signals: make siginfo_t si_utime + si_sstime report times in USER_HZ, not HZ
authorMichael Kerrisk <mtk.manpages@googlemail.com>
Fri, 25 Jul 2008 08:47:32 +0000 (01:47 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 25 Jul 2008 17:53:39 +0000 (10:53 -0700)
In the switch to configurable HZ in 2.6, the treatment of the si_utime and
si_stime fields that are exposed to userland via the siginfo structure
looks to have been botched.  As things stand, these fields report times in
units of HZ, so that userland gets information that varies depending on
the HZ that the kernel was configured with.  This patch changes the
reported values to use USER_HZ units.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/signal.c

index 0514da5..ba60eee 100644 (file)
@@ -1370,10 +1370,9 @@ void do_notify_parent(struct task_struct *tsk, int sig)
 
        info.si_uid = tsk->uid;
 
-       /* FIXME: find out whether or not this is supposed to be c*time. */
-       info.si_utime = cputime_to_jiffies(cputime_add(tsk->utime,
+       info.si_utime = cputime_to_clock_t(cputime_add(tsk->utime,
                                                       tsk->signal->utime));
-       info.si_stime = cputime_to_jiffies(cputime_add(tsk->stime,
+       info.si_stime = cputime_to_clock_t(cputime_add(tsk->stime,
                                                       tsk->signal->stime));
 
        info.si_status = tsk->exit_code & 0x7f;
@@ -1441,9 +1440,8 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 
        info.si_uid = tsk->uid;
 
-       /* FIXME: find out whether or not this is supposed to be c*time. */
-       info.si_utime = cputime_to_jiffies(tsk->utime);
-       info.si_stime = cputime_to_jiffies(tsk->stime);
+       info.si_utime = cputime_to_clock_t(tsk->utime);
+       info.si_stime = cputime_to_clock_t(tsk->stime);
 
        info.si_code = why;
        switch (why) {