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| author | Shaohua Li <shli@kernel.org> | 2013-08-27 17:50:42 +0800 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2013-08-28 16:56:52 +1000 |
| commit | b721420e8719131896b009b11edbbd27d9b85e98 (patch) | |
| tree | cb1cfdc9d63150365da8f47d283209401836d0fc | |
| parent | 851c30c9badfc6b294c98e887624bff53644ad21 (diff) | |
| download | blackbird-obmc-linux-b721420e8719131896b009b11edbbd27d9b85e98.tar.gz blackbird-obmc-linux-b721420e8719131896b009b11edbbd27d9b85e98.zip | |
raid5: sysfs entry to control worker thread number
Add a sysfs entry to control running workqueue thread number. If
group_thread_cnt is set to 0, we will disable workqueue offload handling of
stripes.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
| -rw-r--r-- | drivers/md/raid5.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 32fa1131cafc..d79ecd903269 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5145,10 +5145,70 @@ stripe_cache_active_show(struct mddev *mddev, char *page) static struct md_sysfs_entry raid5_stripecache_active = __ATTR_RO(stripe_cache_active); +static ssize_t +raid5_show_group_thread_cnt(struct mddev *mddev, char *page) +{ + struct r5conf *conf = mddev->private; + if (conf) + return sprintf(page, "%d\n", conf->worker_cnt_per_group); + else + return 0; +} + +static int alloc_thread_groups(struct r5conf *conf, int cnt); +static ssize_t +raid5_store_group_thread_cnt(struct mddev *mddev, const char *page, size_t len) +{ + struct r5conf *conf = mddev->private; + unsigned long new; + int err; + struct r5worker_group *old_groups; + int old_group_cnt; + + if (len >= PAGE_SIZE) + return -EINVAL; + if (!conf) + return -ENODEV; + + if (kstrtoul(page, 10, &new)) + return -EINVAL; + + if (new == conf->worker_cnt_per_group) + return len; + + mddev_suspend(mddev); + + old_groups = conf->worker_groups; + old_group_cnt = conf->worker_cnt_per_group; + + conf->worker_groups = NULL; + err = alloc_thread_groups(conf, new); + if (err) { + conf->worker_groups = old_groups; + conf->worker_cnt_per_group = old_group_cnt; + } else { + if (old_groups) + kfree(old_groups[0].workers); + kfree(old_groups); + } + + mddev_resume(mddev); + + if (err) + return err; + return len; +} + +static struct md_sysfs_entry +raid5_group_thread_cnt = __ATTR(group_thread_cnt, S_IRUGO | S_IWUSR, + raid5_show_group_thread_cnt, + raid5_store_group_thread_cnt); + static struct attribute *raid5_attrs[] = { &raid5_stripecache_size.attr, &raid5_stripecache_active.attr, &raid5_preread_bypass_threshold.attr, + &raid5_group_thread_cnt.attr, NULL, }; static struct attribute_group raid5_attrs_group = { |
