From 8c2d74f03705c2c993a57673bae8fd535eabede6 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 21 Aug 2019 21:09:01 +0200 Subject: [PATCH] posix-cpu-timers: Get rid of pointer indirection Now that the sample functions have no return value anymore, the result can simply be returned instead of using pointer indirection. Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://lkml.kernel.org/r/20190821192920.535079278@linutronix.de --- kernel/time/posix-cpu-timers.c | 50 +++++++++++++++------------------- 1 file changed, 22 insertions(+), 28 deletions(-) diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index cc3d148344d3..a2007ce9322a 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -182,22 +182,19 @@ posix_cpu_clock_set(const clockid_t clock, const struct timespec64 *tp) /* * Sample a per-thread clock for the given task. clkid is validated. */ -static void cpu_clock_sample(const clockid_t clkid, struct task_struct *p, - u64 *sample) +static u64 cpu_clock_sample(const clockid_t clkid, struct task_struct *p) { switch (clkid) { case CPUCLOCK_PROF: - *sample = prof_ticks(p); - break; + return prof_ticks(p); case CPUCLOCK_VIRT: - *sample = virt_ticks(p); - break; + return virt_ticks(p); case CPUCLOCK_SCHED: - *sample = task_sched_runtime(p); - break; + return task_sched_runtime(p); default: WARN_ON_ONCE(1); } + return 0; } /* @@ -299,8 +296,8 @@ thread_group_start_cputime(struct task_struct *tsk, struct task_cputime *times) * held to protect the task traversal on a full update. clkid is already * validated. */ -static void cpu_clock_sample_group(const clockid_t clkid, struct task_struct *p, - u64 *sample, bool start) +static u64 cpu_clock_sample_group(const clockid_t clkid, struct task_struct *p, + bool start) { struct thread_group_cputimer *cputimer = &p->signal->cputimer; struct task_cputime cputime; @@ -316,17 +313,15 @@ static void cpu_clock_sample_group(const clockid_t clkid, struct task_struct *p, switch (clkid) { case CPUCLOCK_PROF: - *sample = cputime.utime + cputime.stime; - break; + return cputime.utime + cputime.stime; case CPUCLOCK_VIRT: - *sample = cputime.utime; - break; + return cputime.utime; case CPUCLOCK_SCHED: - *sample = cputime.sum_exec_runtime; - break; + return cputime.sum_exec_runtime; default: WARN_ON_ONCE(1); } + return 0; } static int posix_cpu_clock_get(const clockid_t clock, struct timespec64 *tp) @@ -340,9 +335,9 @@ static int posix_cpu_clock_get(const clockid_t clock, struct timespec64 *tp) return -EINVAL; if (CPUCLOCK_PERTHREAD(clock)) - cpu_clock_sample(clkid, tsk, &t); + t = cpu_clock_sample(clkid, tsk); else - cpu_clock_sample_group(clkid, tsk, &t, false); + t = cpu_clock_sample_group(clkid, tsk, false); put_task_struct(tsk); *tp = ns_to_timespec64(t); @@ -604,11 +599,10 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags, * times (in arm_timer). With an absolute time, we must * check if it's already passed. In short, we need a sample. */ - if (CPUCLOCK_PERTHREAD(timer->it_clock)) { - cpu_clock_sample(clkid, p, &val); - } else { - cpu_clock_sample_group(clkid, p, &val, true); - } + if (CPUCLOCK_PERTHREAD(timer->it_clock)) + val = cpu_clock_sample(clkid, p); + else + val = cpu_clock_sample_group(clkid, p, true); if (old) { if (old_expires == 0) { @@ -716,7 +710,7 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *itp * Sample the clock to take the difference with the expiry time. */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { - cpu_clock_sample(clkid, p, &now); + now = cpu_clock_sample(clkid, p); } else { struct sighand_struct *sighand; unsigned long flags; @@ -736,7 +730,7 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *itp timer->it.cpu.expires = 0; return; } else { - cpu_clock_sample_group(clkid, p, &now, false); + now = cpu_clock_sample_group(clkid, p, false); unlock_task_sighand(p, &flags); } } @@ -998,7 +992,7 @@ static void posix_cpu_timer_rearm(struct k_itimer *timer) * Fetch the current sample and update the timer's expiry time. */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { - cpu_clock_sample(clkid, p, &now); + now = cpu_clock_sample(clkid, p); bump_cpu_timer(timer, now); if (unlikely(p->exit_state)) return; @@ -1024,7 +1018,7 @@ static void posix_cpu_timer_rearm(struct k_itimer *timer) /* If the process is dying, no need to rearm */ goto unlock; } - cpu_clock_sample_group(clkid, p, &now, true); + now = cpu_clock_sample_group(clkid, p, true); bump_cpu_timer(timer, now); /* Leave the sighand locked for the call below. */ } @@ -1192,7 +1186,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, if (WARN_ON_ONCE(clock_idx >= CPUCLOCK_SCHED)) return; - cpu_clock_sample_group(clock_idx, tsk, &now, true); + now = cpu_clock_sample_group(clock_idx, tsk, true); if (oldval) { /*