X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=linux%2Fsched.c;h=1c7198d279bc9f534c946f2f56b65011a88ff452;hb=HEAD;hp=cc614b123ba36408176b70293204ec5e7d0725b6;hpb=8aaf7d913a382291f2770e6ce72a8919d5441bef;p=bcachefs-tools-debian

diff --git a/linux/sched.c b/linux/sched.c
index cc614b1..1c7198d 100644
--- a/linux/sched.c
+++ b/linux/sched.c
@@ -1,9 +1,13 @@
 
+#include <stdio.h>
 #include <string.h>
 #include <sys/mman.h>
+#include <linux/futex.h>
+
+/* hack for mips: */
+#define CONFIG_RCU_HAVE_FUTEX 1
+#include <urcu/futex.h>
 
-#include <linux/math64.h>
-#include <linux/printk.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
 #include <linux/timer.h>
@@ -19,38 +23,41 @@ void __put_task_struct(struct task_struct *t)
 /* returns true if process was woken up, false if it was already running */
 int wake_up_process(struct task_struct *p)
 {
-	int ret;
+	int ret = p->state != TASK_RUNNING;
 
-	pthread_mutex_lock(&p->lock);
-	ret = p->state != TASK_RUNNING;
 	p->state = TASK_RUNNING;
-
-	pthread_cond_signal(&p->wait);
-	pthread_mutex_unlock(&p->lock);
-
+	futex(&p->state, FUTEX_WAKE|FUTEX_PRIVATE_FLAG,
+	      INT_MAX, NULL, NULL, 0);
 	return ret;
 }
 
 void schedule(void)
 {
-	rcu_quiescent_state();
+	int v;
 
-	pthread_mutex_lock(&current->lock);
-
-	while (current->state != TASK_RUNNING)
-		pthread_cond_wait(&current->wait, &current->lock);
+	rcu_quiescent_state();
 
-	pthread_mutex_unlock(&current->lock);
+	while ((v = READ_ONCE(current->state)) != TASK_RUNNING)
+		futex(&current->state, FUTEX_WAIT|FUTEX_PRIVATE_FLAG,
+		      v, NULL, NULL, 0);
 }
 
-static void process_timeout(unsigned long __data)
+struct process_timer {
+	struct timer_list timer;
+	struct task_struct *task;
+};
+
+static void process_timeout(struct timer_list *t)
 {
-	wake_up_process((struct task_struct *)__data);
+	struct process_timer *timeout =
+		container_of(t, struct process_timer, timer);
+
+	wake_up_process(timeout->task);
 }
 
 long schedule_timeout(long timeout)
 {
-	struct timer_list timer;
+	struct process_timer timer;
 	unsigned long expire;
 
 	switch (timeout)
@@ -74,7 +81,7 @@ long schedule_timeout(long timeout)
 		 * that will tell you if something is gone wrong and where.
 		 */
 		if (timeout < 0) {
-			printk(KERN_ERR "schedule_timeout: wrong timeout "
+			fprintf(stderr, "schedule_timeout: wrong timeout "
 				"value %lx\n", timeout);
 			current->state = TASK_RUNNING;
 			goto out;
@@ -83,94 +90,25 @@ long schedule_timeout(long timeout)
 
 	expire = timeout + jiffies;
 
-	setup_timer(&timer, process_timeout, (unsigned long)current);
-	mod_timer(&timer, expire);
+	timer.task = current;
+	timer_setup_on_stack(&timer.timer, process_timeout, 0);
+	mod_timer(&timer.timer, expire);
 	schedule();
-	del_timer_sync(&timer);
+	del_timer_sync(&timer.timer);
 
 	timeout = expire - jiffies;
 out:
 	return timeout < 0 ? 0 : timeout;
 }
 
-unsigned long __msecs_to_jiffies(const unsigned int m)
-{
-	/*
-	 * Negative value, means infinite timeout:
-	 */
-	if ((int)m < 0)
-		return MAX_JIFFY_OFFSET;
-	return _msecs_to_jiffies(m);
-}
-
-u64 nsecs_to_jiffies64(u64 n)
-{
-#if (NSEC_PER_SEC % HZ) == 0
-	/* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */
-	return div_u64(n, NSEC_PER_SEC / HZ);
-#elif (HZ % 512) == 0
-	/* overflow after 292 years if HZ = 1024 */
-	return div_u64(n * HZ / 512, NSEC_PER_SEC / 512);
-#else
-	/*
-	 * Generic case - optimized for cases where HZ is a multiple of 3.
-	 * overflow after 64.99 years, exact for HZ = 60, 72, 90, 120 etc.
-	 */
-	return div_u64(n * 9, (9ull * NSEC_PER_SEC + HZ / 2) / HZ);
-#endif
-}
-
-unsigned long nsecs_to_jiffies(u64 n)
-{
-	return (unsigned long)nsecs_to_jiffies64(n);
-}
-
-unsigned int jiffies_to_msecs(const unsigned long j)
-{
-#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
-	return (MSEC_PER_SEC / HZ) * j;
-#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
-	return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC);
-#else
-# if BITS_PER_LONG == 32
-	return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32;
-# else
-	return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN;
-# endif
-#endif
-}
-
-unsigned int jiffies_to_usecs(const unsigned long j)
-{
-	/*
-	 * Hz usually doesn't go much further MSEC_PER_SEC.
-	 * jiffies_to_usecs() and usecs_to_jiffies() depend on that.
-	 */
-	BUILD_BUG_ON(HZ > USEC_PER_SEC);
-
-#if !(USEC_PER_SEC % HZ)
-	return (USEC_PER_SEC / HZ) * j;
-#else
-# if BITS_PER_LONG == 32
-	return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
-# else
-	return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN;
-# endif
-#endif
-}
-
 __attribute__((constructor(101)))
 static void sched_init(void)
 {
 	struct task_struct *p = malloc(sizeof(*p));
 
-	mlockall(MCL_CURRENT|MCL_FUTURE);
-
 	memset(p, 0, sizeof(*p));
 
 	p->state	= TASK_RUNNING;
-	pthread_mutex_init(&p->lock, NULL);
-	pthread_cond_init(&p->wait, NULL);
 	atomic_set(&p->usage, 1);
 	init_completion(&p->exited);
 
@@ -180,7 +118,7 @@ static void sched_init(void)
 	rcu_register_thread();
 }
 
-#ifndef __NR_getrandom
+#ifndef SYS_getrandom
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>