From 6a26f9c68901797261bc145975a02f85be0c1d8f Mon Sep 17 00:00:00 2001 From: Xiu Jianfeng Date: Thu, 11 Jul 2024 10:14:57 +0000 Subject: [PATCH] cgroup/misc: Introduce misc.events.local Currently the event counting provided by misc.events is hierarchical, it's not practical if user is only concerned with events of a specified cgroup. Therefore, introduce misc.events.local collect events specific to the given cgroup. This is analogous to memory.events.local and pids.events.local. Signed-off-by: Xiu Jianfeng Signed-off-by: Tejun Heo --- Documentation/admin-guide/cgroup-v2.rst | 5 ++++ include/linux/misc_cgroup.h | 3 ++ kernel/cgroup/misc.c | 39 +++++++++++++++++++++---- 3 files changed, 41 insertions(+), 6 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 52763d6b2919..05862f06ed26 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2680,6 +2680,11 @@ Miscellaneous controller provides 3 interface files. If two misc resources (res_ The number of times the cgroup's resource usage was about to go over the max boundary. + misc.events.local + Similar to misc.events but the fields in the file are local to the + cgroup i.e. not hierarchical. The file modified event generated on + this file reflects only the local events. + Migration and Ownership ~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/include/linux/misc_cgroup.h b/include/linux/misc_cgroup.h index 618392d41975..49eef10c8e59 100644 --- a/include/linux/misc_cgroup.h +++ b/include/linux/misc_cgroup.h @@ -40,6 +40,7 @@ struct misc_res { atomic64_t watermark; atomic64_t usage; atomic64_t events; + atomic64_t events_local; }; /** @@ -53,6 +54,8 @@ struct misc_cg { /* misc.events */ struct cgroup_file events_file; + /* misc.events.local */ + struct cgroup_file events_local_file; struct misc_res res[MISC_CG_RES_TYPES]; }; diff --git a/kernel/cgroup/misc.c b/kernel/cgroup/misc.c index b92daf5d234d..0e26068995a6 100644 --- a/kernel/cgroup/misc.c +++ b/kernel/cgroup/misc.c @@ -134,6 +134,17 @@ static void misc_cg_update_watermark(struct misc_res *res, u64 new_usage) } } +static void misc_cg_event(enum misc_res_type type, struct misc_cg *cg) +{ + atomic64_inc(&cg->res[type].events_local); + cgroup_file_notify(&cg->events_local_file); + + for (; parent_misc(cg); cg = parent_misc(cg)) { + atomic64_inc(&cg->res[type].events); + cgroup_file_notify(&cg->events_file); + } +} + /** * misc_cg_try_charge() - Try charging the misc cgroup. * @type: Misc res type to charge. @@ -177,10 +188,7 @@ int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, u64 amount) return 0; err_charge: - for (j = i; j; j = parent_misc(j)) { - atomic64_inc(&j->res[type].events); - cgroup_file_notify(&j->events_file); - } + misc_cg_event(type, i); for (j = cg; j != i; j = parent_misc(j)) misc_cg_cancel_charge(type, j, amount); @@ -368,20 +376,33 @@ static int misc_cg_capacity_show(struct seq_file *sf, void *v) return 0; } -static int misc_events_show(struct seq_file *sf, void *v) +static int __misc_events_show(struct seq_file *sf, bool local) { struct misc_cg *cg = css_misc(seq_css(sf)); u64 events; int i; for (i = 0; i < MISC_CG_RES_TYPES; i++) { - events = atomic64_read(&cg->res[i].events); + if (local) + events = atomic64_read(&cg->res[i].events_local); + else + events = atomic64_read(&cg->res[i].events); if (READ_ONCE(misc_res_capacity[i]) || events) seq_printf(sf, "%s.max %llu\n", misc_res_name[i], events); } return 0; } +static int misc_events_show(struct seq_file *sf, void *v) +{ + return __misc_events_show(sf, false); +} + +static int misc_events_local_show(struct seq_file *sf, void *v) +{ + return __misc_events_show(sf, true); +} + /* Misc cgroup interface files */ static struct cftype misc_cg_files[] = { { @@ -409,6 +430,12 @@ static struct cftype misc_cg_files[] = { .file_offset = offsetof(struct misc_cg, events_file), .seq_show = misc_events_show, }, + { + .name = "events.local", + .flags = CFTYPE_NOT_ON_ROOT, + .file_offset = offsetof(struct misc_cg, events_local_file), + .seq_show = misc_events_local_show, + }, {} }; -- 2.25.1