author: Jeff Dike <jdike@addtoit.com> 2006-09-27 01:50:40 -0700
committer: Linus Torvalds <torvalds@g5.osdl.org> 2006-09-27 08:26:16 -0700
commit: 3c9173509985b957bea692ea887a8a0e5055cfe8
parent: 0915ee38c7db57ff41a7a68bcc02d0dd3b7b849b
Commit Summary:
Diffstat:
1 file changed, 16 insertions, 45 deletions
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 42e3d1ed802c..cb9ab54146cc 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -444,56 +444,22 @@ void map_stub_pages(int fd, unsigned long code,
}
}
-void new_thread(void *stack, void **switch_buf_ptr, void **fork_buf_ptr,
- void (*handler)(int))
+void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
{
- unsigned long flags;
- jmp_buf switch_buf, fork_buf;
-
- *switch_buf_ptr = &switch_buf;
- *fork_buf_ptr = &fork_buf;
-
- /* Somewhat subtle - siglongjmp restores the signal mask before doing
- * the longjmp. This means that when jumping from one stack to another
- * when the target stack has interrupts enabled, an interrupt may occur
- * on the source stack. This is bad when starting up a process because
- * it's not supposed to get timer ticks until it has been scheduled.
- * So, we disable interrupts around the sigsetjmp to ensure that
- * they can't happen until we get back here where they are safe.
- */
- flags = get_signals();
- block_signals();
- if(UML_SETJMP(&fork_buf) == 0)
- new_thread_proc(stack, handler);
-
- remove_sigstack();
-
- set_signals(flags);
+ (*buf)[0].JB_IP = (unsigned long) handler;
+ (*buf)[0].JB_SP = (unsigned long) stack +
+ (PAGE_SIZE << UML_CONFIG_KERNEL_STACK_ORDER) - sizeof(void *);
}
#define INIT_JMP_NEW_THREAD 0
-#define INIT_JMP_REMOVE_SIGSTACK 1
-#define INIT_JMP_CALLBACK 2
-#define INIT_JMP_HALT 3
-#define INIT_JMP_REBOOT 4
-
-void thread_wait(void *sw, void *fb)
-{
- jmp_buf buf, **switch_buf = sw, *fork_buf;
-
- *switch_buf = &buf;
- fork_buf = fb;
- if(UML_SETJMP(&buf) == 0)
- UML_LONGJMP(fork_buf, INIT_JMP_REMOVE_SIGSTACK);
-}
+#define INIT_JMP_CALLBACK 1
+#define INIT_JMP_HALT 2
+#define INIT_JMP_REBOOT 3
-void switch_threads(void *me, void *next)
+void switch_threads(jmp_buf *me, jmp_buf *you)
{
- jmp_buf my_buf, **me_ptr = me, *next_buf = next;
-
- *me_ptr = &my_buf;
- if(UML_SETJMP(&my_buf) == 0)
- UML_LONGJMP(next_buf, 1);
+ if(UML_SETJMP(me) == 0)
+ UML_LONGJMP(you, 1);
}
static jmp_buf initial_jmpbuf;
@@ -503,23 +469,21 @@ static void (*cb_proc)(void *arg);
static void *cb_arg;
static jmp_buf *cb_back;
-int start_idle_thread(void *stack, void *switch_buf_ptr, void **fork_buf_ptr)
+int start_idle_thread(void *stack, jmp_buf *switch_buf)
{
- jmp_buf **switch_buf = switch_buf_ptr;
int n;
set_handler(SIGWINCH, (__sighandler_t) sig_handler,
SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGALRM,
SIGVTALRM, -1);
- *fork_buf_ptr = &initial_jmpbuf;
n = UML_SETJMP(&initial_jmpbuf);
switch(n){
case INIT_JMP_NEW_THREAD:
- new_thread_proc((void *) stack, new_thread_handler);
- break;
- case INIT_JMP_REMOVE_SIGSTACK:
- remove_sigstack();
+ (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler;
+ (*switch_buf)[0].JB_SP = (unsigned long) stack +
+ (PAGE_SIZE << UML_CONFIG_KERNEL_STACK_ORDER) -
+ sizeof(void *);
break;
case INIT_JMP_CALLBACK:
(*cb_proc)(cb_arg);
@@ -534,7 +498,7 @@ int start_idle_thread(void *stack, void *switch_buf_ptr, void **fork_buf_ptr)
default:
panic("Bad sigsetjmp return in start_idle_thread - %d\n", n);
}
- UML_LONGJMP(*switch_buf, 1);
+ UML_LONGJMP(switch_buf, 1);
}
void initial_thread_cb_skas(void (*proc)(void *), void *arg)