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 14/36] sched_ext: Add sysrq-S which disables the BPF scheduler
Date: Fri, 10 Nov 2023 16:47:40 -1000 [thread overview]
Message-ID: <20231111024835.2164816-15-tj@kernel.org> (raw)
In-Reply-To: <20231111024835.2164816-1-tj@kernel.org>
This enables the admin to abort the BPF scheduler and revert to CFS anytime.
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>
---
drivers/tty/sysrq.c | 1 +
include/linux/sched/ext.h | 1 +
kernel/sched/build_policy.c | 1 +
kernel/sched/ext.c | 20 ++++++++++++++++++++
4 files changed, 23 insertions(+)
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 23198e3f1461..eebdf76b05b4 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -519,6 +519,7 @@ static const struct sysrq_key_op *sysrq_key_table[62] = {
NULL, /* P */
NULL, /* Q */
NULL, /* R */
+ /* S: May be registered by sched_ext for resetting */
NULL, /* S */
NULL, /* T */
NULL, /* U */
diff --git a/include/linux/sched/ext.h b/include/linux/sched/ext.h
index b6462d953ec6..cad8ab4d782a 100644
--- a/include/linux/sched/ext.h
+++ b/include/linux/sched/ext.h
@@ -55,6 +55,7 @@ enum scx_exit_kind {
SCX_EXIT_DONE,
SCX_EXIT_UNREG = 64, /* BPF unregistration */
+ SCX_EXIT_SYSRQ, /* requested by 'S' sysrq */
SCX_EXIT_ERROR = 1024, /* runtime error, error msg contains details */
SCX_EXIT_ERROR_BPF, /* ERROR but triggered through scx_bpf_error() */
diff --git a/kernel/sched/build_policy.c b/kernel/sched/build_policy.c
index 4c658b21f603..005025f55bea 100644
--- a/kernel/sched/build_policy.c
+++ b/kernel/sched/build_policy.c
@@ -28,6 +28,7 @@
#include <linux/suspend.h>
#include <linux/tsacct_kern.h>
#include <linux/vtime.h>
+#include <linux/sysrq.h>
#include <linux/percpu-rwsem.h>
#include <uapi/linux/sched/types.h>
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 7b78f77d2293..2d9996a96d3a 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -1981,6 +1981,9 @@ static void scx_ops_disable_workfn(struct kthread_work *work)
case SCX_EXIT_UNREG:
reason = "BPF scheduler unregistered";
break;
+ case SCX_EXIT_SYSRQ:
+ reason = "disabled by sysrq-S";
+ break;
case SCX_EXIT_ERROR:
reason = "runtime error";
break;
@@ -2599,6 +2602,21 @@ struct bpf_struct_ops bpf_sched_ext_ops = {
.name = "sched_ext_ops",
};
+static void sysrq_handle_sched_ext_reset(u8 key)
+{
+ if (scx_ops_helper)
+ scx_ops_disable(SCX_EXIT_SYSRQ);
+ else
+ pr_info("sched_ext: BPF scheduler not yet used\n");
+}
+
+static const struct sysrq_key_op sysrq_sched_ext_reset_op = {
+ .handler = sysrq_handle_sched_ext_reset,
+ .help_msg = "reset-sched-ext(S)",
+ .action_msg = "Disable sched_ext and revert all tasks to CFS",
+ .enable_mask = SYSRQ_ENABLE_RTNICE,
+};
+
void __init init_sched_ext_class(void)
{
int cpu;
@@ -2622,6 +2640,8 @@ void __init init_sched_ext_class(void)
init_dsq(&rq->scx.local_dsq, SCX_DSQ_LOCAL);
}
+
+ register_sysrq_key('S', &sysrq_sched_ext_reset_op);
}
--
2.42.0
next prev parent reply other threads:[~2023-11-11 2:50 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 ` [PATCH 01/36] cgroup: Implement cgroup_show_cftypes() Tejun Heo
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 ` Tejun Heo [this message]
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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231111024835.2164816-15-tj@kernel.org \
--to=tj@kernel.org \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=brho@google.com \
--cc=bristot@redhat.com \
--cc=bsegall@google.com \
--cc=changwoo@igalia.com \
--cc=daniel@iogearbox.net \
--cc=derkling@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=dschatzberg@meta.com \
--cc=dskarlat@cs.cmu.edu \
--cc=dvernet@meta.com \
--cc=haoluo@google.com \
--cc=himadrics@inria.fr \
--cc=joshdon@google.com \
--cc=juri.lelli@redhat.com \
--cc=kernel-team@meta.com \
--cc=linux-kernel@vger.kernel.org \
--cc=martin.lau@kernel.org \
--cc=memxor@gmail.com \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=riel@surriel.com \
--cc=rostedt@goodmis.org \
--cc=torvalds@linux-foundation.org \
--cc=vincent.guittot@linaro.org \
--cc=vschneid@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).