Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030294AbWEDSr5 (ORCPT ); Thu, 4 May 2006 14:47:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030295AbWEDSr5 (ORCPT ); Thu, 4 May 2006 14:47:57 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:41707 "EHLO e34.co.us.ibm.com") by vger.kernel.org with ESMTP id S1030294AbWEDSr4 (ORCPT ); Thu, 4 May 2006 14:47:56 -0400 Date: Fri, 5 May 2006 00:14:42 +0530 From: Balbir Singh To: linux-kernel@vger.kernel.org Cc: lse-tech@lists.sourceforge.net, jlan@engr.sgi.com, akpm@osdl.org Subject: [updated] [Patch 6/8] delay accounting usage of taskstats interface Message-ID: <20060504184442.GC6966@in.ibm.com> Reply-To: balbir@in.ibm.com References: <20060502061930.GC22607@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060502061930.GC22607@in.ibm.com> User-Agent: Mutt/1.5.10i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7692 Lines: 233 Changelog Fixes suggested by Jay Lan - check for tidstats before taking the mutex_lock in taskstats_exit_send() - add back and fill version information for struct taskstats Fixes comments by akpm (on earlier patch now incorporated here) - detailed comments on atomicity rules of accounting fields - replace use of nsec_t delayacct-taskstats.patch Usage of taskstats interface by delay accounting. Signed-off-by: Shailabh Nagar Signed-off-by: Balbir Singh --- include/linux/delayacct.h | 13 ++++++++++++ include/linux/taskstats.h | 49 ++++++++++++++++++++++++++++++++++++++++++++++ init/Kconfig | 1 kernel/delayacct.c | 42 +++++++++++++++++++++++++++++++++++++++ kernel/taskstats.c | 12 ++++++++++- 5 files changed, 116 insertions(+), 1 deletion(-) diff -puN include/linux/delayacct.h~delayacct-taskstats include/linux/delayacct.h --- linux-2.6.17-rc3/include/linux/delayacct.h~delayacct-taskstats 2006-05-04 09:31:59.000000000 +0530 +++ linux-2.6.17-rc3-balbir/include/linux/delayacct.h 2006-05-04 11:26:18.000000000 +0530 @@ -18,6 +18,7 @@ #define _LINUX_DELAYACCT_H #include +#include /* * Per-task flags relevant to delay accounting @@ -35,6 +36,7 @@ extern void __delayacct_tsk_init(struct extern void __delayacct_tsk_exit(struct task_struct *); extern void __delayacct_blkio_start(void); extern void __delayacct_blkio_end(void); +extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); static inline void delayacct_set_flag(int flag) { @@ -74,6 +76,14 @@ static inline void delayacct_blkio_end(v __delayacct_blkio_end(); } +static inline int delayacct_add_tsk(struct taskstats *d, + struct task_struct *tsk) +{ + if (!tsk->delays) + return -EINVAL; + return __delayacct_add_tsk(d, tsk); +} + #else static inline void delayacct_set_flag(int flag) {} @@ -89,6 +99,9 @@ static inline void delayacct_blkio_start {} static inline void delayacct_blkio_end(void) {} +static inline int delayacct_add_tsk(struct taskstats *d, + struct task_struct *tsk) +{ return 0; } #endif /* CONFIG_TASK_DELAY_ACCT */ #endif diff -puN include/linux/taskstats.h~delayacct-taskstats include/linux/taskstats.h --- linux-2.6.17-rc3/include/linux/taskstats.h~delayacct-taskstats 2006-05-04 09:31:59.000000000 +0530 +++ linux-2.6.17-rc3-balbir/include/linux/taskstats.h 2006-05-04 09:34:11.000000000 +0530 @@ -35,6 +35,55 @@ struct taskstats { /* Version 1 */ __u64 version; + + /* Delay accounting fields start + * + * All values, until comment "Delay accounting fields end" are + * available only if delay accounting is enabled, even though the last + * few fields are not delays + * + * xxx_count is the number of delay values recorded + * xxx_delay_total is the corresponding cumulative delay in nanoseconds + * + * xxx_delay_total wraps around to zero on overflow + * xxx_count incremented regardless of overflow + */ + + /* Delay waiting for cpu, while runnable + * count, delay_total NOT updated atomically + */ + __u64 cpu_count; + __u64 cpu_delay_total; + + /* Following four fields atomically updated using task->delays->lock */ + + /* Delay waiting for synchronous block I/O to complete + * does not account for delays in I/O submission + */ + __u64 blkio_count; + __u64 blkio_delay_total; + + /* Delay waiting for page fault I/O (swap in only) */ + __u64 swapin_count; + __u64 swapin_delay_total; + + /* cpu "wall-clock" running time + * On some architectures, value will adjust for cpu time stolen + * from the kernel in involuntary waits due to virtualization. + * Value is cumulative, in nanoseconds, without a corresponding count + * and wraps around to zero silently on overflow + */ + __u64 cpu_run_real_total; + + /* cpu "virtual" running time + * Uses time intervals seen by the kernel i.e. no adjustment + * for kernel's involuntary waits due to virtualization. + * Value is cumulative, in nanoseconds, without a corresponding count + * and wraps around to zero silently on overflow + */ + __u64 cpu_run_virtual_total; + /* Delay accounting fields end */ + /* version 1 ends here */ }; diff -puN init/Kconfig~delayacct-taskstats init/Kconfig --- linux-2.6.17-rc3/init/Kconfig~delayacct-taskstats 2006-05-04 09:31:59.000000000 +0530 +++ linux-2.6.17-rc3-balbir/init/Kconfig 2006-05-04 09:31:59.000000000 +0530 @@ -164,6 +164,7 @@ config TASKSTATS config TASK_DELAY_ACCT bool "Enable per-task delay accounting (EXPERIMENTAL)" + depends on TASKSTATS help Collect information on time spent by a task waiting for system resources like cpu, synchronous block I/O completion and swapping diff -puN kernel/delayacct.c~delayacct-taskstats kernel/delayacct.c --- linux-2.6.17-rc3/kernel/delayacct.c~delayacct-taskstats 2006-05-04 09:31:59.000000000 +0530 +++ linux-2.6.17-rc3-balbir/kernel/delayacct.c 2006-05-04 11:26:18.000000000 +0530 @@ -104,3 +104,45 @@ void __delayacct_blkio_end(void) ¤t->delays->blkio_delay, ¤t->delays->blkio_count); } + +int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) +{ + s64 tmp; + struct timespec ts; + unsigned long t1,t2,t3; + + tmp = (s64)d->cpu_run_real_total; + tmp += (u64)(tsk->utime + tsk->stime) * TICK_NSEC; + d->cpu_run_real_total = (tmp < (s64)d->cpu_run_real_total) ? 0 : tmp; + + /* + * No locking available for sched_info (and too expensive to add one) + * Mitigate by taking snapshot of values + */ + t1 = tsk->sched_info.pcnt; + t2 = tsk->sched_info.run_delay; + t3 = tsk->sched_info.cpu_time; + + d->cpu_count += t1; + + jiffies_to_timespec(t2, &ts); + tmp = (s64)d->cpu_delay_total + timespec_to_ns(&ts); + d->cpu_delay_total = (tmp < (s64)d->cpu_delay_total) ? 0 : tmp; + + tmp = (s64)d->cpu_run_virtual_total + (s64)jiffies_to_usecs(t3) * 1000; + d->cpu_run_virtual_total = + (tmp < (s64)d->cpu_run_virtual_total) ? 0 : tmp; + + /* zero XXX_total, non-zero XXX_count implies XXX stat overflowed */ + + spin_lock(&tsk->delays->lock); + tmp = d->blkio_delay_total + tsk->delays->blkio_delay; + d->blkio_delay_total = (tmp < d->blkio_delay_total) ? 0 : tmp; + tmp = d->swapin_delay_total + tsk->delays->swapin_delay; + d->swapin_delay_total = (tmp < d->swapin_delay_total) ? 0 : tmp; + d->blkio_count += tsk->delays->blkio_count; + d->swapin_count += tsk->delays->swapin_count; + spin_unlock(&tsk->delays->lock); + + return 0; +} diff -puN kernel/taskstats.c~delayacct-taskstats kernel/taskstats.c --- linux-2.6.17-rc3/kernel/taskstats.c~delayacct-taskstats 2006-05-04 09:31:59.000000000 +0530 +++ linux-2.6.17-rc3-balbir/kernel/taskstats.c 2006-05-04 11:27:53.000000000 +0530 @@ -18,6 +18,7 @@ #include #include +#include #include #include @@ -120,7 +121,10 @@ static int fill_pid(pid_t pid, struct ta * goto err; */ -err: + rc = delayacct_add_tsk(stats, tsk); + stats->version = TASKSTATS_VERSION; + + /* Define err: label here if needed */ put_task_struct(tsk); return rc; @@ -152,8 +156,14 @@ static int fill_tgid(pid_t tgid, struct * break; */ + rc = delayacct_add_tsk(stats, tsk); + if (rc) + break; + } while_each_thread(first, tsk); read_unlock(&tasklist_lock); + stats->version = TASKSTATS_VERSION; + /* * Accounting subsytems can also add calls here if they don't _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/