From ed9e1982347b36573cd622ee5f4e2a7ccd79b3fd Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 25 Aug 2008 19:56:05 +0900 Subject: block: implement and use {disk|part}_to_dev() Implement {disk|part}_to_dev() and use them to access generic device instead of directly dereferencing {disk|part}->dev. To make sure no user is left behind, rename generic devices fields to __dev. This is in preparation of unifying partition 0 handling with other partitions. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-sysfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'block/blk-sysfs.c') diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 304ec73ab821..b9a6ed166649 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -310,7 +310,7 @@ int blk_register_queue(struct gendisk *disk) if (!q->request_fn) return 0; - ret = kobject_add(&q->kobj, kobject_get(&disk->dev.kobj), + ret = kobject_add(&q->kobj, kobject_get(&disk_to_dev(disk)->kobj), "%s", "queue"); if (ret < 0) return ret; @@ -339,6 +339,6 @@ void blk_unregister_queue(struct gendisk *disk) kobject_uevent(&q->kobj, KOBJ_REMOVE); kobject_del(&q->kobj); - kobject_put(&disk->dev.kobj); + kobject_put(&disk_to_dev(disk)->kobj); } } -- cgit v1.2.3 From c7c22e4d5c1fdebfac4dba76de7d0338c2b0d832 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 13 Sep 2008 20:26:01 +0200 Subject: block: add support for IO CPU affinity This patch adds support for controlling the IO completion CPU of either all requests on a queue, or on a per-request basis. We export a sysfs variable (rq_affinity) which, if set, migrates completions of requests to the CPU that originally submitted it. A bio helper (bio_set_completion_cpu()) is also added, so that queuers can ask for completion on that specific CPU. In testing, this has been show to cut the system time by as much as 20-40% on synthetic workloads where CPU affinity is desired. This requires a little help from the architecture, so it'll only work as designed for archs that are using the new generic smp helper infrastructure. Signed-off-by: Jens Axboe --- block/blk-sysfs.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'block/blk-sysfs.c') diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index b9a6ed166649..21e275d7eed9 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -156,6 +156,30 @@ static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, return ret; } +static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) +{ + unsigned int set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); + + return queue_var_show(set != 0, page); +} + +static ssize_t +queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) +{ + ssize_t ret = -EINVAL; +#if defined(CONFIG_USE_GENERIC_SMP_HELPERS) + unsigned long val; + + ret = queue_var_store(&val, page, count); + spin_lock_irq(q->queue_lock); + if (val) + queue_flag_set(QUEUE_FLAG_SAME_COMP, q); + else + queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); + spin_unlock_irq(q->queue_lock); +#endif + return ret; +} static struct queue_sysfs_entry queue_requests_entry = { .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR }, @@ -197,6 +221,12 @@ static struct queue_sysfs_entry queue_nomerges_entry = { .store = queue_nomerges_store, }; +static struct queue_sysfs_entry queue_rq_affinity_entry = { + .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR }, + .show = queue_rq_affinity_show, + .store = queue_rq_affinity_store, +}; + static struct attribute *default_attrs[] = { &queue_requests_entry.attr, &queue_ra_entry.attr, @@ -205,6 +235,7 @@ static struct attribute *default_attrs[] = { &queue_iosched_entry.attr, &queue_hw_sector_size_entry.attr, &queue_nomerges_entry.attr, + &queue_rq_affinity_entry.attr, NULL, }; -- cgit v1.2.3