From: "tip-bot2 for Peter Zijlstra (Intel)" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>,
Frederic Weisbecker <frederic@kernel.org>,
Ingo Molnar <mingo@kernel.org>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [tip: sched/core] preempt/dynamic: Provide cond_resched() and might_resched() static calls
Date: Wed, 17 Feb 2021 13:17:34 -0000 [thread overview]
Message-ID: <161356785481.20312.6418097474032725065.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20210118141223.123667-6-frederic@kernel.org>
The following commit has been merged into the sched/core branch of tip:
Commit-ID: b965f1ddb47daa5b8b2e2bc9c921431236830367
Gitweb: https://git.kernel.org/tip/b965f1ddb47daa5b8b2e2bc9c921431236830367
Author: Peter Zijlstra (Intel) <peterz@infradead.org>
AuthorDate: Mon, 18 Jan 2021 15:12:20 +01:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 17 Feb 2021 14:12:42 +01:00
preempt/dynamic: Provide cond_resched() and might_resched() static calls
Provide static calls to control cond_resched() (called in !CONFIG_PREEMPT)
and might_resched() (called in CONFIG_PREEMPT_VOLUNTARY) to that we
can override their behaviour when preempt= is overriden.
Since the default behaviour is full preemption, both their calls are
ignored when preempt= isn't passed.
[fweisbec: branch might_resched() directly to __cond_resched(), only
define static calls when PREEMPT_DYNAMIC]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-6-frederic@kernel.org
---
include/linux/kernel.h | 23 +++++++++++++++++++----
include/linux/sched.h | 27 ++++++++++++++++++++++++---
kernel/sched/core.c | 16 +++++++++++++---
3 files changed, 56 insertions(+), 10 deletions(-)
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index f7902d8..cfd3d34 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -15,7 +15,7 @@
#include <linux/typecheck.h>
#include <linux/printk.h>
#include <linux/build_bug.h>
-
+#include <linux/static_call_types.h>
#include <asm/byteorder.h>
#include <uapi/linux/kernel.h>
@@ -81,11 +81,26 @@ struct pt_regs;
struct user;
#ifdef CONFIG_PREEMPT_VOLUNTARY
-extern int _cond_resched(void);
-# define might_resched() _cond_resched()
+
+extern int __cond_resched(void);
+# define might_resched() __cond_resched()
+
+#elif defined(CONFIG_PREEMPT_DYNAMIC)
+
+extern int __cond_resched(void);
+
+DECLARE_STATIC_CALL(might_resched, __cond_resched);
+
+static __always_inline void might_resched(void)
+{
+ static_call(might_resched)();
+}
+
#else
+
# define might_resched() do { } while (0)
-#endif
+
+#endif /* CONFIG_PREEMPT_* */
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
extern void ___might_sleep(const char *file, int line, int preempt_offset);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e115222..2f35594 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1871,11 +1871,32 @@ static inline int test_tsk_need_resched(struct task_struct *tsk)
* value indicates whether a reschedule was done in fact.
* cond_resched_lock() will drop the spinlock before scheduling,
*/
-#ifndef CONFIG_PREEMPTION
-extern int _cond_resched(void);
+#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
+extern int __cond_resched(void);
+
+#ifdef CONFIG_PREEMPT_DYNAMIC
+
+DECLARE_STATIC_CALL(cond_resched, __cond_resched);
+
+static __always_inline int _cond_resched(void)
+{
+ return static_call(cond_resched)();
+}
+
#else
+
+static inline int _cond_resched(void)
+{
+ return __cond_resched();
+}
+
+#endif /* CONFIG_PREEMPT_DYNAMIC */
+
+#else
+
static inline int _cond_resched(void) { return 0; }
-#endif
+
+#endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */
#define cond_resched() ({ \
___might_sleep(__FILE__, __LINE__, 0); \
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4afbdd2..f7c8fd8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6785,17 +6785,27 @@ SYSCALL_DEFINE0(sched_yield)
return 0;
}
-#ifndef CONFIG_PREEMPTION
-int __sched _cond_resched(void)
+#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
+int __sched __cond_resched(void)
{
if (should_resched(0)) {
preempt_schedule_common();
return 1;
}
+#ifndef CONFIG_PREEMPT_RCU
rcu_all_qs();
+#endif
return 0;
}
-EXPORT_SYMBOL(_cond_resched);
+EXPORT_SYMBOL(__cond_resched);
+#endif
+
+#ifdef CONFIG_PREEMPT_DYNAMIC
+DEFINE_STATIC_CALL_RET0(cond_resched, __cond_resched);
+EXPORT_STATIC_CALL(cond_resched);
+
+DEFINE_STATIC_CALL_RET0(might_resched, __cond_resched);
+EXPORT_STATIC_CALL(might_resched);
#endif
/*
next prev parent reply other threads:[~2021-02-17 13:28 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-18 14:12 [RFC PATCH 0/7] preempt: Tune preemption flavour on boot v4 Frederic Weisbecker
2021-01-18 14:12 ` [RFC PATCH 1/8] static_call/x86: Add __static_call_return0() Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Peter Zijlstra
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra
2021-01-18 14:12 ` [RFC PATCH 2/8] static_call: Provide DEFINE_STATIC_CALL_RET0() Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Frederic Weisbecker
2021-02-17 13:17 ` tip-bot2 for Frederic Weisbecker
2021-01-18 14:12 ` [RFC PATCH 3/8] static_call: Pull some static_call declarations to the type headers Frederic Weisbecker
2021-01-19 10:46 ` Jürgen Groß
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Peter Zijlstra
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra
2021-01-18 14:12 ` [RFC PATCH 4/8] preempt: Introduce CONFIG_PREEMPT_DYNAMIC Frederic Weisbecker
2021-01-22 16:53 ` Peter Zijlstra
2021-01-28 12:17 ` Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Michal Hocko
2021-02-17 13:17 ` tip-bot2 for Michal Hocko
2021-01-18 14:12 ` [RFC PATCH 5/8] preempt/dynamic: Provide cond_resched() and might_resched() static calls Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Peter Zijlstra (Intel)
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra (Intel) [this message]
2021-01-18 14:12 ` [RFC PATCH 6/8] preempt/dynamic: Provide preempt_schedule[_notrace]() " Frederic Weisbecker
2021-01-21 21:58 ` Peter Zijlstra
2021-01-21 22:25 ` Peter Zijlstra
2021-01-22 16:52 ` Peter Zijlstra
2021-01-22 16:57 ` Ard Biesheuvel
2021-01-22 17:08 ` Peter Zijlstra
2021-02-08 12:00 ` [tip: sched/core] sched: Add /debug/sched_preempt tip-bot2 for Peter Zijlstra
2021-02-09 15:45 ` tip-bot2 for Peter Zijlstra
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra
2021-01-25 23:40 ` [RFC PATCH 6/8] preempt/dynamic: Provide preempt_schedule[_notrace]() static calls Josh Poimboeuf
2021-01-26 9:24 ` Peter Zijlstra
2021-01-26 23:57 ` Josh Poimboeuf
2021-01-27 9:13 ` Peter Zijlstra
2021-01-27 11:27 ` Peter Zijlstra
2021-01-27 15:59 ` Josh Poimboeuf
2021-01-27 16:19 ` Peter Zijlstra
2021-01-27 16:33 ` Josh Poimboeuf
2021-01-27 18:44 ` Peter Zijlstra
2021-01-27 19:00 ` Josh Poimboeuf
2021-01-27 19:02 ` Josh Poimboeuf
2021-01-27 23:18 ` Josh Poimboeuf
2021-02-03 14:04 ` Peter Zijlstra
2021-02-05 15:30 ` Peter Zijlstra
2021-02-06 2:31 ` Josh Poimboeuf
2021-02-06 9:03 ` Peter Zijlstra
2021-02-05 15:22 ` Peter Zijlstra
2021-02-08 12:00 ` [tip: sched/core] static_call: Allow module use without exposing static_call_key tip-bot2 for Josh Poimboeuf
2021-02-09 15:45 ` tip-bot2 for Josh Poimboeuf
2021-02-17 13:17 ` tip-bot2 for Josh Poimboeuf
2021-02-08 12:00 ` [tip: sched/core] preempt/dynamic: Provide preempt_schedule[_notrace]() static calls tip-bot2 for Peter Zijlstra (Intel)
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra (Intel)
2021-01-18 14:12 ` [RFC PATCH 7/8] preempt/dynamic: Provide irqentry_exit_cond_resched() static call Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Peter Zijlstra (Intel)
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra (Intel)
2021-01-18 14:12 ` [RFC PATCH 8/8] preempt/dynamic: Support dynamic preempt with preempt= boot option Frederic Weisbecker
2021-02-08 12:00 ` [tip: sched/core] " tip-bot2 for Peter Zijlstra (Intel)
2021-02-09 15:45 ` tip-bot2 for Peter Zijlstra (Intel)
2021-02-17 13:17 ` tip-bot2 for Peter Zijlstra (Intel)
2021-01-21 21:22 ` [RFC PATCH 0/7] preempt: Tune preemption flavour on boot v4 Peter Zijlstra
2021-01-22 15:02 ` Paul E. McKenney
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=161356785481.20312.6418097474032725065.tip-bot2@tip-bot2 \
--to=tip-bot2@linutronix.de \
--cc=frederic@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=x86@kernel.org \
/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 NNTP newsgroup(s).