hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I4R7RE CVE: NA
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blkio subsytem is not under default hierarchy in cgroup v1 by default, which means configurations will only be effective on current cgroup for io throttle.
This patch introduces a new feature that enable default hierarchy for io throttle, which means configurations will be effective on child cgroups. Such feature is disabled by default, and can be enabled by:
1) set CONFIG_BLK_DEV_SUPPORT_LEGACY_GLOBAL_LIMIT, then 2) adding "blkcg_global_limit=1" or "blkcg_global_limit=Y" or "blkcg_global_limit=y" in boot cmd;
Signed-off-by: Yu Kuai yukuai3@huawei.com --- block/Kconfig | 11 +++++++++++ block/blk-throttle.c | 26 +++++++++++++++++++++++++- 2 files changed, 36 insertions(+), 1 deletion(-)
diff --git a/block/Kconfig b/block/Kconfig index f1364d1c0d93..95378563a05a 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -111,6 +111,17 @@ config BLK_DEV_THROTTLING_LOW
Note, this is an experimental interface and could be changed someday.
+config BLK_DEV_SUPPORT_LEGACY_GLOBAL_LIMIT + bool "Block layer global limit in cgroup v1" + depends on BLK_DEV_THROTTLING + default n + help + Blkio subsytem is not under default hierarchy in cgroup v1 by default, + enabling this will support globlal limit in cgroup v1. + + Note, a cmdline "blkcg_global_limit=1" is still required to enabled this + feature. + config BLK_WBT bool "Enable support for block device writeback throttling" help diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 13e4377a8b28..3a03cb4a1866 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -41,6 +41,29 @@ /* A workqueue to queue throttle related work */ static struct workqueue_struct *kthrotld_workqueue;
+#ifdef CONFIG_BLK_DEV_SUPPORT_LEGACY_GLOBAL_LIMIT +/* True if global limit is enabled in cgroup v1 */ +static bool global_limit; + +static inline bool blkcg_global_limit_enabled(void) +{ + return global_limit; +} + +static int __init setup_global_limit(char *str) +{ + if (!strcmp(str, "1") || !strcmp(str, "Y") || !strcmp(str, "y")) + global_limit = true; + + return 1; +} + +__setup("blkcg_global_limit=", setup_global_limit); + +#else +static inline bool blkcg_global_limit_enabled(void) + return false; +#endif #define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node)
/* We measure latency for request size from <= 4k to >= 1M */ @@ -405,7 +428,8 @@ static void throtl_pd_init(struct blkg_policy_data *pd) * regardless of the position of the group in the hierarchy. */ sq->parent_sq = &td->service_queue; - if (cgroup_subsys_on_dfl(io_cgrp_subsys) && blkg->parent) + if ((cgroup_subsys_on_dfl(io_cgrp_subsys) || + blkcg_global_limit_enabled()) && blkg->parent) sq->parent_sq = &blkg_to_tg(blkg->parent)->service_queue; tg->td = td; }