ARM: 7616/1: cache-l2x0: aurora: Use writel_relaxed instead of writel
[linux-3.10.git] / kernel / itimer.c
index af2ec6b..8d262b4 100644 (file)
@@ -7,12 +7,12 @@
 /* These are all the functions necessary to implement itimers */
 
 #include <linux/mm.h>
-#include <linux/smp_lock.h>
 #include <linux/interrupt.h>
 #include <linux/syscalls.h>
 #include <linux/time.h>
 #include <linux/posix-timers.h>
 #include <linux/hrtimer.h>
+#include <trace/events/timer.h>
 
 #include <asm/uaccess.h>
 
@@ -42,10 +42,43 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer)
        return ktime_to_timeval(rem);
 }
 
+static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+                          struct itimerval *const value)
+{
+       cputime_t cval, cinterval;
+       struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+       spin_lock_irq(&tsk->sighand->siglock);
+
+       cval = it->expires;
+       cinterval = it->incr;
+       if (cval) {
+               struct task_cputime cputime;
+               cputime_t t;
+
+               thread_group_cputimer(tsk, &cputime);
+               if (clock_id == CPUCLOCK_PROF)
+                       t = cputime.utime + cputime.stime;
+               else
+                       /* CPUCLOCK_VIRT */
+                       t = cputime.utime;
+
+               if (cval < t)
+                       /* about to fire */
+                       cval = cputime_one_jiffy;
+               else
+                       cval = cval - t;
+       }
+
+       spin_unlock_irq(&tsk->sighand->siglock);
+
+       cputime_to_timeval(cval, &value->it_value);
+       cputime_to_timeval(cinterval, &value->it_interval);
+}
+
 int do_getitimer(int which, struct itimerval *value)
 {
        struct task_struct *tsk = current;
-       cputime_t cinterval, cval;
 
        switch (which) {
        case ITIMER_REAL:
@@ -56,53 +89,10 @@ int do_getitimer(int which, struct itimerval *value)
                spin_unlock_irq(&tsk->sighand->siglock);
                break;
        case ITIMER_VIRTUAL:
-               read_lock(&tasklist_lock);
-               spin_lock_irq(&tsk->sighand->siglock);
-               cval = tsk->signal->it_virt_expires;
-               cinterval = tsk->signal->it_virt_incr;
-               if (!cputime_eq(cval, cputime_zero)) {
-                       struct task_struct *t = tsk;
-                       cputime_t utime = tsk->signal->utime;
-                       do {
-                               utime = cputime_add(utime, t->utime);
-                               t = next_thread(t);
-                       } while (t != tsk);
-                       if (cputime_le(cval, utime)) { /* about to fire */
-                               cval = jiffies_to_cputime(1);
-                       } else {
-                               cval = cputime_sub(cval, utime);
-                       }
-               }
-               spin_unlock_irq(&tsk->sighand->siglock);
-               read_unlock(&tasklist_lock);
-               cputime_to_timeval(cval, &value->it_value);
-               cputime_to_timeval(cinterval, &value->it_interval);
+               get_cpu_itimer(tsk, CPUCLOCK_VIRT, value);
                break;
        case ITIMER_PROF:
-               read_lock(&tasklist_lock);
-               spin_lock_irq(&tsk->sighand->siglock);
-               cval = tsk->signal->it_prof_expires;
-               cinterval = tsk->signal->it_prof_incr;
-               if (!cputime_eq(cval, cputime_zero)) {
-                       struct task_struct *t = tsk;
-                       cputime_t ptime = cputime_add(tsk->signal->utime,
-                                                     tsk->signal->stime);
-                       do {
-                               ptime = cputime_add(ptime,
-                                                   cputime_add(t->utime,
-                                                               t->stime));
-                               t = next_thread(t);
-                       } while (t != tsk);
-                       if (cputime_le(cval, ptime)) { /* about to fire */
-                               cval = jiffies_to_cputime(1);
-                       } else {
-                               cval = cputime_sub(cval, ptime);
-                       }
-               }
-               spin_unlock_irq(&tsk->sighand->siglock);
-               read_unlock(&tasklist_lock);
-               cputime_to_timeval(cval, &value->it_value);
-               cputime_to_timeval(cinterval, &value->it_interval);
+               get_cpu_itimer(tsk, CPUCLOCK_PROF, value);
                break;
        default:
                return(-EINVAL);
@@ -110,7 +100,7 @@ int do_getitimer(int which, struct itimerval *value)
        return 0;
 }
 
-asmlinkage long sys_getitimer(int which, struct itimerval __user *value)
+SYSCALL_DEFINE2(getitimer, int, which, struct itimerval __user *, value)
 {
        int error = -EFAULT;
        struct itimerval get_buffer;
@@ -128,55 +118,67 @@ asmlinkage long sys_getitimer(int which, struct itimerval __user *value)
 /*
  * The timer is automagically restarted, when interval != 0
  */
-int it_real_fn(void *data)
+enum hrtimer_restart it_real_fn(struct hrtimer *timer)
 {
-       struct task_struct *tsk = (struct task_struct *) data;
-
-       send_group_sig_info(SIGALRM, SEND_SIG_PRIV, tsk);
+       struct signal_struct *sig =
+               container_of(timer, struct signal_struct, real_timer);
 
-       if (tsk->signal->it_real_incr.tv64 != 0) {
-               hrtimer_forward(&tsk->signal->real_timer,
-                               tsk->signal->real_timer.base->softirq_time,
-                               tsk->signal->it_real_incr);
+       trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0);
+       kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid);
 
-               return HRTIMER_RESTART;
-       }
        return HRTIMER_NORESTART;
 }
 
-/*
- * We do not care about correctness. We just sanitize the values so
- * the ktime_t operations which expect normalized values do not
- * break. This converts negative values to long timeouts similar to
- * the code in kernel versions < 2.6.16
- *
- * Print a limited number of warning messages when an invalid timeval
- * is detected.
- */
-static void fixup_timeval(struct timeval *tv, int interval)
+static inline u32 cputime_sub_ns(cputime_t ct, s64 real_ns)
 {
-       static int warnlimit = 10;
-       unsigned long tmp;
-
-       if (warnlimit > 0) {
-               warnlimit--;
-               printk(KERN_WARNING
-                      "setitimer: %s (pid = %d) provided "
-                      "invalid timeval %s: tv_sec = %ld tv_usec = %ld\n",
-                      current->comm, current->pid,
-                      interval ? "it_interval" : "it_value",
-                      tv->tv_sec, (long) tv->tv_usec);
-       }
+       struct timespec ts;
+       s64 cpu_ns;
 
-       tmp = tv->tv_usec;
-       if (tmp >= USEC_PER_SEC) {
-               tv->tv_usec = tmp % USEC_PER_SEC;
-               tv->tv_sec += tmp / USEC_PER_SEC;
-       }
+       cputime_to_timespec(ct, &ts);
+       cpu_ns = timespec_to_ns(&ts);
 
-       tmp = tv->tv_sec;
-       if (tmp > LONG_MAX)
-               tv->tv_sec = LONG_MAX;
+       return (cpu_ns <= real_ns) ? 0 : cpu_ns - real_ns;
+}
+
+static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+                          const struct itimerval *const value,
+                          struct itimerval *const ovalue)
+{
+       cputime_t cval, nval, cinterval, ninterval;
+       s64 ns_ninterval, ns_nval;
+       u32 error, incr_error;
+       struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+       nval = timeval_to_cputime(&value->it_value);
+       ns_nval = timeval_to_ns(&value->it_value);
+       ninterval = timeval_to_cputime(&value->it_interval);
+       ns_ninterval = timeval_to_ns(&value->it_interval);
+
+       error = cputime_sub_ns(nval, ns_nval);
+       incr_error = cputime_sub_ns(ninterval, ns_ninterval);
+
+       spin_lock_irq(&tsk->sighand->siglock);
+
+       cval = it->expires;
+       cinterval = it->incr;
+       if (cval || nval) {
+               if (nval > 0)
+                       nval += cputime_one_jiffy;
+               set_process_cpu_timer(tsk, clock_id, &nval, &cval);
+       }
+       it->expires = nval;
+       it->incr = ninterval;
+       it->error = error;
+       it->incr_error = incr_error;
+       trace_itimer_state(clock_id == CPUCLOCK_VIRT ?
+                          ITIMER_VIRTUAL : ITIMER_PROF, value, nval);
+
+       spin_unlock_irq(&tsk->sighand->siglock);
+
+       if (ovalue) {
+               cputime_to_timeval(cval, &ovalue->it_value);
+               cputime_to_timeval(cinterval, &ovalue->it_interval);
+       }
 }
 
 /*
@@ -185,37 +187,18 @@ static void fixup_timeval(struct timeval *tv, int interval)
 #define timeval_valid(t) \
        (((t)->tv_sec >= 0) && (((unsigned long) (t)->tv_usec) < USEC_PER_SEC))
 
-/*
- * Check for invalid timevals, sanitize them and print a limited
- * number of warnings.
- */
-static void check_itimerval(struct itimerval *value) {
-
-       if (unlikely(!timeval_valid(&value->it_value)))
-               fixup_timeval(&value->it_value, 0);
-
-       if (unlikely(!timeval_valid(&value->it_interval)))
-               fixup_timeval(&value->it_interval, 1);
-}
-
 int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
 {
        struct task_struct *tsk = current;
        struct hrtimer *timer;
        ktime_t expires;
-       cputime_t cval, cinterval, nval, ninterval;
 
        /*
         * Validate the timevals in value.
-        *
-        * Note: Although the spec requires that invalid values shall
-        * return -EINVAL, we just fixup the value and print a limited
-        * number of warnings in order not to break users of this
-        * historical misfeature.
-        *
-        * Scheduled for replacement in March 2007
         */
-       check_itimerval(value);
+       if (!timeval_valid(&value->it_value) ||
+           !timeval_valid(&value->it_interval))
+               return -EINVAL;
 
        switch (which) {
        case ITIMER_REAL:
@@ -232,60 +215,22 @@ again:
                        spin_unlock_irq(&tsk->sighand->siglock);
                        goto again;
                }
-               tsk->signal->it_real_incr =
-                       timeval_to_ktime(value->it_interval);
                expires = timeval_to_ktime(value->it_value);
-               if (expires.tv64 != 0)
-                       hrtimer_start(timer, expires, HRTIMER_REL);
+               if (expires.tv64 != 0) {
+                       tsk->signal->it_real_incr =
+                               timeval_to_ktime(value->it_interval);
+                       hrtimer_start(timer, expires, HRTIMER_MODE_REL);
+               } else
+                       tsk->signal->it_real_incr.tv64 = 0;
+
+               trace_itimer_state(ITIMER_REAL, value, 0);
                spin_unlock_irq(&tsk->sighand->siglock);
                break;
        case ITIMER_VIRTUAL:
-               nval = timeval_to_cputime(&value->it_value);
-               ninterval = timeval_to_cputime(&value->it_interval);
-               read_lock(&tasklist_lock);
-               spin_lock_irq(&tsk->sighand->siglock);
-               cval = tsk->signal->it_virt_expires;
-               cinterval = tsk->signal->it_virt_incr;
-               if (!cputime_eq(cval, cputime_zero) ||
-                   !cputime_eq(nval, cputime_zero)) {
-                       if (cputime_gt(nval, cputime_zero))
-                               nval = cputime_add(nval,
-                                                  jiffies_to_cputime(1));
-                       set_process_cpu_timer(tsk, CPUCLOCK_VIRT,
-                                             &nval, &cval);
-               }
-               tsk->signal->it_virt_expires = nval;
-               tsk->signal->it_virt_incr = ninterval;
-               spin_unlock_irq(&tsk->sighand->siglock);
-               read_unlock(&tasklist_lock);
-               if (ovalue) {
-                       cputime_to_timeval(cval, &ovalue->it_value);
-                       cputime_to_timeval(cinterval, &ovalue->it_interval);
-               }
+               set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue);
                break;
        case ITIMER_PROF:
-               nval = timeval_to_cputime(&value->it_value);
-               ninterval = timeval_to_cputime(&value->it_interval);
-               read_lock(&tasklist_lock);
-               spin_lock_irq(&tsk->sighand->siglock);
-               cval = tsk->signal->it_prof_expires;
-               cinterval = tsk->signal->it_prof_incr;
-               if (!cputime_eq(cval, cputime_zero) ||
-                   !cputime_eq(nval, cputime_zero)) {
-                       if (cputime_gt(nval, cputime_zero))
-                               nval = cputime_add(nval,
-                                                  jiffies_to_cputime(1));
-                       set_process_cpu_timer(tsk, CPUCLOCK_PROF,
-                                             &nval, &cval);
-               }
-               tsk->signal->it_prof_expires = nval;
-               tsk->signal->it_prof_incr = ninterval;
-               spin_unlock_irq(&tsk->sighand->siglock);
-               read_unlock(&tasklist_lock);
-               if (ovalue) {
-                       cputime_to_timeval(cval, &ovalue->it_value);
-                       cputime_to_timeval(cinterval, &ovalue->it_interval);
-               }
+               set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue);
                break;
        default:
                return -EINVAL;
@@ -330,9 +275,8 @@ unsigned int alarm_setitimer(unsigned int seconds)
        return it_old.it_value.tv_sec;
 }
 
-asmlinkage long sys_setitimer(int which,
-                             struct itimerval __user *value,
-                             struct itimerval __user *ovalue)
+SYSCALL_DEFINE3(setitimer, int, which, struct itimerval __user *, value,
+               struct itimerval __user *, ovalue)
 {
        struct itimerval set_buffer, get_buffer;
        int error;
@@ -340,14 +284,18 @@ asmlinkage long sys_setitimer(int which,
        if (value) {
                if(copy_from_user(&set_buffer, value, sizeof(set_buffer)))
                        return -EFAULT;
-       } else
-               memset((char *) &set_buffer, 0, sizeof(set_buffer));
+       } else {
+               memset(&set_buffer, 0, sizeof(set_buffer));
+               printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
+                           " Misfeature support will be removed\n",
+                           current->comm);
+       }
 
        error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
        if (error || !ovalue)
                return error;
 
        if (copy_to_user(ovalue, &get_buffer, sizeof(get_buffer)))
-               return -EFAULT; 
+               return -EFAULT;
        return 0;
 }