b8534d7bd8
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>
81 lines
2 KiB
C
81 lines
2 KiB
C
/* taskstats_kern.h - kernel header for per-task statistics interface
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*
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* Copyright (C) Shailabh Nagar, IBM Corp. 2006
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* (C) Balbir Singh, IBM Corp. 2006
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*/
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#ifndef _LINUX_TASKSTATS_KERN_H
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#define _LINUX_TASKSTATS_KERN_H
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#include <linux/taskstats.h>
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#include <linux/sched.h>
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#include <net/genetlink.h>
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#ifdef CONFIG_TASKSTATS
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extern kmem_cache_t *taskstats_cache;
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extern struct mutex taskstats_exit_mutex;
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static inline void taskstats_exit_free(struct taskstats *tidstats)
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{
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if (tidstats)
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kmem_cache_free(taskstats_cache, tidstats);
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}
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static inline void taskstats_tgid_init(struct signal_struct *sig)
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{
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sig->stats = NULL;
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}
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static inline void taskstats_tgid_alloc(struct task_struct *tsk)
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{
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struct signal_struct *sig = tsk->signal;
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struct taskstats *stats;
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if (sig->stats != NULL)
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return;
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/* No problem if kmem_cache_zalloc() fails */
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stats = kmem_cache_zalloc(taskstats_cache, SLAB_KERNEL);
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spin_lock_irq(&tsk->sighand->siglock);
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if (!sig->stats) {
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sig->stats = stats;
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stats = NULL;
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}
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spin_unlock_irq(&tsk->sighand->siglock);
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if (stats)
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kmem_cache_free(taskstats_cache, stats);
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}
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static inline void taskstats_tgid_free(struct signal_struct *sig)
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{
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if (sig->stats)
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kmem_cache_free(taskstats_cache, sig->stats);
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}
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extern void taskstats_exit_alloc(struct taskstats **, unsigned int *);
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extern void taskstats_exit_send(struct task_struct *, struct taskstats *, int, unsigned int);
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extern void taskstats_init_early(void);
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#else
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static inline void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu)
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{}
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static inline void taskstats_exit_free(struct taskstats *ptidstats)
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{}
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static inline void taskstats_exit_send(struct task_struct *tsk,
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struct taskstats *tidstats,
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int group_dead, unsigned int cpu)
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{}
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static inline void taskstats_tgid_init(struct signal_struct *sig)
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{}
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static inline void taskstats_tgid_alloc(struct task_struct *tsk)
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{}
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static inline void taskstats_tgid_free(struct signal_struct *sig)
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{}
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static inline void taskstats_init_early(void)
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{}
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#endif /* CONFIG_TASKSTATS */
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#endif
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