kernel-ark/include/linux/taskstats_kern.h
Oleg Nesterov b8534d7bd8 [PATCH] taskstats: kill ->taskstats_lock in favor of ->siglock
signal_struct is (mostly) protected by ->sighand->siglock, I think we don't
need ->taskstats_lock to protect ->stats.  This also allows us to simplify the
locking in fill_tgid().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 11:30:54 -07:00

81 lines
2.0 KiB
C

/* taskstats_kern.h - kernel header for per-task statistics interface
*
* Copyright (C) Shailabh Nagar, IBM Corp. 2006
* (C) Balbir Singh, IBM Corp. 2006
*/
#ifndef _LINUX_TASKSTATS_KERN_H
#define _LINUX_TASKSTATS_KERN_H
#include <linux/taskstats.h>
#include <linux/sched.h>
#include <net/genetlink.h>
#ifdef CONFIG_TASKSTATS
extern kmem_cache_t *taskstats_cache;
extern struct mutex taskstats_exit_mutex;
static inline void taskstats_exit_free(struct taskstats *tidstats)
{
if (tidstats)
kmem_cache_free(taskstats_cache, tidstats);
}
static inline void taskstats_tgid_init(struct signal_struct *sig)
{
sig->stats = NULL;
}
static inline void taskstats_tgid_alloc(struct task_struct *tsk)
{
struct signal_struct *sig = tsk->signal;
struct taskstats *stats;
if (sig->stats != NULL)
return;
/* No problem if kmem_cache_zalloc() fails */
stats = kmem_cache_zalloc(taskstats_cache, SLAB_KERNEL);
spin_lock_irq(&tsk->sighand->siglock);
if (!sig->stats) {
sig->stats = stats;
stats = NULL;
}
spin_unlock_irq(&tsk->sighand->siglock);
if (stats)
kmem_cache_free(taskstats_cache, stats);
}
static inline void taskstats_tgid_free(struct signal_struct *sig)
{
if (sig->stats)
kmem_cache_free(taskstats_cache, sig->stats);
}
extern void taskstats_exit_alloc(struct taskstats **, unsigned int *);
extern void taskstats_exit_send(struct task_struct *, struct taskstats *, int, unsigned int);
extern void taskstats_init_early(void);
#else
static inline void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu)
{}
static inline void taskstats_exit_free(struct taskstats *ptidstats)
{}
static inline void taskstats_exit_send(struct task_struct *tsk,
struct taskstats *tidstats,
int group_dead, unsigned int cpu)
{}
static inline void taskstats_tgid_init(struct signal_struct *sig)
{}
static inline void taskstats_tgid_alloc(struct task_struct *tsk)
{}
static inline void taskstats_tgid_free(struct signal_struct *sig)
{}
static inline void taskstats_init_early(void)
{}
#endif /* CONFIG_TASKSTATS */
#endif