From 950cd7e9ffdc44c340b8914126b39cc079f0c844 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Wed, 25 Jan 2017 08:06:42 -0800 Subject: [PATCH] blk-mq: move hctx->dispatch and ctx->rq_list from sysfs to debugfs These lists are only useful for debugging; they definitely don't belong in sysfs. Putting them in debugfs also removes the limitation of a single page of output. Reviewed-by: Hannes Reinecke Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe --- block/blk-mq-debugfs.c | 106 +++++++++++++++++++++++++++++++++++++++++ block/blk-mq-sysfs.c | 57 ---------------------- 2 files changed, 106 insertions(+), 57 deletions(-) diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 0c14511fa9e0..1967c06d80e0 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -29,6 +29,20 @@ struct blk_mq_debugfs_attr { static struct dentry *block_debugfs_root; +static int blk_mq_debugfs_seq_open(struct inode *inode, struct file *file, + const struct seq_operations *ops) +{ + struct seq_file *m; + int ret; + + ret = seq_open(file, ops); + if (!ret) { + m = file->private_data; + m->private = inode->i_private; + } + return ret; +} + static int hctx_state_show(struct seq_file *m, void *v) { struct blk_mq_hw_ctx *hctx = m->private; @@ -69,12 +83,104 @@ static const struct file_operations hctx_flags_fops = { .release = single_release, }; +static int blk_mq_debugfs_rq_show(struct seq_file *m, void *v) +{ + struct request *rq = list_entry_rq(v); + + seq_printf(m, "%p\n", rq); + return 0; +} + +static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos) +{ + struct blk_mq_hw_ctx *hctx = m->private; + + spin_lock(&hctx->lock); + return seq_list_start(&hctx->dispatch, *pos); +} + +static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct blk_mq_hw_ctx *hctx = m->private; + + return seq_list_next(v, &hctx->dispatch, pos); +} + +static void hctx_dispatch_stop(struct seq_file *m, void *v) +{ + struct blk_mq_hw_ctx *hctx = m->private; + + spin_unlock(&hctx->lock); +} + +static const struct seq_operations hctx_dispatch_seq_ops = { + .start = hctx_dispatch_start, + .next = hctx_dispatch_next, + .stop = hctx_dispatch_stop, + .show = blk_mq_debugfs_rq_show, +}; + +static int hctx_dispatch_open(struct inode *inode, struct file *file) +{ + return blk_mq_debugfs_seq_open(inode, file, &hctx_dispatch_seq_ops); +} + +static const struct file_operations hctx_dispatch_fops = { + .open = hctx_dispatch_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static void *ctx_rq_list_start(struct seq_file *m, loff_t *pos) +{ + struct blk_mq_ctx *ctx = m->private; + + spin_lock(&ctx->lock); + return seq_list_start(&ctx->rq_list, *pos); +} + +static void *ctx_rq_list_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct blk_mq_ctx *ctx = m->private; + + return seq_list_next(v, &ctx->rq_list, pos); +} + +static void ctx_rq_list_stop(struct seq_file *m, void *v) +{ + struct blk_mq_ctx *ctx = m->private; + + spin_unlock(&ctx->lock); +} + +static const struct seq_operations ctx_rq_list_seq_ops = { + .start = ctx_rq_list_start, + .next = ctx_rq_list_next, + .stop = ctx_rq_list_stop, + .show = blk_mq_debugfs_rq_show, +}; + +static int ctx_rq_list_open(struct inode *inode, struct file *file) +{ + return blk_mq_debugfs_seq_open(inode, file, &ctx_rq_list_seq_ops); +} + +static const struct file_operations ctx_rq_list_fops = { + .open = ctx_rq_list_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + 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}, }; static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = { + {"rq_list", 0400, &ctx_rq_list_fops}, }; int blk_mq_debugfs_register(struct request_queue *q, const char *name) diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c index 91b93ca1c1e0..ee3694d8c4ee 100644 --- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -139,41 +139,6 @@ static ssize_t blk_mq_sysfs_completed_show(struct blk_mq_ctx *ctx, char *page) ctx->rq_completed[0]); } -static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg) -{ - struct request *rq; - int len = snprintf(page, PAGE_SIZE - 1, "%s:\n", msg); - - list_for_each_entry(rq, list, queuelist) { - const int rq_len = 2 * sizeof(rq) + 2; - - /* if the output will be truncated */ - if (PAGE_SIZE - 1 < len + rq_len) { - /* backspacing if it can't hold '\t...\n' */ - if (PAGE_SIZE - 1 < len + 5) - len -= rq_len; - len += snprintf(page + len, PAGE_SIZE - 1 - len, - "\t...\n"); - break; - } - len += snprintf(page + len, PAGE_SIZE - 1 - len, - "\t%p\n", rq); - } - - return len; -} - -static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page) -{ - ssize_t ret; - - spin_lock(&ctx->lock); - ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending"); - spin_unlock(&ctx->lock); - - return ret; -} - static ssize_t blk_mq_hw_sysfs_poll_show(struct blk_mq_hw_ctx *hctx, char *page) { return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n", @@ -219,18 +184,6 @@ static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx, return page - start_page; } -static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx, - char *page) -{ - ssize_t ret; - - spin_lock(&hctx->lock); - ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending"); - spin_unlock(&hctx->lock); - - return ret; -} - static ssize_t blk_mq_hw_sysfs_sched_tags_show(struct blk_mq_hw_ctx *hctx, char *page) { if (hctx->sched_tags) @@ -320,16 +273,11 @@ static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = { .attr = {.name = "completed", .mode = S_IRUGO }, .show = blk_mq_sysfs_completed_show, }; -static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = { - .attr = {.name = "rq_list", .mode = S_IRUGO }, - .show = blk_mq_sysfs_rq_list_show, -}; static struct attribute *default_ctx_attrs[] = { &blk_mq_sysfs_dispatched.attr, &blk_mq_sysfs_merged.attr, &blk_mq_sysfs_completed.attr, - &blk_mq_sysfs_rq_list.attr, NULL, }; @@ -349,10 +297,6 @@ static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = { .attr = {.name = "active", .mode = S_IRUGO }, .show = blk_mq_hw_sysfs_active_show, }; -static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = { - .attr = {.name = "pending", .mode = S_IRUGO }, - .show = blk_mq_hw_sysfs_rq_list_show, -}; static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_sched_tags = { .attr = {.name = "sched_tags", .mode = S_IRUGO }, .show = blk_mq_hw_sysfs_sched_tags_show, @@ -380,7 +324,6 @@ static struct attribute *default_hw_ctx_attrs[] = { &blk_mq_hw_sysfs_queued.attr, &blk_mq_hw_sysfs_run.attr, &blk_mq_hw_sysfs_dispatched.attr, - &blk_mq_hw_sysfs_pending.attr, &blk_mq_hw_sysfs_tags.attr, &blk_mq_hw_sysfs_sched_tags.attr, &blk_mq_hw_sysfs_cpus.attr, -- 2.30.2