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authorPeter Zijlstra <a.p.zijlstra@chello.nl>2009-02-05 12:24:16 +0100
committerIngo Molnar <mingo@elte.hu>2009-02-05 13:04:33 +0100
commit4cd4c1b40d40447fb5e7ba80746c6d7ba91d7a53 (patch)
treeb1e580d5284648d6884e951d995509094a92cca4 /kernel/itimer.c
parent32bd671d6cbeda60dc73be77fa2b9037d9a9bfa0 (diff)
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timers: split process wide cpu clocks/timers
Change the process wide cpu timers/clocks so that we: 1) don't mess up the kernel with too many threads, 2) don't have a per-cpu allocation for each process, 3) have no impact when not used. In order to accomplish this we're going to split it into two parts: - clocks; which can take all the time they want since they run from user context -- ie. sys_clock_gettime(CLOCK_PROCESS_CPUTIME_ID) - timers; which need constant time sampling but since they're explicity used, the user can pay the overhead. The clock readout will go back to a full sum of the thread group, while the timers will run of a global 'clock' that only runs when needed, so only programs that make use of the facility pay the price. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/itimer.c')
-rw-r--r--kernel/itimer.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/itimer.c b/kernel/itimer.c
index 6a5fe93dd8bd..58762f7077ec 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -62,7 +62,7 @@ int do_getitimer(int which, struct itimerval *value)
struct task_cputime cputime;
cputime_t utime;
- thread_group_cputime(tsk, &cputime);
+ thread_group_cputimer(tsk, &cputime);
utime = cputime.utime;
if (cputime_le(cval, utime)) { /* about to fire */
cval = jiffies_to_cputime(1);
@@ -82,7 +82,7 @@ int do_getitimer(int which, struct itimerval *value)
struct task_cputime times;
cputime_t ptime;
- thread_group_cputime(tsk, &times);
+ thread_group_cputimer(tsk, &times);
ptime = cputime_add(times.utime, times.stime);
if (cputime_le(cval, ptime)) { /* about to fire */
cval = jiffies_to_cputime(1);