From: Jeremy Fitzhardinge <jeremy@valgrind.org>
Date: Sun, 9 Nov 2003 09:51:33 +0000 (+0000)
Subject: Only set the thread's status to WaitSys if we're actually waiting for
X-Git-Tag: svn/VALGRIND_2_1_0~74
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=64b080887223fd9515192697a2aef5e45db589a5;p=thirdparty%2Fvalgrind.git

Only set the thread's status to WaitSys if we're actually waiting for
a proxyLWP to complete a syscall.

Update sigaltstack test to use mmap to allocate the stack.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@2016
---

diff --git a/coregrind/vg_syscalls.c b/coregrind/vg_syscalls.c
index ab489a5936..91a3db5b9c 100644
--- a/coregrind/vg_syscalls.c
+++ b/coregrind/vg_syscalls.c
@@ -4391,10 +4391,8 @@ Bool VG_(pre_syscall) ( ThreadId tid )
       comes from.
    */
 
-   /* post_syscall expects us to be "waiting" even if we don't
-      block */
    tst->syscallno = syscallno;
-   tst->status = VgTs_WaitSys;
+   vg_assert(tst->status == VgTs_Runnable);
 
    if (syscallno < MAX_SPECIAL_SYS && special_sys[syscallno].before != NULL) {
       sys = &special_sys[syscallno];
@@ -4454,6 +4452,11 @@ Bool VG_(pre_syscall) ( ThreadId tid )
 
    VGP_POPCC(VgpCoreSysWrap);
 
+   /* If we're waiting on the syscall because it's in the hands of the
+      ProxyLWP, then set the thread state to WaitSys. */
+   if (!syscall_done)
+      tst->status = VgTs_WaitSys;
+
    return syscall_done;
 }
 
@@ -4477,7 +4480,6 @@ void VG_(post_syscall) ( ThreadId tid )
    pre_res = tst->sys_pre_res;
 
    vg_assert(syscallno != -1);			/* must be a current syscall */
-   vg_assert(tst->status == VgTs_WaitSys);	/* should be blocked waiting */
 
    if (syscallno < MAX_SPECIAL_SYS && special_sys[syscallno].before != NULL) {
       sys = &special_sys[syscallno];
@@ -4488,7 +4490,7 @@ void VG_(post_syscall) ( ThreadId tid )
       sys = &bad_sys;
       special = True;
    }
-   
+
    if (!VG_(is_kerror)(tst->m_eax) && sys->after != NULL)
       (sys->after)(tst->tid, tst);
 
diff --git a/memcheck/tests/sigaltstack.c b/memcheck/tests/sigaltstack.c
index 8f31e68ff2..c4c6549397 100644
--- a/memcheck/tests/sigaltstack.c
+++ b/memcheck/tests/sigaltstack.c
@@ -3,20 +3,22 @@
 #include <stdio.h>
 #include <malloc.h>
 #include <signal.h>
+#include <sys/mman.h>
 
 void sig_handler(int sig){
   int var;
   fprintf(stderr, "caught signal, local var is on %p\n", &var);
 }
 
-
 int main(int argv, char** argc) {
   int res, i;
   stack_t sigstk;
   struct sigaction act;
-  sigstk.ss_sp = (char *)malloc(SIGSTKSZ);
+  static const int size = SIGSTKSZ;
+  char *stk = (char *)mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+  sigstk.ss_sp = stk;
 
-  sigstk.ss_size = SIGSTKSZ;
+  sigstk.ss_size = size;
   sigstk.ss_flags = 0;
   fprintf(stderr, "calling sigaltstack, stack base is %p\n", sigstk.ss_sp);
   if (sigaltstack(&sigstk,0)<0) perror("sigaltstack");