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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2011-12-15 14:56:09 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2011-12-15 14:56:19 +0100
commit648616343cdbe904c585a6c12e323d3b3c72e46f (patch)
tree514bce1b52663db4ab5662b637c764cf3c2ed1eb /kernel/posix-cpu-timers.c
parent55b02d2f4445ad625213817a1736bf2884d32547 (diff)
[S390] cputime: add sparse checking and cleanup
Make cputime_t and cputime64_t nocast to enable sparse checking to detect incorrect use of cputime. Drop the cputime macros for simple scalar operations. The conversion macros are still needed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'kernel/posix-cpu-timers.c')
-rw-r--r--kernel/posix-cpu-timers.c132
1 files changed, 52 insertions, 80 deletions
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index e7cb76dc18f..125cb67daa2 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -78,7 +78,7 @@ static inline int cpu_time_before(const clockid_t which_clock,
if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
return now.sched < then.sched;
} else {
- return cputime_lt(now.cpu, then.cpu);
+ return now.cpu < then.cpu;
}
}
static inline void cpu_time_add(const clockid_t which_clock,
@@ -88,7 +88,7 @@ static inline void cpu_time_add(const clockid_t which_clock,
if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
acc->sched += val.sched;
} else {
- acc->cpu = cputime_add(acc->cpu, val.cpu);
+ acc->cpu += val.cpu;
}
}
static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock,
@@ -98,25 +98,12 @@ static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock,
if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
a.sched -= b.sched;
} else {
- a.cpu = cputime_sub(a.cpu, b.cpu);
+ a.cpu -= b.cpu;
}
return a;
}
/*
- * Divide and limit the result to res >= 1
- *
- * This is necessary to prevent signal delivery starvation, when the result of
- * the division would be rounded down to 0.
- */
-static inline cputime_t cputime_div_non_zero(cputime_t time, unsigned long div)
-{
- cputime_t res = cputime_div(time, div);
-
- return max_t(cputime_t, res, 1);
-}
-
-/*
* Update expiry time from increment, and increase overrun count,
* given the current clock sample.
*/
@@ -148,28 +135,26 @@ static void bump_cpu_timer(struct k_itimer *timer,
} else {
cputime_t delta, incr;
- if (cputime_lt(now.cpu, timer->it.cpu.expires.cpu))
+ if (now.cpu < timer->it.cpu.expires.cpu)
return;
incr = timer->it.cpu.incr.cpu;
- delta = cputime_sub(cputime_add(now.cpu, incr),
- timer->it.cpu.expires.cpu);
+ delta = now.cpu + incr - timer->it.cpu.expires.cpu;
/* Don't use (incr*2 < delta), incr*2 might overflow. */
- for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++)
- incr = cputime_add(incr, incr);
- for (; i >= 0; incr = cputime_halve(incr), i--) {
- if (cputime_lt(delta, incr))
+ for (i = 0; incr < delta - incr; i++)
+ incr += incr;
+ for (; i >= 0; incr = incr >> 1, i--) {
+ if (delta < incr)
continue;
- timer->it.cpu.expires.cpu =
- cputime_add(timer->it.cpu.expires.cpu, incr);
+ timer->it.cpu.expires.cpu += incr;
timer->it_overrun += 1 << i;
- delta = cputime_sub(delta, incr);
+ delta -= incr;
}
}
}
static inline cputime_t prof_ticks(struct task_struct *p)
{
- return cputime_add(p->utime, p->stime);
+ return p->utime + p->stime;
}
static inline cputime_t virt_ticks(struct task_struct *p)
{
@@ -248,8 +233,8 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
t = tsk;
do {
- times->utime = cputime_add(times->utime, t->utime);
- times->stime = cputime_add(times->stime, t->stime);
+ times->utime += t->utime;
+ times->stime += t->stime;
times->sum_exec_runtime += task_sched_runtime(t);
} while_each_thread(tsk, t);
out:
@@ -258,10 +243,10 @@ out:
static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b)
{
- if (cputime_gt(b->utime, a->utime))
+ if (b->utime > a->utime)
a->utime = b->utime;
- if (cputime_gt(b->stime, a->stime))
+ if (b->stime > a->stime)
a->stime = b->stime;
if (b->sum_exec_runtime > a->sum_exec_runtime)
@@ -306,7 +291,7 @@ static int cpu_clock_sample_group(const clockid_t which_clock,
return -EINVAL;
case CPUCLOCK_PROF:
thread_group_cputime(p, &cputime);
- cpu->cpu = cputime_add(cputime.utime, cputime.stime);
+ cpu->cpu = cputime.utime + cputime.stime;
break;
case CPUCLOCK_VIRT:
thread_group_cputime(p, &cputime);
@@ -470,26 +455,24 @@ static void cleanup_timers(struct list_head *head,
unsigned long long sum_exec_runtime)
{
struct cpu_timer_list *timer, *next;
- cputime_t ptime = cputime_add(utime, stime);
+ cputime_t ptime = utime + stime;
list_for_each_entry_safe(timer, next, head, entry) {
list_del_init(&timer->entry);
- if (cputime_lt(timer->expires.cpu, ptime)) {
- timer->expires.cpu = cputime_zero;
+ if (timer->expires.cpu < ptime) {
+ timer->expires.cpu = 0;
} else {
- timer->expires.cpu = cputime_sub(timer->expires.cpu,
- ptime);
+ timer->expires.cpu -= ptime;
}
}
++head;
list_for_each_entry_safe(timer, next, head, entry) {
list_del_init(&timer->entry);
- if (cputime_lt(timer->expires.cpu, utime)) {
- timer->expires.cpu = cputime_zero;
+ if (timer->expires.cpu < utime) {
+ timer->expires.cpu = 0;
} else {
- timer->expires.cpu = cputime_sub(timer->expires.cpu,
- utime);
+ timer->expires.cpu -= utime;
}
}
@@ -520,8 +503,7 @@ void posix_cpu_timers_exit_group(struct task_struct *tsk)
struct signal_struct *const sig = tsk->signal;
cleanup_timers(tsk->signal->cpu_timers,
- cputime_add(tsk->utime, sig->utime),
- cputime_add(tsk->stime, sig->stime),
+ tsk->utime + sig->utime, tsk->stime + sig->stime,
tsk->se.sum_exec_runtime + sig->sum_sched_runtime);
}
@@ -540,8 +522,7 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now)
static inline int expires_gt(cputime_t expires, cputime_t new_exp)
{
- return cputime_eq(expires, cputime_zero) ||
- cputime_gt(expires, new_exp);
+ return expires == 0 || expires > new_exp;
}
/*
@@ -651,7 +632,7 @@ static int cpu_timer_sample_group(const clockid_t which_clock,
default:
return -EINVAL;
case CPUCLOCK_PROF:
- cpu->cpu = cputime_add(cputime.utime, cputime.stime);
+ cpu->cpu = cputime.utime + cputime.stime;
break;
case CPUCLOCK_VIRT:
cpu->cpu = cputime.utime;
@@ -918,12 +899,12 @@ static void check_thread_timers(struct task_struct *tsk,
unsigned long soft;
maxfire = 20;
- tsk->cputime_expires.prof_exp = cputime_zero;
+ tsk->cputime_expires.prof_exp = 0;
while (!list_empty(timers)) {
struct cpu_timer_list *t = list_first_entry(timers,
struct cpu_timer_list,
entry);
- if (!--maxfire || cputime_lt(prof_ticks(tsk), t->expires.cpu)) {
+ if (!--maxfire || prof_ticks(tsk) < t->expires.cpu) {
tsk->cputime_expires.prof_exp = t->expires.cpu;
break;
}
@@ -933,12 +914,12 @@ static void check_thread_timers(struct task_struct *tsk,
++timers;
maxfire = 20;
- tsk->cputime_expires.virt_exp = cputime_zero;
+ tsk->cputime_expires.virt_exp = 0;
while (!list_empty(timers)) {
struct cpu_timer_list *t = list_first_entry(timers,
struct cpu_timer_list,
entry);
- if (!--maxfire || cputime_lt(virt_ticks(tsk), t->expires.cpu)) {
+ if (!--maxfire || virt_ticks(tsk) < t->expires.cpu) {
tsk->cputime_expires.virt_exp = t->expires.cpu;
break;
}
@@ -1009,20 +990,19 @@ static u32 onecputick;
static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
cputime_t *expires, cputime_t cur_time, int signo)
{
- if (cputime_eq(it->expires, cputime_zero))
+ if (!it->expires)
return;
- if (cputime_ge(cur_time, it->expires)) {
- if (!cputime_eq(it->incr, cputime_zero)) {
- it->expires = cputime_add(it->expires, it->incr);
+ if (cur_time >= it->expires) {
+ if (it->incr) {
+ it->expires += it->incr;
it->error += it->incr_error;
if (it->error >= onecputick) {
- it->expires = cputime_sub(it->expires,
- cputime_one_jiffy);
+ it->expires -= cputime_one_jiffy;
it->error -= onecputick;
}
} else {
- it->expires = cputime_zero;
+ it->expires = 0;
}
trace_itimer_expire(signo == SIGPROF ?
@@ -1031,9 +1011,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
__group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
}
- if (!cputime_eq(it->expires, cputime_zero) &&
- (cputime_eq(*expires, cputime_zero) ||
- cputime_lt(it->expires, *expires))) {
+ if (it->expires && (!*expires || it->expires < *expires)) {
*expires = it->expires;
}
}
@@ -1048,9 +1026,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
*/
static inline int task_cputime_zero(const struct task_cputime *cputime)
{
- if (cputime_eq(cputime->utime, cputime_zero) &&
- cputime_eq(cputime->stime, cputime_zero) &&
- cputime->sum_exec_runtime == 0)
+ if (!cputime->utime && !cputime->stime && !cputime->sum_exec_runtime)
return 1;
return 0;
}
@@ -1076,15 +1052,15 @@ static void check_process_timers(struct task_struct *tsk,
*/
thread_group_cputimer(tsk, &cputime);
utime = cputime.utime;
- ptime = cputime_add(utime, cputime.stime);
+ ptime = utime + cputime.stime;
sum_sched_runtime = cputime.sum_exec_runtime;
maxfire = 20;
- prof_expires = cputime_zero;
+ prof_expires = 0;
while (!list_empty(timers)) {
struct cpu_timer_list *tl = list_first_entry(timers,
struct cpu_timer_list,
entry);
- if (!--maxfire || cputime_lt(ptime, tl->expires.cpu)) {
+ if (!--maxfire || ptime < tl->expires.cpu) {
prof_expires = tl->expires.cpu;
break;
}
@@ -1094,12 +1070,12 @@ static void check_process_timers(struct task_struct *tsk,
++timers;
maxfire = 20;
- virt_expires = cputime_zero;
+ virt_expires = 0;
while (!list_empty(timers)) {
struct cpu_timer_list *tl = list_first_entry(timers,
struct cpu_timer_list,
entry);
- if (!--maxfire || cputime_lt(utime, tl->expires.cpu)) {
+ if (!--maxfire || utime < tl->expires.cpu) {
virt_expires = tl->expires.cpu;
break;
}
@@ -1154,8 +1130,7 @@ static void check_process_timers(struct task_struct *tsk,
}
}
x = secs_to_cputime(soft);
- if (cputime_eq(prof_expires, cputime_zero) ||
- cputime_lt(x, prof_expires)) {
+ if (!prof_expires || x < prof_expires) {
prof_expires = x;
}
}
@@ -1249,12 +1224,9 @@ out:
static inline int task_cputime_expired(const struct task_cputime *sample,
const struct task_cputime *expires)
{
- if (!cputime_eq(expires->utime, cputime_zero) &&
- cputime_ge(sample->utime, expires->utime))
+ if (expires->utime && sample->utime >= expires->utime)
return 1;
- if (!cputime_eq(expires->stime, cputime_zero) &&
- cputime_ge(cputime_add(sample->utime, sample->stime),
- expires->stime))
+ if (expires->stime && sample->utime + sample->stime >= expires->stime)
return 1;
if (expires->sum_exec_runtime != 0 &&
sample->sum_exec_runtime >= expires->sum_exec_runtime)
@@ -1389,18 +1361,18 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
* it to be relative, *newval argument is relative and we update
* it to be absolute.
*/
- if (!cputime_eq(*oldval, cputime_zero)) {
- if (cputime_le(*oldval, now.cpu)) {
+ if (*oldval) {
+ if (*oldval <= now.cpu) {
/* Just about to fire. */
*oldval = cputime_one_jiffy;
} else {
- *oldval = cputime_sub(*oldval, now.cpu);
+ *oldval -= now.cpu;
}
}
- if (cputime_eq(*newval, cputime_zero))
+ if (!*newval)
return;
- *newval = cputime_add(*newval, now.cpu);
+ *newval += now.cpu;
}
/*