diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | kernel/delayacct.c | 87 | ||||
| -rw-r--r-- | kernel/exit.c | 2 | ||||
| -rw-r--r-- | kernel/fork.c | 2 |
4 files changed, 92 insertions, 0 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 47dbcd570cd8d..87bb34cc89382 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ obj-$(CONFIG_SECCOMP) += seccomp.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o obj-$(CONFIG_RELAY) += relay.o +obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is diff --git a/kernel/delayacct.c b/kernel/delayacct.c new file mode 100644 index 0000000000000..fbf7f22849528 --- /dev/null +++ b/kernel/delayacct.c @@ -0,0 +1,87 @@ +/* delayacct.c - per-task delay accounting + * + * Copyright (C) Shailabh Nagar, IBM Corp. 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/sysctl.h> +#include <linux/delayacct.h> + +int delayacct_on __read_mostly; /* Delay accounting turned on/off */ +kmem_cache_t *delayacct_cache; + +static int __init delayacct_setup_enable(char *str) +{ + delayacct_on = 1; + return 1; +} +__setup("delayacct", delayacct_setup_enable); + +void delayacct_init(void) +{ + delayacct_cache = kmem_cache_create("delayacct_cache", + sizeof(struct task_delay_info), + 0, + SLAB_PANIC, + NULL, NULL); + delayacct_tsk_init(&init_task); +} + +void __delayacct_tsk_init(struct task_struct *tsk) +{ + tsk->delays = kmem_cache_zalloc(delayacct_cache, SLAB_KERNEL); + if (tsk->delays) + spin_lock_init(&tsk->delays->lock); +} + +void __delayacct_tsk_exit(struct task_struct *tsk) +{ + kmem_cache_free(delayacct_cache, tsk->delays); + tsk->delays = NULL; +} + +/* + * Start accounting for a delay statistic using + * its starting timestamp (@start) + */ + +static inline void delayacct_start(struct timespec *start) +{ + do_posix_clock_monotonic_gettime(start); +} + +/* + * Finish delay accounting for a statistic using + * its timestamps (@start, @end), accumalator (@total) and @count + */ + +static void delayacct_end(struct timespec *start, struct timespec *end, + u64 *total, u32 *count) +{ + struct timespec ts; + s64 ns; + + do_posix_clock_monotonic_gettime(end); + ts = timespec_sub(*end, *start); + ns = timespec_to_ns(&ts); + if (ns < 0) + return; + + spin_lock(¤t->delays->lock); + *total += ns; + (*count)++; + spin_unlock(¤t->delays->lock); +} + diff --git a/kernel/exit.c b/kernel/exit.c index 6664c084783d4..3c2cf91defa76 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -25,6 +25,7 @@ #include <linux/mount.h> #include <linux/proc_fs.h> #include <linux/mempolicy.h> +#include <linux/delayacct.h> #include <linux/cpuset.h> #include <linux/syscalls.h> #include <linux/signal.h> @@ -900,6 +901,7 @@ fastcall NORET_TYPE void do_exit(long code) #endif if (unlikely(tsk->audit_context)) audit_free(tsk); + delayacct_tsk_exit(tsk); exit_mm(tsk); if (group_dead) diff --git a/kernel/fork.c b/kernel/fork.c index 926e5a68ea9e7..451cfd35bf22c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -43,6 +43,7 @@ #include <linux/rmap.h> #include <linux/acct.h> #include <linux/cn_proc.h> +#include <linux/delayacct.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -1000,6 +1001,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, goto bad_fork_cleanup_put_domain; p->did_exec = 0; + delayacct_tsk_init(p); /* Must remain after dup_task_struct() */ copy_flags(clone_flags, p); p->pid = pid; retval = -EFAULT; |