9os

commit e09ca953b0530280da880964f35d371fdbfc7519
parent 6e09d19535fdb94f2ed751bee214c6a8dfa7399b
Author: Roberto E. Vargas Caballero <roberto.vargas@midokura.com>
Date:   Thu, 17 Nov 2022 09:33:46 +0100

os9: Rename savectx() to dupctx() and add am64 version

Diffstat:
M
include/os9/os9.h
 | 
2
+-
M
src/os9/arch/arm64/ctx.c
 | 
15
+++++++++++++++
M
src/os9/hosted/ctx.c
 | 
2
+-
M
src/os9/proc.c
 | 
4
++--

4 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/include/os9/os9.h b/include/os9/os9.h
@@ -274,7 +274,7 @@ extern noreturn void swtch(Context *ctx);
 extern noreturn void trap(Context *ctx);
 extern Ptable *initptable(Task *);
 extern void ictx(Task *, void *);
-extern int savectx(Task *);
+extern int dupctx(Task *);
 extern char *getconf(char *);
 extern void idle(void);
 
diff --git a/src/os9/arch/arm64/ctx.c b/src/os9/arch/arm64/ctx.c
@@ -107,6 +107,21 @@ panic(const char *msg)
 	fault(msg, NULL);
 }
 
+int
+dupctx(Task *tp)
+{
+	proc->ctx.r[X29] = 1;
+	getctx(&tp->ctx);
+	tp->ctx[X29] = 0;
+
+	/*
+	 * When this function is called tp and proc are different pointers
+	 * but when the context of tp is restored and the execution comes
+	 * here then tp and proc are the same pointer
+	 */
+	return proc->ctx.r[X29];
+}
+
 void
 ictx(Task *tp, void *fn)
 {
diff --git a/src/os9/hosted/ctx.c b/src/os9/hosted/ctx.c
@@ -1,7 +1,7 @@
 #include <os9/os9.h>
 
 int
-savectx(Task *tp)
+dupctx(Task *tp)
 {
 	tp->m = 0;
 	tp->ctx.entry = proc->ctx.entry;
diff --git a/src/os9/proc.c b/src/os9/proc.c
@@ -423,10 +423,10 @@ rfork(int flags)
 		if ((tp = clone(proc)) == NULL)
 			return -1;
 		/*
-		 * if savectx() returns 0 then we are the child and
+		 * if dupctx() returns 0 then we are the child and
 		 * the mutex was already released by the parent
 		 */
-		if (savectx(tp) == 0)
+		if (dupctx(tp) == 0)
 			return 0;
 	}