From 645a829e03384a235b3760959d4ebe420a0f2027 Mon Sep 17 00:00:00 2001 From: Yu Kuai Date: Sat, 27 May 2023 09:06:40 +0800 Subject: blk-wbt: don't create wbt sysfs entry if CONFIG_BLK_WBT is disabled sysfs entry /sys/block/[device]/queue/wbt_lat_usec will be created even if CONFIG_BLK_WBT is disabled, while read and write will always fail. It doesn't make sense to create a sysfs entry that can't be accessed, so don't create such entry. Signed-off-by: Yu Kuai Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230527010644.647900-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe --- block/blk-sysfs.c | 143 ++++++++++++++++++++++++++++-------------------------- block/blk-wbt.h | 19 -------- 2 files changed, 74 insertions(+), 88 deletions(-) (limited to 'block') diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index a64208583853..6c1c4ba66bc0 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -47,19 +47,6 @@ queue_var_store(unsigned long *var, const char *page, size_t count) return count; } -static ssize_t queue_var_store64(s64 *var, const char *page) -{ - int err; - s64 v; - - err = kstrtos64(page, 10, &v); - if (err < 0) - return err; - - *var = v; - return 0; -} - static ssize_t queue_requests_show(struct request_queue *q, char *page) { return queue_var_show(q->nr_requests, page); @@ -451,61 +438,6 @@ static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, return count; } -static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) -{ - if (!wbt_rq_qos(q)) - return -EINVAL; - - if (wbt_disabled(q)) - return sprintf(page, "0\n"); - - return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); -} - -static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, - size_t count) -{ - struct rq_qos *rqos; - ssize_t ret; - s64 val; - - ret = queue_var_store64(&val, page); - if (ret < 0) - return ret; - if (val < -1) - return -EINVAL; - - rqos = wbt_rq_qos(q); - if (!rqos) { - ret = wbt_init(q->disk); - if (ret) - return ret; - } - - if (val == -1) - val = wbt_default_latency_nsec(q); - else if (val >= 0) - val *= 1000ULL; - - if (wbt_get_min_lat(q) == val) - return count; - - /* - * Ensure that the queue is idled, in case the latency update - * ends up either enabling or disabling wbt completely. We can't - * have IO inflight if that happens. - */ - blk_mq_freeze_queue(q); - blk_mq_quiesce_queue(q); - - wbt_set_min_lat(q, val); - - blk_mq_unquiesce_queue(q); - blk_mq_unfreeze_queue(q); - - return count; -} - static ssize_t queue_wc_show(struct request_queue *q, char *page) { if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) @@ -598,7 +530,6 @@ QUEUE_RW_ENTRY(queue_wc, "write_cache"); QUEUE_RO_ENTRY(queue_fua, "fua"); QUEUE_RO_ENTRY(queue_dax, "dax"); QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); -QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); @@ -617,6 +548,78 @@ QUEUE_RW_ENTRY(queue_iostats, "iostats"); QUEUE_RW_ENTRY(queue_random, "add_random"); QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); +#ifdef CONFIG_BLK_WBT +static ssize_t queue_var_store64(s64 *var, const char *page) +{ + int err; + s64 v; + + err = kstrtos64(page, 10, &v); + if (err < 0) + return err; + + *var = v; + return 0; +} + +static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) +{ + if (!wbt_rq_qos(q)) + return -EINVAL; + + if (wbt_disabled(q)) + return sprintf(page, "0\n"); + + return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); +} + +static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, + size_t count) +{ + struct rq_qos *rqos; + ssize_t ret; + s64 val; + + ret = queue_var_store64(&val, page); + if (ret < 0) + return ret; + if (val < -1) + return -EINVAL; + + rqos = wbt_rq_qos(q); + if (!rqos) { + ret = wbt_init(q->disk); + if (ret) + return ret; + } + + if (val == -1) + val = wbt_default_latency_nsec(q); + else if (val >= 0) + val *= 1000ULL; + + if (wbt_get_min_lat(q) == val) + return count; + + /* + * Ensure that the queue is idled, in case the latency update + * ends up either enabling or disabling wbt completely. We can't + * have IO inflight if that happens. + */ + blk_mq_freeze_queue(q); + blk_mq_quiesce_queue(q); + + wbt_set_min_lat(q, val); + + blk_mq_unquiesce_queue(q); + blk_mq_unfreeze_queue(q); + + return count; +} + +QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); +#endif + static struct attribute *queue_attrs[] = { &queue_requests_entry.attr, &queue_ra_entry.attr, @@ -655,7 +658,9 @@ static struct attribute *queue_attrs[] = { &queue_wc_entry.attr, &queue_fua_entry.attr, &queue_dax_entry.attr, +#ifdef CONFIG_BLK_WBT &queue_wb_lat_entry.attr, +#endif &queue_poll_delay_entry.attr, &queue_io_timeout_entry.attr, #ifdef CONFIG_BLK_DEV_THROTTLING_LOW diff --git a/block/blk-wbt.h b/block/blk-wbt.h index ba6cca5849a6..8a029e138f7a 100644 --- a/block/blk-wbt.h +++ b/block/blk-wbt.h @@ -18,10 +18,6 @@ u64 wbt_default_latency_nsec(struct request_queue *); #else -static inline int wbt_init(struct gendisk *disk) -{ - return -EINVAL; -} static inline void wbt_disable_default(struct gendisk *disk) { } @@ -31,21 +27,6 @@ static inline void wbt_enable_default(struct gendisk *disk) static inline void wbt_set_write_cache(struct request_queue *q, bool wc) { } -static inline u64 wbt_get_min_lat(struct request_queue *q) -{ - return 0; -} -static inline void wbt_set_min_lat(struct request_queue *q, u64 val) -{ -} -static inline u64 wbt_default_latency_nsec(struct request_queue *q) -{ - return 0; -} -static inline bool wbt_disabled(struct request_queue *q) -{ - return true; -} #endif /* CONFIG_BLK_WBT */ -- cgit