From b663a79c191508f27cd885224b592a878c0ba0f6 Mon Sep 17 00:00:00 2001 From: Maxim Uvarov Date: Sun, 15 Jul 2007 23:40:48 -0700 Subject: taskstats: add context-switch counters Make available to the user the following task and process performance statistics: * Involuntary Context Switches (task_struct->nivcsw) * Voluntary Context Switches (task_struct->nvcsw) Statistics information is available from: 1. taskstats interface (Documentation/accounting/) 2. /proc/PID/status (task only). This data is useful for detecting hyperactivity patterns between processes. [akpm@linux-foundation.org: cleanup] Signed-off-by: Maxim Uvarov Cc: Shailabh Nagar Cc: Balbir Singh Cc: Jay Lan Cc: Jonathan Lim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/taskstats.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel/taskstats.c') diff --git a/kernel/taskstats.c b/kernel/taskstats.c index 906cae771585..059431ed67db 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -196,6 +196,8 @@ static int fill_pid(pid_t pid, struct task_struct *tsk, /* fill in basic acct fields */ stats->version = TASKSTATS_VERSION; + stats->nvcsw = tsk->nvcsw; + stats->nivcsw = tsk->nivcsw; bacct_add_tsk(stats, tsk); /* fill in extended acct fields */ @@ -242,6 +244,8 @@ static int fill_tgid(pid_t tgid, struct task_struct *first, */ delayacct_add_tsk(stats, tsk); + stats->nvcsw += tsk->nvcsw; + stats->nivcsw += tsk->nivcsw; } while_each_thread(first, tsk); unlock_task_sighand(first, &flags); -- cgit v1.2.3