mirror of
https://github.com/torvalds/linux.git
synced 2024-11-11 22:51:42 +00:00
e32640a2cd
This patch creates smpcommon.c with functions that are equal between architectures. The i386-only init_gdt is ifdef'd. Note that smpcommon.o figures twice in the Makefile: this is because sub-architectures like voyager that does not use the normal smp_$(BITS) files also have to access them Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
84 lines
2.4 KiB
C
84 lines
2.4 KiB
C
/*
|
|
* SMP stuff which is common to all sub-architectures.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <asm/smp.h>
|
|
|
|
#ifdef CONFIG_X86_32
|
|
DEFINE_PER_CPU(unsigned long, this_cpu_off);
|
|
EXPORT_PER_CPU_SYMBOL(this_cpu_off);
|
|
|
|
/* Initialize the CPU's GDT. This is either the boot CPU doing itself
|
|
(still using the master per-cpu area), or a CPU doing it for a
|
|
secondary which will soon come up. */
|
|
__cpuinit void init_gdt(int cpu)
|
|
{
|
|
struct desc_struct *gdt = get_cpu_gdt_table(cpu);
|
|
|
|
pack_descriptor(&gdt[GDT_ENTRY_PERCPU],
|
|
__per_cpu_offset[cpu], 0xFFFFF,
|
|
0x2 | DESCTYPE_S, 0x8);
|
|
|
|
gdt[GDT_ENTRY_PERCPU].s = 1;
|
|
|
|
per_cpu(this_cpu_off, cpu) = __per_cpu_offset[cpu];
|
|
per_cpu(cpu_number, cpu) = cpu;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* smp_call_function(): Run a function on all other CPUs.
|
|
* @func: The function to run. This must be fast and non-blocking.
|
|
* @info: An arbitrary pointer to pass to the function.
|
|
* @nonatomic: Unused.
|
|
* @wait: If true, wait (atomically) until function has completed on other CPUs.
|
|
*
|
|
* Returns 0 on success, else a negative status code.
|
|
*
|
|
* If @wait is true, then returns once @func has returned; otherwise
|
|
* it returns just before the target cpu calls @func.
|
|
*
|
|
* You must not call this function with disabled interrupts or from a
|
|
* hardware interrupt handler or from a bottom half handler.
|
|
*/
|
|
int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
|
|
int wait)
|
|
{
|
|
return smp_call_function_mask(cpu_online_map, func, info, wait);
|
|
}
|
|
EXPORT_SYMBOL(smp_call_function);
|
|
|
|
/**
|
|
* smp_call_function_single - Run a function on a specific CPU
|
|
* @cpu: The target CPU. Cannot be the calling CPU.
|
|
* @func: The function to run. This must be fast and non-blocking.
|
|
* @info: An arbitrary pointer to pass to the function.
|
|
* @nonatomic: Unused.
|
|
* @wait: If true, wait until function has completed on other CPUs.
|
|
*
|
|
* Returns 0 on success, else a negative status code.
|
|
*
|
|
* If @wait is true, then returns once @func has returned; otherwise
|
|
* it returns just before the target cpu calls @func.
|
|
*/
|
|
int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
|
|
int nonatomic, int wait)
|
|
{
|
|
/* prevent preemption and reschedule on another processor */
|
|
int ret;
|
|
int me = get_cpu();
|
|
if (cpu == me) {
|
|
local_irq_disable();
|
|
func(info);
|
|
local_irq_enable();
|
|
put_cpu();
|
|
return 0;
|
|
}
|
|
|
|
ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait);
|
|
|
|
put_cpu();
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(smp_call_function_single);
|