#include <linux/delay.h>
#include <linux/ratelimit.h>
#include <linux/pm_runtime.h>
+#include <linux/blk-cgroup.h>
#define CREATE_TRACE_POINTS
#include <trace/events/block.h>
#include "blk.h"
-#include "blk-cgroup.h"
#include "blk-mq.h"
EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap);
*/
static struct workqueue_struct *kblockd_workqueue;
+static void blk_clear_congested(struct request_list *rl, int sync)
+{
+#ifdef CONFIG_CGROUP_WRITEBACK
+ clear_wb_congested(rl->blkg->wb_congested, sync);
+#else
+ /*
+ * If !CGROUP_WRITEBACK, all blkg's map to bdi->wb and we shouldn't
+ * flip its congestion state for events on other blkcgs.
+ */
+ if (rl == &rl->q->root_rl)
+ clear_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
+#endif
+}
+
+static void blk_set_congested(struct request_list *rl, int sync)
+{
+#ifdef CONFIG_CGROUP_WRITEBACK
+ set_wb_congested(rl->blkg->wb_congested, sync);
+#else
+ /* see blk_clear_congested() */
+ if (rl == &rl->q->root_rl)
+ set_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
+#endif
+}
+
void blk_queue_congestion_threshold(struct request_queue *q)
{
int nr;
static void req_bio_endio(struct request *rq, struct bio *bio,
unsigned int nbytes, int error)
{
- if (error)
+ if (error && !(rq->cmd_flags & REQ_CLONE))
clear_bit(BIO_UPTODATE, &bio->bi_flags);
else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
error = -EIO;
bio_advance(bio, nbytes);
/* don't actually finish bio if it's part of flush sequence */
- if (bio->bi_iter.bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ))
+ if (bio->bi_iter.bi_size == 0 &&
+ !(rq->cmd_flags & (REQ_FLUSH_SEQ|REQ_CLONE)))
bio_endio(bio, error);
}
q->request_fn(q);
q->request_fn_active--;
}
+EXPORT_SYMBOL_GPL(__blk_run_queue_uncond);
/**
* __blk_run_queue - run a single device queue
q->backing_dev_info.ra_pages =
(VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
- q->backing_dev_info.state = 0;
- q->backing_dev_info.capabilities = 0;
+ q->backing_dev_info.capabilities = BDI_CAP_CGROUP_WRITEBACK;
q->backing_dev_info.name = "block";
q->node = node_id;
{
struct request_queue *q = rl->q;
- /*
- * bdi isn't aware of blkcg yet. As all async IOs end up root
- * blkcg anyway, just use root blkcg state.
- */
- if (rl == &q->root_rl &&
- rl->count[sync] < queue_congestion_off_threshold(q))
- blk_clear_queue_congested(q, sync);
+ if (rl->count[sync] < queue_congestion_off_threshold(q))
+ blk_clear_congested(rl, sync);
if (rl->count[sync] + 1 <= q->nr_requests) {
if (waitqueue_active(&rl->wait[sync]))
int blk_update_nr_requests(struct request_queue *q, unsigned int nr)
{
struct request_list *rl;
+ int on_thresh, off_thresh;
spin_lock_irq(q->queue_lock);
q->nr_requests = nr;
blk_queue_congestion_threshold(q);
+ on_thresh = queue_congestion_on_threshold(q);
+ off_thresh = queue_congestion_off_threshold(q);
- /* congestion isn't cgroup aware and follows root blkcg for now */
- rl = &q->root_rl;
-
- if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
- blk_set_queue_congested(q, BLK_RW_SYNC);
- else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
- blk_clear_queue_congested(q, BLK_RW_SYNC);
+ blk_queue_for_each_rl(rl, q) {
+ if (rl->count[BLK_RW_SYNC] >= on_thresh)
+ blk_set_congested(rl, BLK_RW_SYNC);
+ else if (rl->count[BLK_RW_SYNC] < off_thresh)
+ blk_clear_congested(rl, BLK_RW_SYNC);
- if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
- blk_set_queue_congested(q, BLK_RW_ASYNC);
- else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
- blk_clear_queue_congested(q, BLK_RW_ASYNC);
+ if (rl->count[BLK_RW_ASYNC] >= on_thresh)
+ blk_set_congested(rl, BLK_RW_ASYNC);
+ else if (rl->count[BLK_RW_ASYNC] < off_thresh)
+ blk_clear_congested(rl, BLK_RW_ASYNC);
- blk_queue_for_each_rl(rl, q) {
if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
blk_set_rl_full(rl, BLK_RW_SYNC);
} else {
}
}
}
- /*
- * bdi isn't aware of blkcg yet. As all async IOs end up
- * root blkcg anyway, just use root blkcg state.
- */
- if (rl == &q->root_rl)
- blk_set_queue_congested(q, is_sync);
+ blk_set_congested(rl, is_sync);
}
/*
* Caller must ensure !blk_queue_nomerges(q) beforehand.
*/
bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
- unsigned int *request_count)
+ unsigned int *request_count,
+ struct request **same_queue_rq)
{
struct blk_plug *plug;
struct request *rq;
list_for_each_entry_reverse(rq, plug_list, queuelist) {
int el_ret;
- if (rq->q == q)
+ if (rq->q == q) {
(*request_count)++;
+ /*
+ * Only blk-mq multiple hardware queues case checks the
+ * rq in the same queue, there should be only one such
+ * rq in a queue
+ **/
+ if (same_queue_rq)
+ *same_queue_rq = rq;
+ }
if (rq->q != q || !blk_rq_merge_ok(rq, bio))
continue;
* any locks.
*/
if (!blk_queue_nomerges(q) &&
- blk_attempt_plug_merge(q, bio, &request_count))
+ blk_attempt_plug_merge(q, bio, &request_count, NULL))
return;
spin_lock_irq(q->queue_lock);
bio->bi_rw,
(unsigned long long)bio_end_sector(bio),
(long long)(i_size_read(bio->bi_bdev->bd_inode) >> 9));
-
- set_bit(BIO_EOF, &bio->bi_flags);
}
#ifdef CONFIG_FAIL_MAKE_REQUEST
}
EXPORT_SYMBOL_GPL(blk_lld_busy);
-/**
- * blk_rq_unprep_clone - Helper function to free all bios in a cloned request
- * @rq: the clone request to be cleaned up
- *
- * Description:
- * Free all bios in @rq for a cloned request.
- */
-void blk_rq_unprep_clone(struct request *rq)
-{
- struct bio *bio;
-
- while ((bio = rq->bio) != NULL) {
- rq->bio = bio->bi_next;
-
- bio_put(bio);
- }
-}
-EXPORT_SYMBOL_GPL(blk_rq_unprep_clone);
-
-/*
- * Copy attributes of the original request to the clone request.
- * The actual data parts (e.g. ->cmd, ->sense) are not copied.
- */
-static void __blk_rq_prep_clone(struct request *dst, struct request *src)
+void blk_rq_prep_clone(struct request *dst, struct request *src)
{
dst->cpu = src->cpu;
- dst->cmd_flags |= (src->cmd_flags & REQ_CLONE_MASK) | REQ_NOMERGE;
+ dst->cmd_flags |= (src->cmd_flags & REQ_CLONE_MASK);
+ dst->cmd_flags |= REQ_NOMERGE | REQ_CLONE;
dst->cmd_type = src->cmd_type;
dst->__sector = blk_rq_pos(src);
dst->__data_len = blk_rq_bytes(src);
dst->nr_phys_segments = src->nr_phys_segments;
dst->ioprio = src->ioprio;
dst->extra_len = src->extra_len;
-}
-
-/**
- * blk_rq_prep_clone - Helper function to setup clone request
- * @rq: the request to be setup
- * @rq_src: original request to be cloned
- * @bs: bio_set that bios for clone are allocated from
- * @gfp_mask: memory allocation mask for bio
- * @bio_ctr: setup function to be called for each clone bio.
- * Returns %0 for success, non %0 for failure.
- * @data: private data to be passed to @bio_ctr
- *
- * Description:
- * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq.
- * The actual data parts of @rq_src (e.g. ->cmd, ->sense)
- * are not copied, and copying such parts is the caller's responsibility.
- * Also, pages which the original bios are pointing to are not copied
- * and the cloned bios just point same pages.
- * So cloned bios must be completed before original bios, which means
- * the caller must complete @rq before @rq_src.
- */
-int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
- struct bio_set *bs, gfp_t gfp_mask,
- int (*bio_ctr)(struct bio *, struct bio *, void *),
- void *data)
-{
- struct bio *bio, *bio_src;
-
- if (!bs)
- bs = fs_bio_set;
-
- __rq_for_each_bio(bio_src, rq_src) {
- bio = bio_clone_fast(bio_src, gfp_mask, bs);
- if (!bio)
- goto free_and_out;
-
- if (bio_ctr && bio_ctr(bio, bio_src, data))
- goto free_and_out;
-
- if (rq->bio) {
- rq->biotail->bi_next = bio;
- rq->biotail = bio;
- } else
- rq->bio = rq->biotail = bio;
- }
-
- __blk_rq_prep_clone(rq, rq_src);
-
- return 0;
-
-free_and_out:
- if (bio)
- bio_put(bio);
- blk_rq_unprep_clone(rq);
-
- return -ENOMEM;
+ dst->bio = src->bio;
+ dst->biotail = src->biotail;
+ dst->cmd = src->cmd;
+ dst->cmd_len = src->cmd_len;
+ dst->sense = src->sense;
}
EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
{
struct task_struct *tsk = current;
+ /*
+ * If this is a nested plug, don't actually assign it.
+ */
+ if (tsk->plug)
+ return;
+
INIT_LIST_HEAD(&plug->list);
INIT_LIST_HEAD(&plug->mq_list);
INIT_LIST_HEAD(&plug->cb_list);
-
/*
- * If this is a nested plug, don't actually assign it. It will be
- * flushed on its own.
+ * Store ordering should not be needed here, since a potential
+ * preempt will imply a full memory barrier
*/
- if (!tsk->plug) {
- /*
- * Store ordering should not be needed here, since a potential
- * preempt will imply a full memory barrier
- */
- tsk->plug = plug;
- }
+ tsk->plug = plug;
}
EXPORT_SYMBOL(blk_start_plug);
void blk_finish_plug(struct blk_plug *plug)
{
+ if (plug != current->plug)
+ return;
blk_flush_plug_list(plug, false);
- if (plug == current->plug)
- current->plug = NULL;
+ current->plug = NULL;
}
EXPORT_SYMBOL(blk_finish_plug);