From: Tejun Heo <tj@kernel.org>
To: torvalds@linux-foundation.org, mingo@redhat.com,
peterz@infradead.org, juri.lelli@redhat.com,
vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
bristot@redhat.com, vschneid@redhat.com, ast@kernel.org,
daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org,
joshdon@google.com, brho@google.com, pjt@google.com,
derkling@google.com, haoluo@google.com, dvernet@meta.com,
dschatzberg@meta.com, dskarlat@cs.cmu.edu, riel@surriel.com,
changwoo@igalia.com, himadrics@inria.fr, memxor@gmail.com
Cc: linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
kernel-team@meta.com, Tejun Heo <tj@kernel.org>
Subject: [PATCH 01/36] cgroup: Implement cgroup_show_cftypes()
Date: Fri, 10 Nov 2023 16:47:27 -1000 [thread overview]
Message-ID: <20231111024835.2164816-2-tj@kernel.org> (raw)
In-Reply-To: <20231111024835.2164816-1-tj@kernel.org>
Implement cgroup_show_cftypes() which shows and hides all cgroup files
associated with the specified set of cgroup file types. CFTYPE_HIDDEN flag
is added so that files can be created hidden from the get-go.
cgroup_show_cftypes() can be used whether the cftypes are added or not. It
also combines with cgroup_show_file() so that a given file is visible iff
both its cftype and cfile are visible.
This will be used by a new sched_class to selectively show and hide CPU
controller interface files depending on whether they're supported.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Vernet <dvernet@meta.com>
Acked-by: Josh Don <joshdon@google.com>
Acked-by: Hao Luo <haoluo@google.com>
Acked-by: Barret Rhoden <brho@google.com>
---
include/linux/cgroup-defs.h | 8 +++
include/linux/cgroup.h | 1 +
kernel/cgroup/cgroup.c | 97 ++++++++++++++++++++++++++++++++++---
3 files changed, 99 insertions(+), 7 deletions(-)
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 265da00a1a8b..6194d7c13573 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -127,12 +127,18 @@ enum {
CFTYPE_WORLD_WRITABLE = (1 << 4), /* (DON'T USE FOR NEW FILES) S_IWUGO */
CFTYPE_DEBUG = (1 << 5), /* create when cgroup_debug */
+ CFTYPE_HIDDEN = (1 << 6), /* file type hidden, see cgroup_show_cftypes() */
+
/* internal flags, do not use outside cgroup core proper */
__CFTYPE_ONLY_ON_DFL = (1 << 16), /* only on default hierarchy */
__CFTYPE_NOT_ON_DFL = (1 << 17), /* not on default hierarchy */
__CFTYPE_ADDED = (1 << 18),
};
+enum cfile_flags {
+ CFILE_HIDDEN = (1 << 0), /* file instance hidden */
+};
+
/*
* cgroup_file is the handle for a file instance created in a cgroup which
* is used, for example, to generate file changed notifications. This can
@@ -140,7 +146,9 @@ enum {
*/
struct cgroup_file {
/* do not access any fields from outside cgroup core */
+ struct cftype *cft;
struct kernfs_node *kn;
+ unsigned int flags;
unsigned long notified_at;
struct timer_list notify_timer;
};
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 0ef0af66080e..d164eaeacfa6 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -113,6 +113,7 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from);
int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_rm_cftypes(struct cftype *cfts);
+void cgroup_show_cftype(struct cftype *cft, bool show);
void cgroup_file_notify(struct cgroup_file *cfile);
void cgroup_file_show(struct cgroup_file *cfile, bool show);
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 484adb375b15..d00fa84edd4c 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4210,10 +4210,13 @@ static int cgroup_add_file(struct cgroup_subsys_state *css, struct cgroup *cgrp,
return ret;
}
+ kernfs_show(kn, !(cft->flags & CFTYPE_HIDDEN));
+
if (cft->file_offset) {
struct cgroup_file *cfile = (void *)css + cft->file_offset;
timer_setup(&cfile->notify_timer, cgroup_file_notify_timer, 0);
+ cfile->cft = cft;
spin_lock_irq(&cgroup_file_kn_lock);
cfile->kn = kn;
@@ -4489,6 +4492,24 @@ void cgroup_file_notify(struct cgroup_file *cfile)
spin_unlock_irqrestore(&cgroup_file_kn_lock, flags);
}
+static struct kernfs_node *cfile_kn_get(struct cgroup_file *cfile)
+{
+ struct kernfs_node *kn;
+
+ spin_lock_irq(&cgroup_file_kn_lock);
+ kn = cfile->kn;
+ kernfs_get(kn);
+ spin_unlock_irq(&cgroup_file_kn_lock);
+
+ return kn;
+}
+
+static bool cfile_visible(struct cgroup_file *cfile)
+{
+ return !(cfile->cft->flags & CFTYPE_HIDDEN) &&
+ !(cfile->flags & CFILE_HIDDEN);
+}
+
/**
* cgroup_file_show - show or hide a hidden cgroup file
* @cfile: target cgroup_file obtained by setting cftype->file_offset
@@ -4498,15 +4519,20 @@ void cgroup_file_show(struct cgroup_file *cfile, bool show)
{
struct kernfs_node *kn;
- spin_lock_irq(&cgroup_file_kn_lock);
- kn = cfile->kn;
- kernfs_get(kn);
- spin_unlock_irq(&cgroup_file_kn_lock);
+ mutex_lock(&cgroup_mutex);
- if (kn)
- kernfs_show(kn, show);
+ if (show)
+ cfile->flags &= ~CFILE_HIDDEN;
+ else
+ cfile->flags |= CFILE_HIDDEN;
- kernfs_put(kn);
+ kn = cfile_kn_get(cfile);
+ if (kn) {
+ kernfs_show(kn, cfile_visible(cfile));
+ kernfs_put(kn);
+ }
+
+ mutex_unlock(&cgroup_mutex);
}
/**
@@ -5534,6 +5560,63 @@ static void offline_css(struct cgroup_subsys_state *css)
wake_up_all(&css->cgroup->offline_waitq);
}
+/**
+ * cgroup_show_cftype - show or hide a cgroup file type
+ * @cft: cftype to show or hide
+ * @show: whether to show or hide
+ *
+ * Sets %CFTYPE_HIDDEN and shows/hides the matching files according to @show.
+ * @cft may or may not be added at the time of this call. After hiding, it's
+ * guaranteed that there are no in-flight operations on the hidden files.
+ */
+void cgroup_show_cftype(struct cftype *cft, bool show)
+{
+ struct cgroup_subsys *ss = cft->ss;
+ struct cgroup *root = ss ? &ss->root->cgrp : &cgrp_dfl_root.cgrp;
+ struct cgroup_subsys_state *css;
+
+ mutex_lock(&cgroup_mutex);
+
+ if (show)
+ cft->flags &= ~CFTYPE_HIDDEN;
+ else
+ cft->flags |= CFTYPE_HIDDEN;
+
+ if (!(cft->flags & __CFTYPE_ADDED))
+ goto out_unlock;
+
+ css_for_each_descendant_pre(css, cgroup_css(root, ss)) {
+ struct cgroup *cgrp = css->cgroup;
+ struct kernfs_node *kn;
+
+ if (!(css->flags & CSS_VISIBLE))
+ continue;
+
+ if (cft->file_offset) {
+ struct cgroup_file *cfile =
+ (void *)css + cft->file_offset;
+
+ kn = cfile_kn_get(cfile);
+ if (kn) {
+ kernfs_show(kn, cfile_visible(cfile));
+ kernfs_put(kn);
+ }
+ } else {
+ char buf[CGROUP_FILE_NAME_MAX];
+
+ kn = kernfs_find_and_get(cgrp->kn,
+ cgroup_file_name(cgrp, cft, buf));
+ if (kn) {
+ kernfs_show(kn, show);
+ kernfs_put(kn);
+ }
+ }
+ }
+
+out_unlock:
+ mutex_unlock(&cgroup_mutex);
+}
+
/**
* css_create - create a cgroup_subsys_state
* @cgrp: the cgroup new css will be associated with
--
2.42.0
next prev parent reply other threads:[~2023-11-11 2:49 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-11 2:47 [PATCHSET v5] sched: Implement BPF extensible scheduler class Tejun Heo
2023-11-11 2:47 ` Tejun Heo [this message]
2023-11-11 2:47 ` [PATCH 02/36] sched: Restructure sched_class order sanity checks in sched_init() Tejun Heo
2023-11-11 2:47 ` [PATCH 03/36] sched: Allow sched_cgroup_fork() to fail and introduce sched_cancel_fork() Tejun Heo
2023-11-11 2:47 ` [PATCH 04/36] sched: Add sched_class->reweight_task() Tejun Heo
2023-11-11 2:47 ` [PATCH 05/36] sched: Add sched_class->switching_to() and expose check_class_changing/changed() Tejun Heo
2023-11-11 2:47 ` [PATCH 06/36] sched: Factor out cgroup weight conversion functions Tejun Heo
2023-11-11 2:47 ` [PATCH 07/36] sched: Expose css_tg() and __setscheduler_prio() Tejun Heo
2023-11-11 2:47 ` [PATCH 08/36] sched: Enumerate CPU cgroup file types Tejun Heo
2023-11-11 2:47 ` [PATCH 09/36] sched: Add @reason to sched_class->rq_{on|off}line() Tejun Heo
2023-11-11 2:47 ` [PATCH 10/36] sched: Add normal_policy() Tejun Heo
2023-11-11 2:47 ` [PATCH 11/36] sched_ext: Add boilerplate for extensible scheduler class Tejun Heo
2023-11-11 2:47 ` [PATCH 12/36] sched_ext: Implement BPF " Tejun Heo
2023-11-13 13:34 ` Changwoo Min
2023-11-14 19:07 ` Tejun Heo
2023-11-13 20:04 ` Andrea Righi
2023-11-14 19:07 ` Tejun Heo
2023-11-23 8:07 ` Andrea Righi
2023-11-25 19:59 ` Tejun Heo
2023-11-26 9:05 ` Andrea Righi
2023-12-07 2:04 ` [PATCH] scx: set p->scx.ops_state using atomic_long_set_release Changwoo Min
2023-12-08 0:16 ` Tejun Heo
2024-03-23 2:37 ` [PATCH 12/36] sched_ext: Implement BPF extensible scheduler class Joel Fernandes
2024-03-23 22:12 ` Tejun Heo
2024-04-25 21:28 ` Joel Fernandes
2024-04-26 16:57 ` Barret Rhoden
2024-04-26 21:58 ` Tejun Heo
2023-11-11 2:47 ` [PATCH 13/36] sched_ext: Add scx_simple and scx_example_qmap example schedulers Tejun Heo
2023-11-12 4:17 ` kernel test robot
2023-11-12 18:06 ` Tejun Heo
2023-11-11 2:47 ` [PATCH 14/36] sched_ext: Add sysrq-S which disables the BPF scheduler Tejun Heo
2023-11-11 2:47 ` [PATCH 15/36] sched_ext: Implement runnable task stall watchdog Tejun Heo
2023-11-11 2:47 ` [PATCH 16/36] sched_ext: Allow BPF schedulers to disallow specific tasks from joining SCHED_EXT Tejun Heo
2023-11-11 2:47 ` [PATCH 17/36] sched_ext: Allow BPF schedulers to switch all eligible tasks into sched_ext Tejun Heo
2023-11-11 2:47 ` [PATCH 18/36] sched_ext: Print sched_ext info when dumping stack Tejun Heo
2023-11-14 19:23 ` [PATCH v2 " Tejun Heo
2023-11-11 2:47 ` [PATCH 19/36] sched_ext: Implement scx_bpf_kick_cpu() and task preemption support Tejun Heo
2023-11-11 2:47 ` [PATCH 20/36] sched_ext: Add a central scheduler which makes all scheduling decisions on one CPU Tejun Heo
2023-11-11 2:47 ` [PATCH 21/36] sched_ext: Make watchdog handle ops.dispatch() looping stall Tejun Heo
2023-11-11 2:47 ` [PATCH 22/36] sched_ext: Add task state tracking operations Tejun Heo
2023-11-11 2:47 ` [PATCH 23/36] sched_ext: Implement tickless support Tejun Heo
2023-11-11 2:47 ` [PATCH 24/36] sched_ext: Track tasks that are subjects of the in-flight SCX operation Tejun Heo
2023-11-11 2:47 ` [PATCH 25/36] sched_ext: Add cgroup support Tejun Heo
2023-11-11 2:47 ` [PATCH 26/36] sched_ext: Add a cgroup-based core-scheduling scheduler Tejun Heo
2023-11-11 2:47 ` [PATCH 27/36] sched_ext: Add a cgroup scheduler which uses flattened hierarchy Tejun Heo
2023-11-11 2:47 ` [PATCH 28/36] sched_ext: Implement SCX_KICK_WAIT Tejun Heo
2023-11-11 2:47 ` [PATCH 29/36] sched_ext: Implement sched_ext_ops.cpu_acquire/release() Tejun Heo
2023-11-11 2:47 ` [PATCH 30/36] sched_ext: Implement sched_ext_ops.cpu_online/offline() Tejun Heo
2023-11-11 2:47 ` [PATCH 31/36] sched_ext: Implement core-sched support Tejun Heo
2023-11-11 2:47 ` [PATCH 32/36] sched_ext: Add vtime-ordered priority queue to dispatch_q's Tejun Heo
2023-11-11 2:47 ` [PATCH 33/36] sched_ext: Documentation: scheduler: Document extensible scheduler class Tejun Heo
2023-11-11 2:48 ` [PATCH 34/36] sched_ext: Add a basic, userland vruntime scheduler Tejun Heo
2023-11-11 2:48 ` [PATCH 35/36] sched_ext: Add scx_rusty, a rust userspace hybrid scheduler Tejun Heo
2023-11-11 2:48 ` [PATCH 36/36] sched_ext: Add scx_layered, a highly configurable multi-layer scheduler Tejun Heo
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