Requests that got stuck in a block driver are neither on blk_mq_ctx.rq_list nor on any hw dispatch queue. Make these visible in debugfs through the "busy" attribute.
Signed-off-by: Bart Van Assche <[email protected]> Cc: Omar Sandoval <[email protected]> Cc: Hannes Reinecke <[email protected]> --- block/blk-mq-debugfs.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 5092d90e37f6..a5e286e04569 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -428,6 +428,43 @@ static const struct file_operations hctx_dispatch_fops = { .release = seq_release, }; +struct show_busy_ctx { + struct seq_file *m; + struct blk_mq_hw_ctx *hctx; +}; + +static void hctx_show_busy(struct request *rq, void *data, bool reserved) +{ + const struct show_busy_ctx *ctx = data; + struct request_queue *q = rq->q; + + if (q->queue_hw_ctx[rq->mq_ctx->index_hw] == ctx->hctx && + test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) + blk_mq_debugfs_rq_show(ctx->m, &rq->queuelist); +} + +static int hctx_busy_show(struct seq_file *m, void *v) +{ + struct blk_mq_hw_ctx *hctx = m->private; + struct show_busy_ctx ctx = { .m = m, .hctx = hctx }; + + blk_mq_tagset_busy_iter(hctx->queue->tag_set, hctx_show_busy, &ctx); + + return 0; +} + +static int hctx_busy_open(struct inode *inode, struct file *file) +{ + return single_open(file, hctx_busy_show, inode->i_private); +} + +static const struct file_operations hctx_busy_fops = { + .open = hctx_busy_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + static int hctx_ctx_map_show(struct seq_file *m, void *v) { struct blk_mq_hw_ctx *hctx = m->private; @@ -885,6 +922,7 @@ static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = { {"state", 0400, &hctx_state_fops}, {"flags", 0400, &hctx_flags_fops}, {"dispatch", 0400, &hctx_dispatch_fops}, + {"busy", 0400, &hctx_busy_fops}, {"ctx_map", 0400, &hctx_ctx_map_fops}, {"tags", 0400, &hctx_tags_fops}, {"tags_bitmap", 0400, &hctx_tags_bitmap_fops}, -- 2.12.2
