posix-cpu-timers: Switch check_*_timers() to array cache

Use the array based expiry cache in check_thread_timers() and convert the
store in check_process_timers() for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.408222378@linutronix.de

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 2c47ce6cab8cd0d1547645278c9b3d7d2124fde1..220e3c7ae849157e4382677fd82e253c8ef990d1 100644 (file)
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -778,8 +778,7 @@ static void check_thread_timers(struct task_struct *tsk,
                                struct list_head *firing)
 {
        struct list_head *timers = tsk->posix_cputimers.cpu_timers;
-       struct task_cputime *tsk_expires = &tsk->posix_cputimers.cputime_expires;
-       u64 expires, stime, utime;
+       u64 stime, utime, *expires = tsk->posix_cputimers.expiries;
        unsigned long soft;
 
        if (dl_task(tsk))
@@ -789,19 +788,14 @@ static void check_thread_timers(struct task_struct *tsk,
         * If cputime_expires is zero, then there are no active
         * per thread CPU timers.
         */
-       if (task_cputime_zero(tsk_expires))
+       if (task_cputime_zero(&tsk->posix_cputimers.cputime_expires))
                return;
 
        task_cputime(tsk, &utime, &stime);
 
-       expires = check_timers_list(timers, firing, utime + stime);
-       tsk_expires->prof_exp = expires;
-
-       expires = check_timers_list(++timers, firing, utime);
-       tsk_expires->virt_exp = expires;
-
-       tsk_expires->sched_exp = check_timers_list(++timers, firing,
-                                                  tsk->se.sum_exec_runtime);
+       *expires++ = check_timers_list(timers, firing, utime + stime);
+       *expires++ = check_timers_list(++timers, firing, utime);
+       *expires = check_timers_list(++timers, firing, tsk->se.sum_exec_runtime);
 
        /*
         * Check for the special case thread timers.
@@ -839,7 +833,8 @@ static void check_thread_timers(struct task_struct *tsk,
                        __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
                }
        }
-       if (task_cputime_zero(tsk_expires))
+
+       if (task_cputime_zero(&tsk->posix_cputimers.cputime_expires))
                tick_dep_clear_task(tsk, TICK_DEP_BIT_POSIX_TIMER);
 }
 
@@ -958,9 +953,10 @@ static void check_process_timers(struct task_struct *tsk,
                        prof_expires = x;
        }
 
-       sig->posix_cputimers.cputime_expires.prof_exp = prof_expires;
-       sig->posix_cputimers.cputime_expires.virt_exp = virt_expires;
-       sig->posix_cputimers.cputime_expires.sched_exp = sched_expires;
+       sig->posix_cputimers.expiries[CPUCLOCK_PROF] = prof_expires;
+       sig->posix_cputimers.expiries[CPUCLOCK_VIRT] = virt_expires;
+       sig->posix_cputimers.expiries[CPUCLOCK_SCHED] = sched_expires;
+
        if (task_cputime_zero(&sig->posix_cputimers.cputime_expires))
                stop_process_timers(sig);