9os

commit a169e5e8b958395249861cc6d64b191ea3164ef9
parent 9f6fbda00aec1be7d746dc8d118d693eecd6cec5
Author: Roberto E. Vargas Caballero <roberto.vargas@midokura.com>
Date:   Fri, 25 Nov 2022 09:47:46 +0100

os9: Add sleep() and wakeup()

Diffstat:
M
include/bits/amd64/arch/types.h
 | 
1
+
M
include/bits/arm64/arch/types.h
 | 
1
+
M
include/os9/os9.h
 | 
10
++++++++++
M
src/os9/hosted/lock.c
 | 
12
++++++++++++
M
src/os9/proc.c
 | 
39
+++++++++++++++++++++++++++++++++++++++

5 files changed, 63 insertions(+), 0 deletions(-)
diff --git a/include/bits/amd64/arch/types.h b/include/bits/amd64/arch/types.h
@@ -11,6 +11,7 @@
 
 typedef int atomic_t;
 typedef unsigned long mutex_t;
+typedef unsigned long spinlock_t;
 typedef unsigned long long phyaddr_t;
 typedef struct context Context;
 
diff --git a/include/bits/arm64/arch/types.h b/include/bits/arm64/arch/types.h
@@ -61,6 +61,7 @@ enum regidx {
 
 typedef int atomic_t;
 typedef unsigned long mutex_t;
+typedef unsigned long splinlock_t;
 typedef unsigned long long pte_t;
 typedef unsigned long long phyaddr_t;
 typedef struct context Context;
diff --git a/include/os9/os9.h b/include/os9/os9.h
@@ -52,6 +52,7 @@ typedef struct mpoint Mpoint;
 typedef struct nspace Nspace;
 typedef struct fdset Fdset;
 typedef struct ref Ref;
+typedef struct rendez Rendez;
 
 enum rforkflags {
 	RFPROC = 1 << 0,
@@ -187,6 +188,11 @@ struct fdset {
 	Fdset *next;
 };
 
+struct rendez {
+        spinlock_t s;
+        Task *task;
+};
+
 /**
  * @entry: Entry point for the task.
  * @prio:
@@ -266,6 +272,8 @@ extern Map *newstack(Task *);
 extern void sched(void);
 extern void locktask(Task *);
 extern void unlocktask(Task *);
+extern void sleep(Rendez *, int (*cond)(void *), void *);
+extern void wakeup(Rendez *);
 
 /* alloc.c */
 extern void *alloc(size_t);
@@ -316,6 +324,8 @@ extern uint32_t outm32(uint32_t, void *addr);
 extern void lock(mutex_t *m);
 extern void unlock(mutex_t *m);
 extern int trylock(mutex_t *m);
+extern void lockspin(spinlock_t *);
+extern void unlockspin(spinlock_t *);
 extern void barrier(int);
 extern noreturn void halt(void);
 extern noreturn void panic(const char *msg);
diff --git a/src/os9/hosted/lock.c b/src/os9/hosted/lock.c
@@ -1,6 +1,18 @@
 #include <os9/os9.h>
 
 void
+unlockspin(spinlock_t *s)
+{
+	unlock(s);
+}
+
+void
+lockspin(spinlock_t *s)
+{
+	lock(s);
+}
+
+void
 lock(mutex_t *mutex)
 {
 	if (!mutex)
diff --git a/src/os9/proc.c b/src/os9/proc.c
@@ -404,6 +404,45 @@ inittask(void)
 	return tp;
 }
 
+/*
+ * sleep() and wakeup() are highly inspired in
+ * the paper 'Process Sleep and Wakeup on a
+ * Shared-memory Multiprocessor'
+ */
+void
+sleep(Rendez *r, int (*cond)(void *), void *arg)
+{
+	lockspin(&r->s);
+
+	if (!(*cond)(arg)) {
+		unlockspin(&r->s);
+		return;
+	}
+
+	proc->state = TWAITING;
+	proc->next = r->task;
+	r->task = proc;
+	unlockspin(&r->s);
+	sched();
+}
+
+void
+wakeup(Rendez *r)
+{
+	Task *tp, *next;
+
+	lockspin(&r->s);
+	for (tp = r->task; tp; tp = next) {
+		if (tp->state != TWAITING)
+			panic("wakeup: not sleeping");
+		next = tp->next;
+		tp->next = NULL;
+		tp->state = TREADY;
+	}
+	r->task = NULL;
+	unlockspin(&r->s);
+}
+
 void
 iproc(void)
 {