aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/RCU/stallwarn.rst4
-rw-r--r--arch/arm/mach-imx/cpuidle-imx6q.c5
-rw-r--r--drivers/acpi/processor_idle.c5
-rw-r--r--drivers/cpuidle/cpuidle.c9
-rw-r--r--include/linux/context_tracking.h8
-rw-r--r--include/linux/rcupdate.h2
-rw-r--r--kernel/context_tracking.c15
-rw-r--r--kernel/locking/lockdep.c2
-rw-r--r--kernel/rcu/Kconfig2
-rw-r--r--kernel/rcu/tree.c2
-rw-r--r--kernel/rcu/update.c2
-rw-r--r--kernel/sched/idle.c10
-rw-r--r--kernel/sched/sched.h1
-rw-r--r--kernel/time/Kconfig6
14 files changed, 53 insertions, 20 deletions
diff --git a/Documentation/RCU/stallwarn.rst b/Documentation/RCU/stallwarn.rst
index 794837eb519b..b95bda7755fa 100644
--- a/Documentation/RCU/stallwarn.rst
+++ b/Documentation/RCU/stallwarn.rst
@@ -97,8 +97,8 @@ warnings:
which will include additional debugging information.
- A low-level kernel issue that either fails to invoke one of the
- variants of rcu_user_enter(), rcu_user_exit(), rcu_idle_enter(),
- rcu_idle_exit(), rcu_irq_enter(), or rcu_irq_exit() on the one
+ variants of rcu_user_enter(), rcu_user_exit(), ct_idle_enter(),
+ ct_idle_exit(), rcu_irq_enter(), or rcu_irq_exit() on the one
hand, or that invokes one of them too many times on the other.
Historically, the most frequent issue has been an omission
of either irq_enter() or irq_exit(), which in turn invoke
diff --git a/arch/arm/mach-imx/cpuidle-imx6q.c b/arch/arm/mach-imx/cpuidle-imx6q.c
index 094337dc1bc7..d086cbae09c3 100644
--- a/arch/arm/mach-imx/cpuidle-imx6q.c
+++ b/arch/arm/mach-imx/cpuidle-imx6q.c
@@ -3,6 +3,7 @@
* Copyright (C) 2012 Freescale Semiconductor, Inc.
*/
+#include <linux/context_tracking.h>
#include <linux/cpuidle.h>
#include <linux/module.h>
#include <asm/cpuidle.h>
@@ -24,9 +25,9 @@ static int imx6q_enter_wait(struct cpuidle_device *dev,
imx6_set_lpm(WAIT_UNCLOCKED);
raw_spin_unlock(&cpuidle_lock);
- rcu_idle_enter();
+ ct_idle_enter();
cpu_do_idle();
- rcu_idle_exit();
+ ct_idle_exit();
raw_spin_lock(&cpuidle_lock);
if (num_idle_cpus-- == num_online_cpus())
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 6a5572a1a80c..1401d193a2df 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -23,6 +23,7 @@
#include <linux/minmax.h>
#include <linux/perf_event.h>
#include <acpi/processor.h>
+#include <linux/context_tracking.h>
/*
* Include the apic definitions for x86 to have the APIC timer related defines
@@ -647,11 +648,11 @@ static int acpi_idle_enter_bm(struct cpuidle_driver *drv,
raw_spin_unlock(&c3_lock);
}
- rcu_idle_enter();
+ ct_idle_enter();
acpi_idle_do_entry(cx);
- rcu_idle_exit();
+ ct_idle_exit();
/* Re-enable bus master arbitration */
if (dis_bm) {
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index ef2ea1b12cd8..62dd956025f3 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -23,6 +23,7 @@
#include <linux/suspend.h>
#include <linux/tick.h>
#include <linux/mmu_context.h>
+#include <linux/context_tracking.h>
#include <trace/events/power.h>
#include "cpuidle.h"
@@ -150,12 +151,12 @@ static void enter_s2idle_proper(struct cpuidle_driver *drv,
*/
stop_critical_timings();
if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
- rcu_idle_enter();
+ ct_idle_enter();
target_state->enter_s2idle(dev, drv, index);
if (WARN_ON_ONCE(!irqs_disabled()))
local_irq_disable();
if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
- rcu_idle_exit();
+ ct_idle_exit();
tick_unfreeze();
start_critical_timings();
@@ -233,10 +234,10 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
stop_critical_timings();
if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
- rcu_idle_enter();
+ ct_idle_enter();
entered_state = target_state->enter(dev, drv, index);
if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
- rcu_idle_exit();
+ ct_idle_exit();
start_critical_timings();
sched_clock_idle_wakeup_event();
diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h
index e35ae66b4794..01abadb2f993 100644
--- a/include/linux/context_tracking.h
+++ b/include/linux/context_tracking.h
@@ -119,4 +119,12 @@ extern void context_tracking_init(void);
static inline void context_tracking_init(void) { }
#endif /* CONFIG_CONTEXT_TRACKING_USER_FORCE */
+#ifdef CONFIG_CONTEXT_TRACKING_IDLE
+extern void ct_idle_enter(void);
+extern void ct_idle_exit(void);
+#else
+static inline void ct_idle_enter(void) { }
+static inline void ct_idle_exit(void) { }
+#endif /* !CONFIG_CONTEXT_TRACKING_IDLE */
+
#endif
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 1a32036c918c..6ebe754501c3 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -128,7 +128,7 @@ static inline void rcu_nocb_flush_deferred_wakeup(void) { }
* @a: Code that RCU needs to pay attention to.
*
* RCU read-side critical sections are forbidden in the inner idle loop,
- * that is, between the rcu_idle_enter() and the rcu_idle_exit() -- RCU
+ * that is, between the ct_idle_enter() and the ct_idle_exit() -- RCU
* will happily ignore any such read-side critical sections. However,
* things like powertop need tracepoints in the inner idle loop.
*
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index f3dec1be2bf6..c0b3798d4e94 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -22,6 +22,21 @@
#include <linux/export.h>
#include <linux/kprobes.h>
+
+#ifdef CONFIG_CONTEXT_TRACKING_IDLE
+noinstr void ct_idle_enter(void)
+{
+ rcu_idle_enter();
+}
+EXPORT_SYMBOL_GPL(ct_idle_enter);
+
+void ct_idle_exit(void)
+{
+ rcu_idle_exit();
+}
+EXPORT_SYMBOL_GPL(ct_idle_exit);
+#endif /* #ifdef CONFIG_CONTEXT_TRACKING_IDLE */
+
#ifdef CONFIG_CONTEXT_TRACKING_USER
#define CREATE_TRACE_POINTS
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index f06b91ca6482..5ea690cb4f7a 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -6570,7 +6570,7 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
/*
* If a CPU is in the RCU-free window in idle (ie: in the section
- * between rcu_idle_enter() and rcu_idle_exit(), then RCU
+ * between ct_idle_enter() and ct_idle_exit(), then RCU
* considers that CPU to be in an "extended quiescent state",
* which means that RCU will be completely ignoring that CPU.
* Therefore, rcu_read_lock() and friends have absolutely no
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index 1c630e573548..3fa24e63d6f9 100644
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -8,6 +8,8 @@ menu "RCU Subsystem"
config TREE_RCU
bool
default y if SMP
+ # Dynticks-idle tracking
+ select CONTEXT_TRACKING_IDLE
help
This option selects the RCU implementation that is
designed for very large SMP system with hundreds or
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 9a5edab5558c..051fed0844b6 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -664,7 +664,6 @@ void noinstr rcu_idle_enter(void)
WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
rcu_eqs_enter(false);
}
-EXPORT_SYMBOL_GPL(rcu_idle_enter);
#ifdef CONFIG_NO_HZ_FULL
@@ -904,7 +903,6 @@ void noinstr rcu_idle_exit(void)
rcu_eqs_exit(false);
raw_local_irq_restore(flags);
}
-EXPORT_SYMBOL_GPL(rcu_idle_exit);
#ifdef CONFIG_NO_HZ_FULL
/**
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index fc7fef575606..147214b2cd68 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -85,7 +85,7 @@ module_param(rcu_normal_after_boot, int, 0444);
* and while lockdep is disabled.
*
* Note that if the CPU is in the idle loop from an RCU point of view (ie:
- * that we are in the section between rcu_idle_enter() and rcu_idle_exit())
+ * that we are in the section between ct_idle_enter() and ct_idle_exit())
* then rcu_read_lock_held() sets ``*ret`` to false even if the CPU did an
* rcu_read_lock(). The reason for this is that RCU ignores CPUs that are
* in such a section, considering these as in extended quiescent state,
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 328cccbee444..f26ab2675f7d 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -53,14 +53,14 @@ static noinline int __cpuidle cpu_idle_poll(void)
{
trace_cpu_idle(0, smp_processor_id());
stop_critical_timings();
- rcu_idle_enter();
+ ct_idle_enter();
local_irq_enable();
while (!tif_need_resched() &&
(cpu_idle_force_poll || tick_check_broadcast_expired()))
cpu_relax();
- rcu_idle_exit();
+ ct_idle_exit();
start_critical_timings();
trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
@@ -98,12 +98,12 @@ void __cpuidle default_idle_call(void)
*
* Trace IRQs enable here, then switch off RCU, and have
* arch_cpu_idle() use raw_local_irq_enable(). Note that
- * rcu_idle_enter() relies on lockdep IRQ state, so switch that
+ * ct_idle_enter() relies on lockdep IRQ state, so switch that
* last -- this is very similar to the entry code.
*/
trace_hardirqs_on_prepare();
lockdep_hardirqs_on_prepare();
- rcu_idle_enter();
+ ct_idle_enter();
lockdep_hardirqs_on(_THIS_IP_);
arch_cpu_idle();
@@ -116,7 +116,7 @@ void __cpuidle default_idle_call(void)
*/
raw_local_irq_disable();
lockdep_hardirqs_off(_THIS_IP_);
- rcu_idle_exit();
+ ct_idle_exit();
lockdep_hardirqs_on(_THIS_IP_);
raw_local_irq_enable();
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 47b89a0fc6e5..0cfe2d0af294 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -27,6 +27,7 @@
#include <linux/capability.h>
#include <linux/cgroup_api.h>
#include <linux/cgroup.h>
+#include <linux/context_tracking.h>
#include <linux/cpufreq.h>
#include <linux/cpumask_api.h>
#include <linux/ctype.h>
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 41f99bcfe9e6..a41753be1a2b 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -76,6 +76,12 @@ config TIME_KUNIT_TEST
config CONTEXT_TRACKING
bool
+config CONTEXT_TRACKING_IDLE
+ bool
+ select CONTEXT_TRACKING
+ help
+ Tracks idle state on behalf of RCU.
+
if GENERIC_CLOCKEVENTS
menu "Timers subsystem"
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.