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smp: Consolidate the various smp_call_function_single() declensions

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__smp_call_function_single() and smp_call_function_single() share some
code that can be factorized: execute inline when the target is local,
check if the target is online, lock the csd, call generic_exec_single().

Lets move the common parts to generic_exec_single().

Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Frederic Weisbecker 2014-02-24 16:39:58 +01:00 committed by Jens Axboe
parent 08eed44c72
commit 8b28499a71
1 changed files with 39 additions and 41 deletions
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80
kernel/smp.c
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@ -117,13 +117,43 @@ static void csd_unlock(struct call_single_data *csd)
csd->flags &= ~CSD_FLAG_LOCK;
}
static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
/*
* Insert a previously allocated call_single_data element
* for execution on the given CPU. data must already have
* ->func, ->info, and ->flags set.
*/
static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
static int generic_exec_single(int cpu, struct call_single_data *csd,
smp_call_func_t func, void *info, int wait)
{
struct call_single_data csd_stack = { .flags = 0 };
unsigned long flags;
if (cpu == smp_processor_id()) {
local_irq_save(flags);
func(info);
local_irq_restore(flags);
return 0;
}
if ((unsigned)cpu >= nr_cpu_ids || !cpu_online(cpu))
return -ENXIO;
if (!csd) {
csd = &csd_stack;
if (!wait)
csd = &__get_cpu_var(csd_data);
}
csd_lock(csd);
csd->func = func;
csd->info = info;
if (wait)
csd->flags |= CSD_FLAG_WAIT;
@ -143,6 +173,8 @@ static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
if (wait)
csd_lock_wait(csd);
return 0;
}
/*
@ -168,8 +200,6 @@ void generic_smp_call_function_single_interrupt(void)
}
}
static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
/*
* smp_call_function_single - Run a function on a specific CPU
* @func: The function to run. This must be fast and non-blocking.
@ -181,12 +211,8 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
int wait)
{
struct call_single_data d = {
.flags = 0,
};
unsigned long flags;
int this_cpu;
int err = 0;
int err;
/*
* prevent preemption and reschedule on another processor,
@ -203,26 +229,7 @@ int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
&& !oops_in_progress);
if (cpu == this_cpu) {
local_irq_save(flags);
func(info);
local_irq_restore(flags);
} else {
if ((unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) {
struct call_single_data *csd = &d;
if (!wait)
csd = &__get_cpu_var(csd_data);
csd_lock(csd);
csd->func = func;
csd->info = info;
generic_exec_single(cpu, csd, wait);
} else {
err = -ENXIO; /* CPU not online */
}
}
err = generic_exec_single(cpu, NULL, func, info, wait);
put_cpu();
@ -285,9 +292,8 @@ EXPORT_SYMBOL_GPL(smp_call_function_any);
*/
int __smp_call_function_single(int cpu, struct call_single_data *csd, int wait)
{
unsigned int this_cpu;
unsigned long flags;
int err = 0;
int this_cpu;
this_cpu = get_cpu();
/*
@ -296,20 +302,12 @@ int __smp_call_function_single(int cpu, struct call_single_data *csd, int wait)
* send smp call function interrupt to this cpu and as such deadlocks
* can't happen.
*/
WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled()
WARN_ON_ONCE(cpu_online(this_cpu) && wait && irqs_disabled()
&& !oops_in_progress);
if (cpu == this_cpu) {
local_irq_save(flags);
csd->func(csd->info);
local_irq_restore(flags);
} else if ((unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) {
csd_lock(csd);
generic_exec_single(cpu, csd, wait);
} else {
err = -ENXIO; /* CPU not online */
}
err = generic_exec_single(cpu, csd, csd->func, csd->info, wait);
put_cpu();
return err;
}
EXPORT_SYMBOL_GPL(__smp_call_function_single);