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| author | Heiko Carstens <hca@linux.ibm.com> | 2026-02-18 17:20:10 +0300 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2026-02-25 18:46:07 +0300 |
| commit | e282ccd308de7b2a65eb4596da8030c18b543071 (patch) | |
| tree | 5f92868b7a6c3cc340eae12bb1642c7f4be8a761 | |
| parent | d8b5cf9c63143fae54a734c41e3bb55cf3f365c7 (diff) | |
| download | linux-e282ccd308de7b2a65eb4596da8030c18b543071.tar.xz | |
s390/vtime: Use __this_cpu_read() / get rid of READ_ONCE()
do_account_vtime() runs always with interrupts disabled, therefore use
__this_cpu_read() instead of this_cpu_read() to get rid of a pointless
preempt_disable() / preempt_enable() pair.
Also there are no concurrent writers to the cpu time accounting fields
in lowcore. Therefore get rid of READ_ONCE() usages.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| -rw-r--r-- | arch/s390/kernel/vtime.c | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c index 122d30b10440..4111ff4d727c 100644 --- a/arch/s390/kernel/vtime.c +++ b/arch/s390/kernel/vtime.c @@ -137,23 +137,16 @@ static int do_account_vtime(struct task_struct *tsk) lc->system_timer += timer; /* Update MT utilization calculation */ - if (smp_cpu_mtid && - time_after64(jiffies_64, this_cpu_read(mt_scaling_jiffies))) + if (smp_cpu_mtid && time_after64(jiffies_64, __this_cpu_read(mt_scaling_jiffies))) update_mt_scaling(); /* Calculate cputime delta */ - user = update_tsk_timer(&tsk->thread.user_timer, - READ_ONCE(lc->user_timer)); - guest = update_tsk_timer(&tsk->thread.guest_timer, - READ_ONCE(lc->guest_timer)); - system = update_tsk_timer(&tsk->thread.system_timer, - READ_ONCE(lc->system_timer)); - hardirq = update_tsk_timer(&tsk->thread.hardirq_timer, - READ_ONCE(lc->hardirq_timer)); - softirq = update_tsk_timer(&tsk->thread.softirq_timer, - READ_ONCE(lc->softirq_timer)); - lc->steal_timer += - clock - user - guest - system - hardirq - softirq; + user = update_tsk_timer(&tsk->thread.user_timer, lc->user_timer); + guest = update_tsk_timer(&tsk->thread.guest_timer, lc->guest_timer); + system = update_tsk_timer(&tsk->thread.system_timer, lc->system_timer); + hardirq = update_tsk_timer(&tsk->thread.hardirq_timer, lc->hardirq_timer); + softirq = update_tsk_timer(&tsk->thread.softirq_timer, lc->softirq_timer); + lc->steal_timer += clock - user - guest - system - hardirq - softirq; /* Push account value */ if (user) { |