Re: CVS commit: src/lib (libpthread)

[Chuck Silvers <chuq%chuq.com@localhost>]

hi,

On Mon, Jul 19, 2004 at 06:17:27AM +0000, Geoff Wing wrote:
> Geoff Wing <mason%primenet.com.au@localhost> typed:
> : Chuck Silvers <chs%netbsd.org@localhost> typed:
> :: cvs rdiff -r1.12 -r1.13 src/lib/libpthread/pthread_stack.c
> 
> It's this change that's causing a problem.  In pthread__stackid_setup():
> 
>         /* Set up an initial ucontext pointer to a "safe" area */
> -       t->pt_uc =(ucontext_t *)(void *)((char *)t->pt_stack.ss_sp + 
> -           t->pt_stack.ss_size - (pagesize/2));
> -#ifdef _UC_UCONTEXT_ALIGN
> -       t->pt_uc = (ucontext_t *)((uintptr_t)t->pt_uc & _UC_UCONTEXT_ALIGN);
> -#endif
> +       t->pt_uc = (ucontext_t *)
> +               STACK_ALIGN(STACK_GROW(t->pt_stack.ss_sp, pagesize / 2),
> +                           ~_UC_UCONTEXT_ALIGN);

yea, that doesn't do the same thing.  I'm not sure why it would matter, though.
does the attached patch fix the problem?

curiously, the regress/lib/libpthread tests don't fail for me.
I didn't try all of them, but several of the more stressful ones passed.
I'm building firefox from current pkgsrc now, I'll do some experiments
tonight.

-Chuck

Index: src/lib/libpthread/pthread_stack.c
===================================================================
RCS file: /cvsroot/src/lib/libpthread/pthread_stack.c,v
retrieving revision 1.13
diff -u -p -r1.13 pthread_stack.c
--- src/lib/libpthread/pthread_stack.c  18 Jul 2004 21:24:52 -0000      1.13
+++ src/lib/libpthread/pthread_stack.c  19 Jul 2004 13:19:53 -0000
@@ -160,6 +160,7 @@ pthread__stackid_setup(void *base, size_
        pthread_t t;
        void *redaddr;
        size_t pagesize;
+       caddr_t sp;
        int ret;
 
        t = base;
@@ -171,18 +172,18 @@ pthread__stackid_setup(void *base, size_
         */
 
        redaddr = STACK_SHRINK(STACK_MAX(base, size), pagesize);
+       t->pt_stack.ss_size = PT_STACKSIZE - 2 * pagesize;
 #ifdef __MACHINE_STACK_GROWS_UP
        t->pt_stack.ss_sp = (char *)base + pagesize;
+       sp = t->pt_stack.ss_sp;
 #else
        t->pt_stack.ss_sp = (char *)base + 2 * pagesize;
+       sp = (caddr_t)t->pt_stack.ss_sp + t->pt_stack.ss_size;
 #endif
-       t->pt_stack.ss_size = PT_STACKSIZE - 2 * pagesize;
-
 
        /* Set up an initial ucontext pointer to a "safe" area */
        t->pt_uc = (ucontext_t *)
-               STACK_ALIGN(STACK_GROW(t->pt_stack.ss_sp, pagesize / 2),
-                           ~_UC_UCONTEXT_ALIGN);
+               STACK_ALIGN(STACK_GROW(sp, pagesize / 2), ~_UC_UCONTEXT_ALIGN);
 
        /* Protect the next-to-bottom stack page as a red zone. */
        ret = mprotect(redaddr, pagesize, PROT_NONE);