tmp_suning_uos_patched/include/linux/stop_machine.h
Linus Torvalds d3ec4844d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  fs: Merge split strings
  treewide: fix potentially dangerous trailing ';' in #defined values/expressions
  uwb: Fix misspelling of neighbourhood in comment
  net, netfilter: Remove redundant goto in ebt_ulog_packet
  trivial: don't touch files that are removed in the staging tree
  lib/vsprintf: replace link to Draft by final RFC number
  doc: Kconfig: `to be' -> `be'
  doc: Kconfig: Typo: square -> squared
  doc: Konfig: Documentation/power/{pm => apm-acpi}.txt
  drivers/net: static should be at beginning of declaration
  drivers/media: static should be at beginning of declaration
  drivers/i2c: static should be at beginning of declaration
  XTENSA: static should be at beginning of declaration
  SH: static should be at beginning of declaration
  MIPS: static should be at beginning of declaration
  ARM: static should be at beginning of declaration
  rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check
  Update my e-mail address
  PCIe ASPM: forcedly -> forcibly
  gma500: push through device driver tree
  ...

Fix up trivial conflicts:
 - arch/arm/mach-ep93xx/dma-m2p.c (deleted)
 - drivers/gpio/gpio-ep93xx.c (renamed and context nearby)
 - drivers/net/r8169.c (just context changes)
2011-07-25 13:56:39 -07:00

157 lines
4.4 KiB
C

#ifndef _LINUX_STOP_MACHINE
#define _LINUX_STOP_MACHINE
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/list.h>
#include <asm/system.h>
/*
* stop_cpu[s]() is simplistic per-cpu maximum priority cpu
* monopolization mechanism. The caller can specify a non-sleeping
* function to be executed on a single or multiple cpus preempting all
* other processes and monopolizing those cpus until it finishes.
*
* Resources for this mechanism are preallocated when a cpu is brought
* up and requests are guaranteed to be served as long as the target
* cpus are online.
*/
typedef int (*cpu_stop_fn_t)(void *arg);
#ifdef CONFIG_SMP
struct cpu_stop_work {
struct list_head list; /* cpu_stopper->works */
cpu_stop_fn_t fn;
void *arg;
struct cpu_stop_done *done;
};
int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg);
void stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
struct cpu_stop_work *work_buf);
int stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg);
int try_stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg);
#else /* CONFIG_SMP */
#include <linux/workqueue.h>
struct cpu_stop_work {
struct work_struct work;
cpu_stop_fn_t fn;
void *arg;
};
static inline int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
{
int ret = -ENOENT;
preempt_disable();
if (cpu == smp_processor_id())
ret = fn(arg);
preempt_enable();
return ret;
}
static void stop_one_cpu_nowait_workfn(struct work_struct *work)
{
struct cpu_stop_work *stwork =
container_of(work, struct cpu_stop_work, work);
preempt_disable();
stwork->fn(stwork->arg);
preempt_enable();
}
static inline void stop_one_cpu_nowait(unsigned int cpu,
cpu_stop_fn_t fn, void *arg,
struct cpu_stop_work *work_buf)
{
if (cpu == smp_processor_id()) {
INIT_WORK(&work_buf->work, stop_one_cpu_nowait_workfn);
work_buf->fn = fn;
work_buf->arg = arg;
schedule_work(&work_buf->work);
}
}
static inline int stop_cpus(const struct cpumask *cpumask,
cpu_stop_fn_t fn, void *arg)
{
if (cpumask_test_cpu(raw_smp_processor_id(), cpumask))
return stop_one_cpu(raw_smp_processor_id(), fn, arg);
return -ENOENT;
}
static inline int try_stop_cpus(const struct cpumask *cpumask,
cpu_stop_fn_t fn, void *arg)
{
return stop_cpus(cpumask, fn, arg);
}
#endif /* CONFIG_SMP */
/*
* stop_machine "Bogolock": stop the entire machine, disable
* interrupts. This is a very heavy lock, which is equivalent to
* grabbing every spinlock (and more). So the "read" side to such a
* lock is anything which disables preemption.
*/
#if defined(CONFIG_STOP_MACHINE) && defined(CONFIG_SMP)
/**
* stop_machine: freeze the machine on all CPUs and run this function
* @fn: the function to run
* @data: the data ptr for the @fn()
* @cpus: the cpus to run the @fn() on (NULL = any online cpu)
*
* Description: This causes a thread to be scheduled on every cpu,
* each of which disables interrupts. The result is that no one is
* holding a spinlock or inside any other preempt-disabled region when
* @fn() runs.
*
* This can be thought of as a very heavy write lock, equivalent to
* grabbing every spinlock in the kernel. */
int stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus);
/**
* __stop_machine: freeze the machine on all CPUs and run this function
* @fn: the function to run
* @data: the data ptr for the @fn
* @cpus: the cpus to run the @fn() on (NULL = any online cpu)
*
* Description: This is a special version of the above, which assumes cpus
* won't come or go while it's being called. Used by hotplug cpu.
*/
int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus);
int stop_machine_from_inactive_cpu(int (*fn)(void *), void *data,
const struct cpumask *cpus);
#else /* CONFIG_STOP_MACHINE && CONFIG_SMP */
static inline int __stop_machine(int (*fn)(void *), void *data,
const struct cpumask *cpus)
{
unsigned long flags;
int ret;
local_irq_save(flags);
ret = fn(data);
local_irq_restore(flags);
return ret;
}
static inline int stop_machine(int (*fn)(void *), void *data,
const struct cpumask *cpus)
{
return __stop_machine(fn, data, cpus);
}
static inline int stop_machine_from_inactive_cpu(int (*fn)(void *), void *data,
const struct cpumask *cpus)
{
return __stop_machine(fn, data, cpus);
}
#endif /* CONFIG_STOP_MACHINE && CONFIG_SMP */
#endif /* _LINUX_STOP_MACHINE */