mirror of
https://github.com/torvalds/linux.git
synced 2024-11-08 21:21:47 +00:00
d366f8cbc1
* Replace usages of CPU_MASK_NONE, CPU_MASK_ALL, NODE_MASK_NONE,
NODE_MASK_ALL to reduce stack requirements for large NR_CPUS
and MAXNODES counts.
* In some cases, the cpumask variable was initialized but then overwritten
with another value. This is the case for changes like this:
- cpumask_t oldmask = CPU_MASK_ALL;
+ cpumask_t oldmask;
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
142 lines
3.9 KiB
C
142 lines
3.9 KiB
C
/*
|
|
* linux/mm/allocpercpu.c
|
|
*
|
|
* Separated from slab.c August 11, 2006 Christoph Lameter <clameter@sgi.com>
|
|
*/
|
|
#include <linux/mm.h>
|
|
#include <linux/module.h>
|
|
|
|
#ifndef cache_line_size
|
|
#define cache_line_size() L1_CACHE_BYTES
|
|
#endif
|
|
|
|
/**
|
|
* percpu_depopulate - depopulate per-cpu data for given cpu
|
|
* @__pdata: per-cpu data to depopulate
|
|
* @cpu: depopulate per-cpu data for this cpu
|
|
*
|
|
* Depopulating per-cpu data for a cpu going offline would be a typical
|
|
* use case. You need to register a cpu hotplug handler for that purpose.
|
|
*/
|
|
void percpu_depopulate(void *__pdata, int cpu)
|
|
{
|
|
struct percpu_data *pdata = __percpu_disguise(__pdata);
|
|
|
|
kfree(pdata->ptrs[cpu]);
|
|
pdata->ptrs[cpu] = NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(percpu_depopulate);
|
|
|
|
/**
|
|
* percpu_depopulate_mask - depopulate per-cpu data for some cpu's
|
|
* @__pdata: per-cpu data to depopulate
|
|
* @mask: depopulate per-cpu data for cpu's selected through mask bits
|
|
*/
|
|
void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask)
|
|
{
|
|
int cpu;
|
|
for_each_cpu_mask(cpu, *mask)
|
|
percpu_depopulate(__pdata, cpu);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__percpu_depopulate_mask);
|
|
|
|
/**
|
|
* percpu_populate - populate per-cpu data for given cpu
|
|
* @__pdata: per-cpu data to populate further
|
|
* @size: size of per-cpu object
|
|
* @gfp: may sleep or not etc.
|
|
* @cpu: populate per-data for this cpu
|
|
*
|
|
* Populating per-cpu data for a cpu coming online would be a typical
|
|
* use case. You need to register a cpu hotplug handler for that purpose.
|
|
* Per-cpu object is populated with zeroed buffer.
|
|
*/
|
|
void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu)
|
|
{
|
|
struct percpu_data *pdata = __percpu_disguise(__pdata);
|
|
int node = cpu_to_node(cpu);
|
|
|
|
/*
|
|
* We should make sure each CPU gets private memory.
|
|
*/
|
|
size = roundup(size, cache_line_size());
|
|
|
|
BUG_ON(pdata->ptrs[cpu]);
|
|
if (node_online(node))
|
|
pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node);
|
|
else
|
|
pdata->ptrs[cpu] = kzalloc(size, gfp);
|
|
return pdata->ptrs[cpu];
|
|
}
|
|
EXPORT_SYMBOL_GPL(percpu_populate);
|
|
|
|
/**
|
|
* percpu_populate_mask - populate per-cpu data for more cpu's
|
|
* @__pdata: per-cpu data to populate further
|
|
* @size: size of per-cpu object
|
|
* @gfp: may sleep or not etc.
|
|
* @mask: populate per-cpu data for cpu's selected through mask bits
|
|
*
|
|
* Per-cpu objects are populated with zeroed buffers.
|
|
*/
|
|
int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp,
|
|
cpumask_t *mask)
|
|
{
|
|
cpumask_t populated;
|
|
int cpu;
|
|
|
|
cpus_clear(populated);
|
|
for_each_cpu_mask(cpu, *mask)
|
|
if (unlikely(!percpu_populate(__pdata, size, gfp, cpu))) {
|
|
__percpu_depopulate_mask(__pdata, &populated);
|
|
return -ENOMEM;
|
|
} else
|
|
cpu_set(cpu, populated);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__percpu_populate_mask);
|
|
|
|
/**
|
|
* percpu_alloc_mask - initial setup of per-cpu data
|
|
* @size: size of per-cpu object
|
|
* @gfp: may sleep or not etc.
|
|
* @mask: populate per-data for cpu's selected through mask bits
|
|
*
|
|
* Populating per-cpu data for all online cpu's would be a typical use case,
|
|
* which is simplified by the percpu_alloc() wrapper.
|
|
* Per-cpu objects are populated with zeroed buffers.
|
|
*/
|
|
void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
|
|
{
|
|
/*
|
|
* We allocate whole cache lines to avoid false sharing
|
|
*/
|
|
size_t sz = roundup(nr_cpu_ids * sizeof(void *), cache_line_size());
|
|
void *pdata = kzalloc(sz, gfp);
|
|
void *__pdata = __percpu_disguise(pdata);
|
|
|
|
if (unlikely(!pdata))
|
|
return NULL;
|
|
if (likely(!__percpu_populate_mask(__pdata, size, gfp, mask)))
|
|
return __pdata;
|
|
kfree(pdata);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__percpu_alloc_mask);
|
|
|
|
/**
|
|
* percpu_free - final cleanup of per-cpu data
|
|
* @__pdata: object to clean up
|
|
*
|
|
* We simply clean up any per-cpu object left. No need for the client to
|
|
* track and specify through a bis mask which per-cpu objects are to free.
|
|
*/
|
|
void percpu_free(void *__pdata)
|
|
{
|
|
if (unlikely(!__pdata))
|
|
return;
|
|
__percpu_depopulate_mask(__pdata, &cpu_possible_map);
|
|
kfree(__percpu_disguise(__pdata));
|
|
}
|
|
EXPORT_SYMBOL_GPL(percpu_free);
|