Re: [PATCH 5/6] blk-mq-debugfs: Show busy requests
On Mon, 2017-05-01 at 17:17 -0700, Omar Sandoval wrote: > On Thu, Apr 27, 2017 at 08:54:36AM -0700, Bart Van Assche wrote: > > + if (q->queue_hw_ctx[rq->mq_ctx->index_hw] == ctx->hctx && > > This doesn't look right. ctx->index_hw is the index into hctx->ctxs for > this ctx. I think you mean blk_mq_map_queue(q, rq->mq_ctx->cpu). Hello Omar, Thanks for the feedback. I will integrate this fix when I repost this patch series (after the merge window has closed). Bart.
Re: [PATCH 5/6] blk-mq-debugfs: Show busy requests
On Thu, Apr 27, 2017 at 08:54:36AM -0700, Bart Van Assche wrote: > 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> Cc: Omar Sandoval > Cc: Hannes Reinecke > --- > 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 && This doesn't look right. ctx->index_hw is the index into hctx->ctxs for this ctx. I think you mean blk_mq_map_queue(q, rq->mq_ctx->cpu). > + test_bit(REQ_ATOM_STARTED, >atomic_flags)) > + blk_mq_debugfs_rq_show(ctx->m, >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, ); > + > + 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, _state_fops}, > {"flags", 0400, _flags_fops}, > {"dispatch", 0400, _dispatch_fops}, > + {"busy", 0400, _busy_fops}, > {"ctx_map", 0400, _ctx_map_fops}, > {"tags", 0400, _tags_fops}, > {"tags_bitmap", 0400, _tags_bitmap_fops}, > -- > 2.12.2 >
[PATCH 5/6] blk-mq-debugfs: Show busy requests
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 AsscheCc: Omar Sandoval Cc: Hannes Reinecke --- 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, >atomic_flags)) + blk_mq_debugfs_rq_show(ctx->m, >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, ); + + 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, _state_fops}, {"flags", 0400, _flags_fops}, {"dispatch", 0400, _dispatch_fops}, + {"busy", 0400, _busy_fops}, {"ctx_map", 0400, _ctx_map_fops}, {"tags", 0400, _tags_fops}, {"tags_bitmap", 0400, _tags_bitmap_fops}, -- 2.12.2