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kref: Inline all functions

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These are tiny functions, there's no point in having them out-of-line.

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-8eccvi2ur2fzgi00xdjlbf5z@git.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Peter Zijlstra
2011-12-13 10:36:20 +01:00
committed by Greg Kroah-Hartman
parent 175cad2667
commit 4af679cd7c
3 changed files with 76 additions and 103 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
include/linux/kref.h
View File

@@ -16,15 +16,85 @@
#define _KREF_H_ #define _KREF_H_
#include <linux/types.h> #include <linux/types.h>
#include <linux/slab.h>
struct kref { struct kref {
atomic_t refcount; atomic_t refcount;
}; };
void kref_init(struct kref *kref); /**
void kref_get(struct kref *kref); * kref_init - initialize object.
int kref_put(struct kref *kref, void (*release) (struct kref *kref)); * @kref: object in question.
int kref_sub(struct kref *kref, unsigned int count, */
void (*release) (struct kref *kref)); static inline void kref_init(struct kref *kref)
{
atomic_set(&kref->refcount, 1);
smp_mb();
}
/**
* kref_get - increment refcount for object.
* @kref: object.
*/
static inline void kref_get(struct kref *kref)
{
WARN_ON(!atomic_read(&kref->refcount));
atomic_inc(&kref->refcount);
smp_mb__after_atomic_inc();
}
/**
* kref_put - decrement refcount for object.
* @kref: object.
* @release: pointer to the function that will clean up the object when the
* last reference to the object is released.
* This pointer is required, and it is not acceptable to pass kfree
* in as this function.
*
* Decrement the refcount, and if 0, call release().
* Return 1 if the object was removed, otherwise return 0. Beware, if this
* function returns 0, you still can not count on the kref from remaining in
* memory. Only use the return value if you want to see if the kref is now
* gone, not present.
*/
static inline int kref_put(struct kref *kref, void (*release)(struct kref *kref))
{
WARN_ON(release == NULL);
WARN_ON(release == (void (*)(struct kref *))kfree);
if (atomic_dec_and_test(&kref->refcount)) {
release(kref);
return 1;
}
return 0;
}
/**
* kref_sub - subtract a number of refcounts for object.
* @kref: object.
* @count: Number of recounts to subtract.
* @release: pointer to the function that will clean up the object when the
* last reference to the object is released.
* This pointer is required, and it is not acceptable to pass kfree
* in as this function.
*
* Subtract @count from the refcount, and if 0, call release().
* Return 1 if the object was removed, otherwise return 0. Beware, if this
* function returns 0, you still can not count on the kref from remaining in
* memory. Only use the return value if you want to see if the kref is now
* gone, not present.
*/
static inline int kref_sub(struct kref *kref, unsigned int count,
void (*release)(struct kref *kref))
{
WARN_ON(release == NULL);
WARN_ON(release == (void (*)(struct kref *))kfree);
if (atomic_sub_and_test((int) count, &kref->refcount)) {
release(kref);
return 1;
}
return 0;
}
#endif /* _KREF_H_ */ #endif /* _KREF_H_ */

2
lib/Makefile
View File

@@ -17,7 +17,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o kref.o klist.o lib-y += kobject.o klist.o
obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \

97
lib/kref.c
View File

@@ -1,97 +0,0 @@
/*
* kref.c - library routines for handling generic reference counted objects
*
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2004 IBM Corp.
*
* based on lib/kobject.c which was:
* Copyright (C) 2002-2003 Patrick Mochel <mochel@osdl.org>
*
* This file is released under the GPLv2.
*
*/
#include <linux/kref.h>
#include <linux/module.h>
#include <linux/slab.h>
/**
* kref_init - initialize object.
* @kref: object in question.
*/
void kref_init(struct kref *kref)
{
atomic_set(&kref->refcount, 1);
smp_mb();
}
/**
* kref_get - increment refcount for object.
* @kref: object.
*/
void kref_get(struct kref *kref)
{
WARN_ON(!atomic_read(&kref->refcount));
atomic_inc(&kref->refcount);
smp_mb__after_atomic_inc();
}
/**
* kref_put - decrement refcount for object.
* @kref: object.
* @release: pointer to the function that will clean up the object when the
* last reference to the object is released.
* This pointer is required, and it is not acceptable to pass kfree
* in as this function.
*
* Decrement the refcount, and if 0, call release().
* Return 1 if the object was removed, otherwise return 0. Beware, if this
* function returns 0, you still can not count on the kref from remaining in
* memory. Only use the return value if you want to see if the kref is now
* gone, not present.
*/
int kref_put(struct kref *kref, void (*release)(struct kref *kref))
{
WARN_ON(release == NULL);
WARN_ON(release == (void (*)(struct kref *))kfree);
if (atomic_dec_and_test(&kref->refcount)) {
release(kref);
return 1;
}
return 0;
}
/**
* kref_sub - subtract a number of refcounts for object.
* @kref: object.
* @count: Number of recounts to subtract.
* @release: pointer to the function that will clean up the object when the
* last reference to the object is released.
* This pointer is required, and it is not acceptable to pass kfree
* in as this function.
*
* Subtract @count from the refcount, and if 0, call release().
* Return 1 if the object was removed, otherwise return 0. Beware, if this
* function returns 0, you still can not count on the kref from remaining in
* memory. Only use the return value if you want to see if the kref is now
* gone, not present.
*/
int kref_sub(struct kref *kref, unsigned int count,
void (*release)(struct kref *kref))
{
WARN_ON(release == NULL);
WARN_ON(release == (void (*)(struct kref *))kfree);
if (atomic_sub_and_test((int) count, &kref->refcount)) {
release(kref);
return 1;
}
return 0;
}
EXPORT_SYMBOL(kref_init);
EXPORT_SYMBOL(kref_get);
EXPORT_SYMBOL(kref_put);
EXPORT_SYMBOL(kref_sub);