blk-core.c ++++ b/block/blk-core.c +@@ -189,6 +189,9 @@ void blk_rq_init(struct request_queue *q, struct request *rq) + + INIT_LIST_HEAD(&rq->queuelist); + INIT_LIST_HEAD(&rq->timeout_list); ++#ifdef CONFIG_PREEMPT_RT_FULL ++ INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); ++#endif + rq->cpu = -1; + rq->q = q; + rq->__sector = (sector_t) -1; +diff --git a/block/blk-mq.c b/block/blk-mq.c +index ea41d67e4db5..0f8dcb68b8a8 100644 +--- a/block/blk-mq.c ++++ b/block/blk-mq.c +@@ -320,6 +320,9 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, + rq->extra_len = 0; + rq->__deadline = 0; + ++#ifdef CONFIG_PREEMPT_RT_FULL ++ INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); ++#endif + INIT_LIST_HEAD(&rq->timeout_list); + rq->timeout = 0; + +@@ -547,12 +550,24 @@ void blk_mq_end_request(struct request *rq, blk_status_t error) + } + EXPORT_SYMBOL(blk_mq_end_request); + ++#ifdef CONFIG_PREEMPT_RT_FULL ++ ++void __blk_mq_complete_request_remote_work(struct work_struct *work) ++{ ++ struct request *rq = container_of(work, struct request, work); ++ ++ rq->q->softirq_done_fn(rq); ++} ++ ++#else ++ + static void __blk_mq_complete_request_remote(void *data) + { + struct request *rq = data; + + rq->q->softirq_done_fn(rq); + } ++#endif + + static void __blk_mq_complete_request(struct request *rq) + { +@@ -575,10 +590,18 @@ static void __blk_mq_complete_request(struct request *rq) + shared = cpus_share_cache(cpu, ctx->cpu); + + if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { ++#ifdef CONFIG_PREEMPT_RT_FULL ++ /* ++ * We could force QUEUE_FLAG_SAME_FORCE then we would not get in ++ * here. But we could try to invoke it one the CPU like this. ++ */ ++ schedule_work_on(ctx->cpu, &rq->work); ++#else + rq->csd.func = __blk_mq_complete_request_remote; + rq->csd.info = rq; + rq->csd.flags = 0; + smp_call_function_single_async(ctx->cpu, &rq->csd); ++#endif + } else { + rq->q->softirq_done_fn(rq); + } +diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h +index 2885dce1ad49..8dbb9ecf9993 100644 +--- a/include/linux/blk-mq.h ++++ b/include/linux/blk-mq.h +@@ -256,7 +256,7 @@ static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag) + return unique_tag & BLK_MQ_UNIQUE_TAG_MASK; + } + +- ++void __blk_mq_complete_request_remote_work(struct work_struct *work); + int blk_mq_request_started(struct request *rq); + void blk_mq_start_request(struct request *rq); + void blk_mq_end_request(struct request *rq, blk_status_t error); +diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h +index 56fe682d9beb..39d90bf9b5fa 100644 +--- a/include/linux/blkdev.h ++++ b/include/linux/blkdev.h +@@ -157,6 +157,9 @@ enum mq_rq_state { + */ + struct request { + struct request_queue *q; ++#ifdef CONFIG_PREEMPT_RT_FULL ++ struct work_struct work; ++#endif + struct blk_mq_ctx *mq_ctx; + + int cpu; +-- +2.36.1 + |