Commit d00bcc98 authored by Christoph Lameter's avatar Christoph Lameter Committed by Linus Torvalds
Browse files

[PATCH] Extract the allocpercpu functions from the slab allocator 



The allocpercpu functions __alloc_percpu and __free_percpu() are heavily
using the slab allocator.  However, they are conceptually slab.  This also
simplifies SLOB (at this point slob may be broken in mm.  This should fix
it).

Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 39bbcb8f

mm/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -23,4 +23,4 @@ obj-$(CONFIG_SLAB) += slab.o 
obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o

obj-$(CONFIG_FS_XIP) += filemap_xip.o

obj-$(CONFIG_MIGRATION) += migrate.o

obj-$(CONFIG_SMP) += allocpercpu.o

mm/allocpercpu.c

0 → 100644
+129 −0
Original line number Diff line number Diff line 
/*

 * linux/mm/allocpercpu.c

 *

 * Separated from slab.c August 11, 2006 Christoph Lameter <clameter@sgi.com>

 */

#include <linux/mm.h>

#include <linux/module.h>



/**

 * 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);

	if (pdata->ptrs[cpu]) {

		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);



	BUG_ON(pdata->ptrs[cpu]);

	if (node_online(node)) {

		/* FIXME: kzalloc_node(size, gfp, node) */

		pdata->ptrs[cpu] = kmalloc_node(size, gfp, node);

		if (pdata->ptrs[cpu])

			memset(pdata->ptrs[cpu], 0, size);

	} 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 = CPU_MASK_NONE;

	int cpu;



	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)

{

	void *pdata = kzalloc(sizeof(struct percpu_data), 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)

{

	__percpu_depopulate_mask(__pdata, &cpu_possible_map);

	kfree(__percpu_disguise(__pdata));

}

EXPORT_SYMBOL_GPL(percpu_free);

mm/slab.c

+0 −124
Original line number Diff line number Diff line
@@ -3440,130 +3440,6 @@ void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) 
EXPORT_SYMBOL(__kmalloc_track_caller);

#endif



#ifdef CONFIG_SMP

/**

 * 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);

	if (pdata->ptrs[cpu]) {

		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);



	BUG_ON(pdata->ptrs[cpu]);

	if (node_online(node)) {

		/* FIXME: kzalloc_node(size, gfp, node) */

		pdata->ptrs[cpu] = kmalloc_node(size, gfp, node);

		if (pdata->ptrs[cpu])

			memset(pdata->ptrs[cpu], 0, size);

	} 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 = CPU_MASK_NONE;

	int cpu;



	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)

{

	void *pdata = kzalloc(sizeof(struct percpu_data), 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)

{

	__percpu_depopulate_mask(__pdata, &cpu_possible_map);

	kfree(__percpu_disguise(__pdata));

}

EXPORT_SYMBOL_GPL(percpu_free);

#endif	/* CONFIG_SMP */



/**

 * kmem_cache_free - Deallocate an object

 * @cachep: The cache the allocation was from.

mm/slob.c

+0 −45
Original line number Diff line number Diff line
@@ -343,48 +343,3 @@ void kmem_cache_init(void) 
atomic_t slab_reclaim_pages = ATOMIC_INIT(0);

EXPORT_SYMBOL(slab_reclaim_pages);

#ifdef CONFIG_SMP



void *__alloc_percpu(size_t size)

{

	int i;

	struct percpu_data *pdata = kmalloc(sizeof (*pdata), GFP_KERNEL);



	if (!pdata)

		return NULL;



	for_each_possible_cpu(i) {

		pdata->ptrs[i] = kmalloc(size, GFP_KERNEL);

		if (!pdata->ptrs[i])

			goto unwind_oom;

		memset(pdata->ptrs[i], 0, size);

	}



	/* Catch derefs w/o wrappers */

	return (void *) (~(unsigned long) pdata);



unwind_oom:

	while (--i >= 0) {

		if (!cpu_possible(i))

			continue;

		kfree(pdata->ptrs[i]);

	}

	kfree(pdata);

	return NULL;

}

EXPORT_SYMBOL(__alloc_percpu);



void

free_percpu(const void *objp)

{

	int i;

	struct percpu_data *p = (struct percpu_data *) (~(unsigned long) objp);



	for_each_possible_cpu(i)

		kfree(p->ptrs[i]);



	kfree(p);

}

EXPORT_SYMBOL(free_percpu);



#endif

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