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-rw-r--r--kernel/cred.c2
-rw-r--r--kernel/events/core.c8
-rw-r--r--kernel/jump_label.c18
-rw-r--r--kernel/pm_qos_params.c33
-rw-r--r--kernel/power/hibernate.c220
-rw-r--r--kernel/rcutree.c164
-rw-r--r--kernel/rcutree.h30
-rw-r--r--kernel/rcutree_plugin.h24
-rw-r--r--kernel/rcutree_trace.c12
-rw-r--r--kernel/trace/ftrace.c31
-rw-r--r--kernel/trace/ring_buffer.c10
-rw-r--r--kernel/trace/trace.h15
-rw-r--r--kernel/trace/trace_events.c7
-rw-r--r--kernel/trace/trace_output.c27
-rw-r--r--kernel/watchdog.c9
15 files changed, 330 insertions, 280 deletions
diff --git a/kernel/cred.c b/kernel/cred.c
index e12c8af7..174fa84 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -1,4 +1,4 @@
-/* Task credentials management - see Documentation/credentials.txt
+/* Task credentials management - see Documentation/security/credentials.txt
*
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index c09767f..d863b3c 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5028,6 +5028,14 @@ static int __perf_event_overflow(struct perf_event *event, int nmi,
else
perf_event_output(event, nmi, data, regs);
+ if (event->fasync && event->pending_kill) {
+ if (nmi) {
+ event->pending_wakeup = 1;
+ irq_work_queue(&event->pending);
+ } else
+ perf_event_wakeup(event);
+ }
+
return ret;
}
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 74d1c09..fa27e75 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -105,9 +105,12 @@ static int __jump_label_text_reserved(struct jump_entry *iter_start,
}
static void __jump_label_update(struct jump_label_key *key,
- struct jump_entry *entry, int enable)
+ struct jump_entry *entry,
+ struct jump_entry *stop, int enable)
{
- for (; entry->key == (jump_label_t)(unsigned long)key; entry++) {
+ for (; (entry < stop) &&
+ (entry->key == (jump_label_t)(unsigned long)key);
+ entry++) {
/*
* entry->code set to 0 invalidates module init text sections
* kernel_text_address() verifies we are not in core kernel
@@ -181,7 +184,11 @@ static void __jump_label_mod_update(struct jump_label_key *key, int enable)
struct jump_label_mod *mod = key->next;
while (mod) {
- __jump_label_update(key, mod->entries, enable);
+ struct module *m = mod->mod;
+
+ __jump_label_update(key, mod->entries,
+ m->jump_entries + m->num_jump_entries,
+ enable);
mod = mod->next;
}
}
@@ -245,7 +252,8 @@ static int jump_label_add_module(struct module *mod)
key->next = jlm;
if (jump_label_enabled(key))
- __jump_label_update(key, iter, JUMP_LABEL_ENABLE);
+ __jump_label_update(key, iter, iter_stop,
+ JUMP_LABEL_ENABLE);
}
return 0;
@@ -371,7 +379,7 @@ static void jump_label_update(struct jump_label_key *key, int enable)
/* if there are no users, entry can be NULL */
if (entry)
- __jump_label_update(key, entry, enable);
+ __jump_label_update(key, entry, __stop___jump_table, enable);
#ifdef CONFIG_MODULES
__jump_label_mod_update(key, enable);
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index beb1846..fd8d1e0 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -40,6 +40,7 @@
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/init.h>
+#include <linux/kernel.h>
#include <linux/uaccess.h>
@@ -404,24 +405,36 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
size_t count, loff_t *f_pos)
{
s32 value;
- int x;
- char ascii_value[11];
struct pm_qos_request_list *pm_qos_req;
if (count == sizeof(s32)) {
if (copy_from_user(&value, buf, sizeof(s32)))
return -EFAULT;
- } else if (count == 11) { /* len('0x12345678/0') */
- if (copy_from_user(ascii_value, buf, 11))
+ } else if (count <= 11) { /* ASCII perhaps? */
+ char ascii_value[11];
+ unsigned long int ulval;
+ int ret;
+
+ if (copy_from_user(ascii_value, buf, count))
return -EFAULT;
- if (strlen(ascii_value) != 10)
- return -EINVAL;
- x = sscanf(ascii_value, "%x", &value);
- if (x != 1)
+
+ if (count > 10) {
+ if (ascii_value[10] == '\n')
+ ascii_value[10] = '\0';
+ else
+ return -EINVAL;
+ } else {
+ ascii_value[count] = '\0';
+ }
+ ret = strict_strtoul(ascii_value, 16, &ulval);
+ if (ret) {
+ pr_debug("%s, 0x%lx, 0x%x\n", ascii_value, ulval, ret);
return -EINVAL;
- pr_debug("%s, %d, 0x%x\n", ascii_value, x, value);
- } else
+ }
+ value = (s32)lower_32_bits(ulval);
+ } else {
return -EINVAL;
+ }
pm_qos_req = filp->private_data;
pm_qos_update_request(pm_qos_req, value);
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index f9bec56..8f7b1db 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -25,7 +25,6 @@
#include <linux/gfp.h>
#include <linux/syscore_ops.h>
#include <scsi/scsi_scan.h>
-#include <asm/suspend.h>
#include "power.h"
@@ -55,10 +54,9 @@ static int hibernation_mode = HIBERNATION_SHUTDOWN;
static const struct platform_hibernation_ops *hibernation_ops;
/**
- * hibernation_set_ops - set the global hibernate operations
- * @ops: the hibernation operations to use in subsequent hibernation transitions
+ * hibernation_set_ops - Set the global hibernate operations.
+ * @ops: Hibernation operations to use in subsequent hibernation transitions.
*/
-
void hibernation_set_ops(const struct platform_hibernation_ops *ops)
{
if (ops && !(ops->begin && ops->end && ops->pre_snapshot
@@ -115,10 +113,9 @@ static int hibernation_test(int level) { return 0; }
#endif /* !CONFIG_PM_DEBUG */
/**
- * platform_begin - tell the platform driver that we're starting
- * hibernation
+ * platform_begin - Call platform to start hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
*/
-
static int platform_begin(int platform_mode)
{
return (platform_mode && hibernation_ops) ?
@@ -126,10 +123,9 @@ static int platform_begin(int platform_mode)
}
/**
- * platform_end - tell the platform driver that we've entered the
- * working state
+ * platform_end - Call platform to finish transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
*/
-
static void platform_end(int platform_mode)
{
if (platform_mode && hibernation_ops)
@@ -137,8 +133,11 @@ static void platform_end(int platform_mode)
}
/**
- * platform_pre_snapshot - prepare the machine for hibernation using the
- * platform driver if so configured and return an error code if it fails
+ * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for creating a hibernate image,
+ * if so configured, and return an error code if that fails.
*/
static int platform_pre_snapshot(int platform_mode)
@@ -148,10 +147,14 @@ static int platform_pre_snapshot(int platform_mode)
}
/**
- * platform_leave - prepare the machine for switching to the normal mode
- * of operation using the platform driver (called with interrupts disabled)
+ * platform_leave - Call platform to prepare a transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver prepare to prepare the machine for switching to the
+ * normal mode of operation.
+ *
+ * This routine is called on one CPU with interrupts disabled.
*/
-
static void platform_leave(int platform_mode)
{
if (platform_mode && hibernation_ops)
@@ -159,10 +162,14 @@ static void platform_leave(int platform_mode)
}
/**
- * platform_finish - switch the machine to the normal mode of operation
- * using the platform driver (must be called after platform_prepare())
+ * platform_finish - Call platform to switch the system to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the machine to the normal mode of
+ * operation.
+ *
+ * This routine must be called after platform_prepare().
*/
-
static void platform_finish(int platform_mode)
{
if (platform_mode && hibernation_ops)
@@ -170,11 +177,15 @@ static void platform_finish(int platform_mode)
}
/**
- * platform_pre_restore - prepare the platform for the restoration from a
- * hibernation image. If the restore fails after this function has been
- * called, platform_restore_cleanup() must be called.
+ * platform_pre_restore - Prepare for hibernate image restoration.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for resume from a hibernation
+ * image.
+ *
+ * If the restore fails after this function has been called,
+ * platform_restore_cleanup() must be called.
*/
-
static int platform_pre_restore(int platform_mode)
{
return (platform_mode && hibernation_ops) ?
@@ -182,12 +193,16 @@ static int platform_pre_restore(int platform_mode)
}
/**
- * platform_restore_cleanup - switch the platform to the normal mode of
- * operation after a failing restore. If platform_pre_restore() has been
- * called before the failing restore, this function must be called too,
- * regardless of the result of platform_pre_restore().
+ * platform_restore_cleanup - Switch to the working state after failing restore.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the system to the normal mode of operation
+ * after a failing restore.
+ *
+ * If platform_pre_restore() has been called before the failing restore, this
+ * function must be called too, regardless of the result of
+ * platform_pre_restore().
*/
-
static void platform_restore_cleanup(int platform_mode)
{
if (platform_mode && hibernation_ops)
@@ -195,10 +210,9 @@ static void platform_restore_cleanup(int platform_mode)
}
/**
- * platform_recover - recover the platform from a failure to suspend
- * devices.
+ * platform_recover - Recover from a failure to suspend devices.
+ * @platform_mode: Whether or not to use the platform driver.
*/
-
static void platform_recover(int platform_mode)
{
if (platform_mode && hibernation_ops && hibernation_ops->recover)
@@ -206,13 +220,12 @@ static void platform_recover(int platform_mode)
}
/**
- * swsusp_show_speed - print the time elapsed between two events.
- * @start: Starting event.
- * @stop: Final event.
- * @nr_pages - number of pages processed between @start and @stop
- * @msg - introductory message to print
+ * swsusp_show_speed - Print time elapsed between two events during hibernation.
+ * @start: Starting event.
+ * @stop: Final event.
+ * @nr_pages: Number of memory pages processed between @start and @stop.
+ * @msg: Additional diagnostic message to print.
*/
-
void swsusp_show_speed(struct timeval *start, struct timeval *stop,
unsigned nr_pages, char *msg)
{
@@ -235,25 +248,18 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop,
}
/**
- * create_image - freeze devices that need to be frozen with interrupts
- * off, create the hibernation image and thaw those devices. Control
- * reappears in this routine after a restore.
+ * create_image - Create a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' .freeze_noirq() callbacks, create a hibernation image
+ * and execute the drivers' .thaw_noirq() callbacks.
+ *
+ * Control reappears in this routine after the subsequent restore.
*/
-
static int create_image(int platform_mode)
{
int error;
- error = arch_prepare_suspend();
- if (error)
- return error;
-
- /* At this point, dpm_suspend_start() has been called, but *not*
- * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now.
- * Otherwise, drivers for some devices (e.g. interrupt controllers)
- * become desynchronized with the actual state of the hardware
- * at resume time, and evil weirdness ensues.
- */
error = dpm_suspend_noirq(PMSG_FREEZE);
if (error) {
printk(KERN_ERR "PM: Some devices failed to power down, "
@@ -297,9 +303,6 @@ static int create_image(int platform_mode)
Power_up:
syscore_resume();
- /* NOTE: dpm_resume_noirq() is just a resume() for devices
- * that suspended with irqs off ... no overall powerup.
- */
Enable_irqs:
local_irq_enable();
@@ -317,14 +320,11 @@ static int create_image(int platform_mode)
}
/**
- * hibernation_snapshot - quiesce devices and create the hibernation
- * snapshot image.
- * @platform_mode - if set, use the platform driver, if available, to
- * prepare the platform firmware for the power transition.
+ * hibernation_snapshot - Quiesce devices and create a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
*
- * Must be called with pm_mutex held
+ * This routine must be called with pm_mutex held.
*/
-
int hibernation_snapshot(int platform_mode)
{
pm_message_t msg = PMSG_RECOVER;
@@ -384,13 +384,14 @@ int hibernation_snapshot(int platform_mode)
}
/**
- * resume_target_kernel - prepare devices that need to be suspended with
- * interrupts off, restore the contents of highmem that have not been
- * restored yet from the image and run the low level code that will restore
- * the remaining contents of memory and switch to the just restored target
- * kernel.
+ * resume_target_kernel - Restore system state from a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' .freeze_noirq() callbacks, restore the contents of
+ * highmem that have not been restored yet from the image and run the low-level
+ * code that will restore the remaining contents of memory and switch to the
+ * just restored target kernel.
*/
-
static int resume_target_kernel(bool platform_mode)
{
int error;
@@ -416,24 +417,26 @@ static int resume_target_kernel(bool platform_mode)
if (error)
goto Enable_irqs;
- /* We'll ignore saved state, but this gets preempt count (etc) right */
save_processor_state();
error = restore_highmem();
if (!error) {
error = swsusp_arch_resume();
/*
* The code below is only ever reached in case of a failure.
- * Otherwise execution continues at place where
- * swsusp_arch_suspend() was called
+ * Otherwise, execution continues at the place where
+ * swsusp_arch_suspend() was called.
*/
BUG_ON(!error);
- /* This call to restore_highmem() undos the previous one */
+ /*
+ * This call to restore_highmem() reverts the changes made by
+ * the previous one.
+ */
restore_highmem();
}
/*
* The only reason why swsusp_arch_resume() can fail is memory being
* very tight, so we have to free it as soon as we can to avoid
- * subsequent failures
+ * subsequent failures.
*/
swsusp_free();
restore_processor_state();
@@ -456,14 +459,12 @@ static int resume_target_kernel(bool platform_mode)
}
/**
- * hibernation_restore - quiesce devices and restore the hibernation
- * snapshot image. If successful, control returns in hibernation_snaphot()
- * @platform_mode - if set, use the platform driver, if available, to
- * prepare the platform firmware for the transition.
+ * hibernation_restore - Quiesce devices and restore from a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
*
- * Must be called with pm_mutex held
+ * This routine must be called with pm_mutex held. If it is successful, control
+ * reappears in the restored target kernel in hibernation_snaphot().
*/
-
int hibernation_restore(int platform_mode)
{
int error;
@@ -483,10 +484,8 @@ int hibernation_restore(int platform_mode)
}
/**
- * hibernation_platform_enter - enter the hibernation state using the
- * platform driver (if available)
+ * hibernation_platform_enter - Power off the system using the platform driver.
*/
-
int hibernation_platform_enter(void)
{
int error;
@@ -557,12 +556,12 @@ int hibernation_platform_enter(void)
}
/**
- * power_down - Shut the machine down for hibernation.
+ * power_down - Shut the machine down for hibernation.
*
- * Use the platform driver, if configured so; otherwise try
- * to power off or reboot.
+ * Use the platform driver, if configured, to put the system into the sleep
+ * state corresponding to hibernation, or try to power it off or reboot,
+ * depending on the value of hibernation_mode.
*/
-
static void power_down(void)
{
switch (hibernation_mode) {
@@ -599,9 +598,8 @@ static int prepare_processes(void)
}
/**
- * hibernate - The granpappy of the built-in hibernation management
+ * hibernate - Carry out system hibernation, including saving the image.
*/
-
int hibernate(void)
{
int error;
@@ -679,17 +677,20 @@ int hibernate(void)
/**
- * software_resume - Resume from a saved image.
+ * software_resume - Resume from a saved hibernation image.
*
- * Called as a late_initcall (so all devices are discovered and
- * initialized), we call swsusp to see if we have a saved image or not.
- * If so, we quiesce devices, the restore the saved image. We will
- * return above (in hibernate() ) if everything goes well.
- * Otherwise, we fail gracefully and return to the normally
- * scheduled program.
+ * This routine is called as a late initcall, when all devices have been
+ * discovered and initialized already.
*
+ * The image reading code is called to see if there is a hibernation image
+ * available for reading. If that is the case, devices are quiesced and the
+ * contents of memory is restored from the saved image.
+ *
+ * If this is successful, control reappears in the restored target kernel in
+ * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine
+ * attempts to recover gracefully and make the kernel return to the normal mode
+ * of operation.
*/
-
static int software_resume(void)
{
int error;
@@ -819,21 +820,17 @@ static const char * const hibernation_modes[] = {
[HIBERNATION_TESTPROC] = "testproc",
};
-/**
- * disk - Control hibernation mode
- *
- * Suspend-to-disk can be handled in several ways. We have a few options
- * for putting the system to sleep - using the platform driver (e.g. ACPI
- * or other hibernation_ops), powering off the system or rebooting the
- * system (for testing) as well as the two test modes.
+/*
+ * /sys/power/disk - Control hibernation mode.
*
- * The system can support 'platform', and that is known a priori (and
- * encoded by the presence of hibernation_ops). However, the user may
- * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
- * test modes, 'test' or 'testproc'.
+ * Hibernation can be handled in several ways. There are a few different ways
+ * to put the system into the sleep state: using the platform driver (e.g. ACPI
+ * or other hibernation_ops), powering it off or rebooting it (for testing
+ * mostly), or using one of the two available test modes.
*
- * show() will display what the mode is currently set to.
- * store() will accept one of
+ * The sysfs file /sys/power/disk provides an interface for selecting the
+ * hibernation mode to use. Reading from this file causes the available modes
+ * to be printed. There are 5 modes that can be supported:
*
* 'platform'
* 'shutdown'
@@ -841,8 +838,14 @@ static const char * const hibernation_modes[] = {
* 'test'
* 'testproc'
*
- * It will only change to 'platform' if the system
- * supports it (as determined by having hibernation_ops).
+ * If a platform hibernation driver is in use, 'platform' will be supported
+ * and will be used by default. Otherwise, 'shutdown' will be used by default.
+ * The selected option (i.e. the one corresponding to the current value of
+ * hibernation_mode) is enclosed by a square bracket.
+ *
+ * To select a given hibernation mode it is necessary to write the mode's
+ * string representation (as returned by reading from /sys/power/disk) back
+ * into /sys/power/disk.
*/
static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
@@ -875,7 +878,6 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
return buf-start;
}
-
static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t n)
{
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index f07d2f0..77a7671 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -36,7 +36,7 @@
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/nmi.h>
-#include <asm/atomic.h>
+#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/completion.h>
@@ -95,7 +95,6 @@ static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
-static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq);
DEFINE_PER_CPU(char, rcu_cpu_has_work);
static char rcu_kthreads_spawnable;
@@ -163,7 +162,7 @@ EXPORT_SYMBOL_GPL(rcu_note_context_switch);
#ifdef CONFIG_NO_HZ
DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = {
.dynticks_nesting = 1,
- .dynticks = 1,
+ .dynticks = ATOMIC_INIT(1),
};
#endif /* #ifdef CONFIG_NO_HZ */
@@ -322,13 +321,25 @@ void rcu_enter_nohz(void)
unsigned long flags;
struct rcu_dynticks *rdtp;
- smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
local_irq_save(flags);
rdtp = &__get_cpu_var(rcu_dynticks);
- rdtp->dynticks++;
- rdtp->dynticks_nesting--;
- WARN_ON_ONCE(rdtp->dynticks & 0x1);
+ if (--rdtp->dynticks_nesting) {
+ local_irq_restore(flags);
+ return;
+ }
+ /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */
+ smp_mb__before_atomic_inc(); /* See above. */
+ atomic_inc(&rdtp->dynticks);
+ smp_mb__after_atomic_inc(); /* Force ordering with next sojourn. */
+ WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1);
local_irq_restore(flags);
+
+ /* If the interrupt queued a callback, get out of dyntick mode. */
+ if (in_irq() &&
+ (__get_cpu_var(rcu_sched_data).nxtlist ||
+ __get_cpu_var(rcu_bh_data).nxtlist ||
+ rcu_preempt_needs_cpu(smp_processor_id())))
+ set_need_resched();
}
/*
@@ -344,11 +355,16 @@ void rcu_exit_nohz(void)
local_irq_save(flags);
rdtp = &__get_cpu_var(rcu_dynticks);
- rdtp->dynticks++;
- rdtp->dynticks_nesting++;
- WARN_ON_ONCE(!(rdtp->dynticks & 0x1));
+ if (rdtp->dynticks_nesting++) {
+ local_irq_restore(flags);
+ return;
+ }
+ smp_mb__before_atomic_inc(); /* Force ordering w/previous sojourn. */
+ atomic_inc(&rdtp->dynticks);
+ /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */
+ smp_mb__after_atomic_inc(); /* See above. */
+ WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1));
local_irq_restore(flags);
- smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
}
/**
@@ -362,11 +378,15 @@ void rcu_nmi_enter(void)
{
struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks);
- if (rdtp->dynticks & 0x1)
+ if (rdtp->dynticks_nmi_nesting == 0 &&
+ (atomic_read(&rdtp->dynticks) & 0x1))
return;
- rdtp->dynticks_nmi++;
- WARN_ON_ONCE(!(rdtp->dynticks_nmi & 0x1));
- smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
+ rdtp->dynticks_nmi_nesting++;
+ smp_mb__before_atomic_inc(); /* Force delay from prior write. */
+ atomic_inc(&rdtp->dynticks);
+ /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */
+ smp_mb__after_atomic_inc(); /* See above. */
+ WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1));
}
/**
@@ -380,11 +400,14 @@ void rcu_nmi_exit(void)
{
struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks);
- if (rdtp->dynticks & 0x1)
+ if (rdtp->dynticks_nmi_nesting == 0 ||
+ --rdtp->dynticks_nmi_nesting != 0)
return;
- smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
- rdtp->dynticks_nmi++;
- WARN_ON_ONCE(rdtp->dynticks_nmi & 0x1);
+ /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */
+ smp_mb__before_atomic_inc(); /* See above. */
+ atomic_inc(&rdtp->dynticks);
+ smp_mb__after_atomic_inc(); /* Force delay to next write. */
+ WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1);
}
/**
@@ -395,13 +418,7 @@ void rcu_nmi_exit(void)
*/
void rcu_irq_enter(void)
{
- struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks);
-
- if (rdtp->dynticks_nesting++)
- return;
- rdtp->dynticks++;
- WARN_ON_ONCE(!(rdtp->dynticks & 0x1));
- smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
+ rcu_exit_nohz();
}
/**
@@ -413,18 +430,7 @@ void rcu_irq_enter(void)
*/
void rcu_irq_exit(void)
{
- struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks);
-
- if (--rdtp->dynticks_nesting)
- return;
- smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
- rdtp->dynticks++;
- WARN_ON_ONCE(rdtp->dynticks & 0x1);
-
- /* If the interrupt queued a callback, get out of dyntick mode. */
- if (__this_cpu_read(rcu_sched_data.nxtlist) ||
- __this_cpu_read(rcu_bh_data.nxtlist))
- set_need_resched();
+ rcu_enter_nohz();
}
#ifdef CONFIG_SMP
@@ -436,19 +442,8 @@ void rcu_irq_exit(void)
*/
static int dyntick_save_progress_counter(struct rcu_data *rdp)
{
- int ret;
- int snap;
- int snap_nmi;
-
- snap = rdp->dynticks->dynticks;
- snap_nmi = rdp->dynticks->dynticks_nmi;
- smp_mb(); /* Order sampling of snap with end of grace period. */
- rdp->dynticks_snap = snap;
- rdp->dynticks_nmi_snap = snap_nmi;
- ret = ((snap & 0x1) == 0) && ((snap_nmi & 0x1) == 0);
- if (ret)
- rdp->dynticks_fqs++;
- return ret;
+ rdp->dynticks_snap = atomic_add_return(0, &rdp->dynticks->dynticks);
+ return 0;
}
/*
@@ -459,16 +454,11 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp)
*/
static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
{
- long curr;
- long curr_nmi;
- long snap;
- long snap_nmi;
+ unsigned long curr;
+ unsigned long snap;
- curr = rdp->dynticks->dynticks;
- snap = rdp->dynticks_snap;
- curr_nmi = rdp->dynticks->dynticks_nmi;
- snap_nmi = rdp->dynticks_nmi_snap;
- smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
+ curr = (unsigned long)atomic_add_return(0, &rdp->dynticks->dynticks);
+ snap = (unsigned long)rdp->dynticks_snap;
/*
* If the CPU passed through or entered a dynticks idle phase with
@@ -478,8 +468,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
* read-side critical section that started before the beginning
* of the current RCU grace period.
*/
- if ((curr != snap || (curr & 0x1) == 0) &&
- (curr_nmi != snap_nmi || (curr_nmi & 0x1) == 0)) {
+ if ((curr & 0x1) == 0 || ULONG_CMP_GE(curr, snap + 2)) {
rdp->dynticks_fqs++;
return 1;
}
@@ -908,6 +897,12 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
unsigned long gp_duration;
WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
+
+ /*
+ * Ensure that all grace-period and pre-grace-period activity
+ * is seen before the assignment to rsp->completed.
+ */
+ smp_mb(); /* See above block comment. */
gp_duration = jiffies - rsp->gp_start;
if (gp_duration > rsp->gp_max)
rsp->gp_max = gp_duration;
@@ -1455,25 +1450,11 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
*/
static void rcu_process_callbacks(void)
{
- /*
- * Memory references from any prior RCU read-side critical sections
- * executed by the interrupted code must be seen before any RCU
- * grace-period manipulations below.
- */
- smp_mb(); /* See above block comment. */
-
__rcu_process_callbacks(&rcu_sched_state,
&__get_cpu_var(rcu_sched_data));
__rcu_process_callbacks(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
rcu_preempt_process_callbacks();
- /*
- * Memory references from any later RCU read-side critical sections
- * executed by the interrupted code must be seen after any RCU
- * grace-period manipulations above.
- */
- smp_mb(); /* See above block comment. */
-
/* If we are last CPU on way to dyntick-idle mode, accelerate it. */
rcu_needs_cpu_flush();
}
@@ -1494,7 +1475,7 @@ static void invoke_rcu_cpu_kthread(void)
local_irq_restore(flags);
return;
}
- wake_up(&__get_cpu_var(rcu_cpu_wq));
+ wake_up_process(__this_cpu_read(rcu_cpu_kthread_task));
local_irq_restore(flags);
}
@@ -1544,13 +1525,10 @@ static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
*/
static void rcu_cpu_kthread_timer(unsigned long arg)
{
- unsigned long flags;
struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
struct rcu_node *rnp = rdp->mynode;
- raw_spin_lock_irqsave(&rnp->lock, flags);
- rnp->wakemask |= rdp->grpmask;
- raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ atomic_or(rdp->grpmask, &rnp->wakemask);
invoke_rcu_node_kthread(rnp);
}
@@ -1617,14 +1595,12 @@ static int rcu_cpu_kthread(void *arg)
unsigned long flags;
int spincnt = 0;
unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
- wait_queue_head_t *wqp = &per_cpu(rcu_cpu_wq, cpu);
char work;
char *workp = &per_cpu(rcu_cpu_has_work, cpu);
for (;;) {
*statusp = RCU_KTHREAD_WAITING;
- wait_event_interruptible(*wqp,
- *workp != 0 || kthread_should_stop());
+ rcu_wait(*workp != 0 || kthread_should_stop());
local_bh_disable();
if (rcu_cpu_kthread_should_stop(cpu)) {
local_bh_enable();
@@ -1672,10 +1648,10 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
if (IS_ERR(t))
return PTR_ERR(t);
kthread_bind(t, cpu);
+ set_task_state(t, TASK_INTERRUPTIBLE);
per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
per_cpu(rcu_cpu_kthread_task, cpu) = t;
- wake_up_process(t);
sp.sched_priority = RCU_KTHREAD_PRIO;
sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
return 0;
@@ -1698,11 +1674,10 @@ static int rcu_node_kthread(void *arg)
for (;;) {
rnp->node_kthread_status = RCU_KTHREAD_WAITING;
- wait_event_interruptible(rnp->node_wq, rnp->wakemask != 0);
+ rcu_wait(atomic_read(&rnp->wakemask) != 0);
rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
raw_spin_lock_irqsave(&rnp->lock, flags);
- mask = rnp->wakemask;
- rnp->wakemask = 0;
+ mask = atomic_xchg(&rnp->wakemask, 0);
rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
if ((mask & 0x1) == 0)
@@ -1781,9 +1756,9 @@ static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
if (IS_ERR(t))
return PTR_ERR(t);
raw_spin_lock_irqsave(&rnp->lock, flags);
+ set_task_state(t, TASK_INTERRUPTIBLE);
rnp->node_kthread_task = t;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
- wake_up_process(t);
sp.sched_priority = 99;
sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
}
@@ -1800,21 +1775,16 @@ static int __init rcu_spawn_kthreads(void)
rcu_kthreads_spawnable = 1;
for_each_possible_cpu(cpu) {
- init_waitqueue_head(&per_cpu(rcu_cpu_wq, cpu));
per_cpu(rcu_cpu_has_work, cpu) = 0;
if (cpu_online(cpu))
(void)rcu_spawn_one_cpu_kthread(cpu);
}
rnp = rcu_get_root(rcu_state);
- init_waitqueue_head(&rnp->node_wq);
- rcu_init_boost_waitqueue(rnp);
(void)rcu_spawn_one_node_kthread(rcu_state, rnp);
- if (NUM_RCU_NODES > 1)
- rcu_for_each_leaf_node(rcu_state, rnp) {
- init_waitqueue_head(&rnp->node_wq);
- rcu_init_boost_waitqueue(rnp);
+ if (NUM_RCU_NODES > 1) {
+ rcu_for_each_leaf_node(rcu_state, rnp)
(void)rcu_spawn_one_node_kthread(rcu_state, rnp);
- }
+ }
return 0;
}
early_initcall(rcu_spawn_kthreads);
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 2576648..7b9a08b 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -84,11 +84,9 @@
* Dynticks per-CPU state.
*/
struct rcu_dynticks {
- int dynticks_nesting; /* Track nesting level, sort of. */
- int dynticks; /* Even value for dynticks-idle, else odd. */
- int dynticks_nmi; /* Even value for either dynticks-idle or */
- /* not in nmi handler, else odd. So this */
- /* remains even for nmi from irq handler. */
+ int dynticks_nesting; /* Track irq/process nesting level. */
+ int dynticks_nmi_nesting; /* Track NMI nesting level. */
+ atomic_t dynticks; /* Even value for dynticks-idle, else odd. */
};
/* RCU's kthread states for tracing. */
@@ -121,7 +119,9 @@ struct rcu_node {
/* elements that need to drain to allow the */
/* current expedited grace period to */
/* complete (only for TREE_PREEMPT_RCU). */
- unsigned long wakemask; /* CPUs whose kthread needs to be awakened. */
+ atomic_t wakemask; /* CPUs whose kthread needs to be awakened. */
+ /* Since this has meaning only for leaf */
+ /* rcu_node structures, 32 bits suffices. */
unsigned long qsmaskinit;
/* Per-GP initial value for qsmask & expmask. */
unsigned long grpmask; /* Mask to apply to parent qsmask. */
@@ -159,9 +159,6 @@ struct rcu_node {
struct task_struct *boost_kthread_task;
/* kthread that takes care of priority */
/* boosting for this rcu_node structure. */
- wait_queue_head_t boost_wq;
- /* Wait queue on which to park the boost */
- /* kthread. */
unsigned int boost_kthread_status;
/* State of boost_kthread_task for tracing. */
unsigned long n_tasks_boosted;
@@ -188,9 +185,6 @@ struct rcu_node {
/* kthread that takes care of this rcu_node */
/* structure, for example, awakening the */
/* per-CPU kthreads as needed. */
- wait_queue_head_t node_wq;
- /* Wait queue on which to park the per-node */
- /* kthread. */
unsigned int node_kthread_status;
/* State of node_kthread_task for tracing. */
} ____cacheline_internodealigned_in_smp;
@@ -284,7 +278,6 @@ struct rcu_data {
/* 3) dynticks interface. */
struct rcu_dynticks *dynticks; /* Shared per-CPU dynticks state. */
int dynticks_snap; /* Per-GP tracking for dynticks. */
- int dynticks_nmi_snap; /* Per-GP tracking for dynticks_nmi. */
#endif /* #ifdef CONFIG_NO_HZ */
/* 4) reasons this CPU needed to be kicked by force_quiescent_state */
@@ -337,6 +330,16 @@ struct rcu_data {
/* scheduling clock irq */
/* before ratting on them. */
+#define rcu_wait(cond) \
+do { \
+ for (;;) { \
+ set_current_state(TASK_INTERRUPTIBLE); \
+ if (cond) \
+ break; \
+ schedule(); \
+ } \
+ __set_current_state(TASK_RUNNING); \
+} while (0)
/*
* RCU global state, including node hierarchy. This hierarchy is
@@ -446,7 +449,6 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
static void rcu_preempt_send_cbs_to_online(void);
static void __init __rcu_init_preempt(void);
static void rcu_needs_cpu_flush(void);
-static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp);
static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
cpumask_var_t cm);
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 3f6559a..a767b7d 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -1196,8 +1196,7 @@ static int rcu_boost_kthread(void *arg)
for (;;) {
rnp->boost_kthread_status = RCU_KTHREAD_WAITING;
- wait_event_interruptible(rnp->boost_wq, rnp->boost_tasks ||
- rnp->exp_tasks);
+ rcu_wait(rnp->boost_tasks || rnp->exp_tasks);
rnp->boost_kthread_status = RCU_KTHREAD_RUNNING;
more2boost = rcu_boost(rnp);
if (more2boost)
@@ -1275,14 +1274,6 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
}
/*
- * Initialize the RCU-boost waitqueue.
- */
-static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp)
-{
- init_waitqueue_head(&rnp->boost_wq);
-}
-
-/*
* Create an RCU-boost kthread for the specified node if one does not
* already exist. We only create this kthread for preemptible RCU.
* Returns zero if all is well, a negated errno otherwise.
@@ -1304,9 +1295,9 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
if (IS_ERR(t))
return PTR_ERR(t);
raw_spin_lock_irqsave(&rnp->lock, flags);
+ set_task_state(t, TASK_INTERRUPTIBLE);
rnp->boost_kthread_task = t;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
- wake_up_process(t);
sp.sched_priority = RCU_KTHREAD_PRIO;
sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
return 0;
@@ -1328,10 +1319,6 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
{
}
-static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp)
-{
-}
-
static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
struct rcu_node *rnp,
int rnp_index)
@@ -1520,7 +1507,6 @@ int rcu_needs_cpu(int cpu)
{
int c = 0;
int snap;
- int snap_nmi;
int thatcpu;
/* Check for being in the holdoff period. */
@@ -1531,10 +1517,10 @@ int rcu_needs_cpu(int cpu)
for_each_online_cpu(thatcpu) {
if (thatcpu == cpu)
continue;
- snap = per_cpu(rcu_dynticks, thatcpu).dynticks;
- snap_nmi = per_cpu(rcu_dynticks, thatcpu).dynticks_nmi;
+ snap = atomic_add_return(0, &per_cpu(rcu_dynticks,
+ thatcpu).dynticks);
smp_mb(); /* Order sampling of snap with end of grace period. */
- if (((snap & 0x1) != 0) || ((snap_nmi & 0x1) != 0)) {
+ if ((snap & 0x1) != 0) {
per_cpu(rcu_dyntick_drain, cpu) = 0;
per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1;
return rcu_needs_cpu_quick_check(cpu);
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index aa0fd72..9678cc3 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -69,10 +69,10 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
rdp->passed_quiesc, rdp->passed_quiesc_completed,
rdp->qs_pending);
#ifdef CONFIG_NO_HZ
- seq_printf(m, " dt=%d/%d dn=%d df=%lu",
- rdp->dynticks->dynticks,
+ seq_printf(m, " dt=%d/%d/%d df=%lu",
+ atomic_read(&rdp->dynticks->dynticks),
rdp->dynticks->dynticks_nesting,
- rdp->dynticks->dynticks_nmi,
+ rdp->dynticks->dynticks_nmi_nesting,
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
@@ -141,9 +141,9 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
rdp->qs_pending);
#ifdef CONFIG_NO_HZ
seq_printf(m, ",%d,%d,%d,%lu",
- rdp->dynticks->dynticks,
+ atomic_read(&rdp->dynticks->dynticks),
rdp->dynticks->dynticks_nesting,
- rdp->dynticks->dynticks_nmi,
+ rdp->dynticks->dynticks_nmi_nesting,
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
@@ -167,7 +167,7 @@ static int show_rcudata_csv(struct seq_file *m, void *unused)
{
seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");
#ifdef CONFIG_NO_HZ
- seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
+ seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
#endif /* #ifdef CONFIG_NO_HZ */
seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\",\"ci\",\"co\",\"ca\"\n");
#ifdef CONFIG_TREE_PREEMPT_RCU
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index d017c2c..1ee417f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -109,12 +109,18 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip);
static void ftrace_global_list_func(unsigned long ip,
unsigned long parent_ip)
{
- struct ftrace_ops *op = rcu_dereference_raw(ftrace_global_list); /*see above*/
+ struct ftrace_ops *op;
+
+ if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT)))
+ return;
+ trace_recursion_set(TRACE_GLOBAL_BIT);
+ op = rcu_dereference_raw(ftrace_global_list); /*see above*/
while (op != &ftrace_list_end) {
op->func(ip, parent_ip);
op = rcu_dereference_raw(op->next); /*see above*/
};
+ trace_recursion_clear(TRACE_GLOBAL_BIT);
}
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip)
@@ -1638,12 +1644,12 @@ static void ftrace_startup_enable(int command)
ftrace_run_update_code(command);
}
-static void ftrace_startup(struct ftrace_ops *ops, int command)
+static int ftrace_startup(struct ftrace_ops *ops, int command)
{
bool hash_enable = true;
if (unlikely(ftrace_disabled))
- return;
+ return -ENODEV;
ftrace_start_up++;
command |= FTRACE_ENABLE_CALLS;
@@ -1662,6 +1668,8 @@ static void ftrace_startup(struct ftrace_ops *ops, int command)
ftrace_hash_rec_enable(ops, 1);
ftrace_startup_enable(command);
+
+ return 0;
}
static void ftrace_shutdown(struct ftrace_ops *ops, int command)
@@ -2501,7 +2509,7 @@ static void __enable_ftrace_function_probe(void)
ret = __register_ftrace_function(&trace_probe_ops);
if (!ret)
- ftrace_startup(&trace_probe_ops, 0);
+ ret = ftrace_startup(&trace_probe_ops, 0);
ftrace_probe_registered = 1;
}
@@ -3466,7 +3474,11 @@ device_initcall(ftrace_nodyn_init);
static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
static inline void ftrace_startup_enable(int command) { }
/* Keep as macros so we do not need to define the commands */
-# define ftrace_startup(ops, command) do { } while (0)
+# define ftrace_startup(ops, command) \
+ ({ \
+ (ops)->flags |= FTRACE_OPS_FL_ENABLED; \
+ 0; \
+ })
# define ftrace_shutdown(ops, command) do { } while (0)
# define ftrace_startup_sysctl() do { } while (0)
# define ftrace_shutdown_sysctl() do { } while (0)
@@ -3484,6 +3496,10 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
{
struct ftrace_ops *op;
+ if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT)))
+ return;
+
+ trace_recursion_set(TRACE_INTERNAL_BIT);
/*
* Some of the ops may be dynamically allocated,
* they must be freed after a synchronize_sched().
@@ -3496,6 +3512,7 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
op = rcu_dereference_raw(op->next);
};
preempt_enable_notrace();
+ trace_recursion_clear(TRACE_INTERNAL_BIT);
}
static void clear_ftrace_swapper(void)
@@ -3799,7 +3816,7 @@ int register_ftrace_function(struct ftrace_ops *ops)
ret = __register_ftrace_function(ops);
if (!ret)
- ftrace_startup(ops, 0);
+ ret = ftrace_startup(ops, 0);
out_unlock:
@@ -4045,7 +4062,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_graph_return = retfunc;
ftrace_graph_entry = entryfunc;
- ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
+ ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_lock);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 0ef7b4b..b0c7aa4 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2216,7 +2216,7 @@ static noinline void trace_recursive_fail(void)
printk_once(KERN_WARNING "Tracing recursion: depth[%ld]:"
"HC[%lu]:SC[%lu]:NMI[%lu]\n",
- current->trace_recursion,
+ trace_recursion_buffer(),
hardirq_count() >> HARDIRQ_SHIFT,
softirq_count() >> SOFTIRQ_SHIFT,
in_nmi());
@@ -2226,9 +2226,9 @@ static noinline void trace_recursive_fail(void)
static inline int trace_recursive_lock(void)
{
- current->trace_recursion++;
+ trace_recursion_inc();
- if (likely(current->trace_recursion < TRACE_RECURSIVE_DEPTH))
+ if (likely(trace_recursion_buffer() < TRACE_RECURSIVE_DEPTH))
return 0;
trace_recursive_fail();
@@ -2238,9 +2238,9 @@ static inline int trace_recursive_lock(void)
static inline void trace_recursive_unlock(void)
{
- WARN_ON_ONCE(!current->trace_recursion);
+ WARN_ON_ONCE(!trace_recursion_buffer());
- current->trace_recursion--;
+ trace_recursion_dec();
}
#else
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 6b69c4b..229f859 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -784,4 +784,19 @@ extern const char *__stop___trace_bprintk_fmt[];
FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
#include "trace_entries.h"
+/* Only current can touch trace_recursion */
+#define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
+#define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
+
+/* Ring buffer has the 10 LSB bits to count */
+#define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
+
+/* for function tracing recursion */
+#define TRACE_INTERNAL_BIT (1<<11)
+#define TRACE_GLOBAL_BIT (1<<12)
+
+#define trace_recursion_set(bit) do { (current)->trace_recursion |= (bit); } while (0)
+#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(bit); } while (0)
+#define trace_recursion_test(bit) ((current)->trace_recursion & (bit))
+
#endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 2fe1103..686ec39 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1657,7 +1657,12 @@ static struct ftrace_ops trace_ops __initdata =
static __init void event_trace_self_test_with_function(void)
{
- register_ftrace_function(&trace_ops);
+ int ret;
+ ret = register_ftrace_function(&trace_ops);
+ if (WARN_ON(ret < 0)) {
+ pr_info("Failed to enable function tracer for event tests\n");
+ return;
+ }
pr_info("Running tests again, along with the function tracer\n");
event_trace_self_tests();
unregister_ftrace_function(&trace_ops);
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index cf535cc..e37de492 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -353,6 +353,33 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
}
EXPORT_SYMBOL(ftrace_print_symbols_seq);
+#if BITS_PER_LONG == 32
+const char *
+ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
+ const struct trace_print_flags_u64 *symbol_array)
+{
+ int i;
+ const char *ret = p->buffer + p->len;
+
+ for (i = 0; symbol_array[i].name; i++) {
+
+ if (val != symbol_array[i].mask)
+ continue;
+
+ trace_seq_puts(p, symbol_array[i].name);
+ break;
+ }
+
+ if (!p->len)
+ trace_seq_printf(p, "0x%llx", val);
+
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
+#endif
+
const char *
ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
{
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 7daa4b0..3d0c56a 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -415,15 +415,13 @@ static void watchdog_nmi_disable(int cpu) { return; }
#endif /* CONFIG_HARDLOCKUP_DETECTOR */
/* prepare/enable/disable routines */
-static int watchdog_prepare_cpu(int cpu)
+static void watchdog_prepare_cpu(int cpu)
{
struct hrtimer *hrtimer = &per_cpu(watchdog_hrtimer, cpu);
WARN_ON(per_cpu(softlockup_watchdog, cpu));
hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
hrtimer->function = watchdog_timer_fn;
-
- return 0;
}
static int watchdog_enable(int cpu)
@@ -542,17 +540,16 @@ static int __cpuinit
cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
int hotcpu = (unsigned long)hcpu;
- int err = 0;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
- err = watchdog_prepare_cpu(hotcpu);
+ watchdog_prepare_cpu(hotcpu);
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
if (watchdog_enabled)
- err = watchdog_enable(hotcpu);
+ watchdog_enable(hotcpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
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