The _exit syscall is used for both thread termination in NPTL applications,

and process termination in legacy applications.  Try to guess which we want
based on the presence of multiple threads.

Also implement locking when modifying the CPU list.


Signed-off-by: Paul Brook <paul@codesourcery.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6735 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 43 insertions, 6 deletions

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 40eab4e624..226ee6ca6e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -156,7 +156,6 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5,	\
 }
 
 
-#define __NR_sys_exit __NR_exit
 #define __NR_sys_uname __NR_uname
 #define __NR_sys_faccessat __NR_faccessat
 #define __NR_sys_fchmodat __NR_fchmodat
@@ -198,7 +197,6 @@ static int gettid(void) {
     return -ENOSYS;
 }
 #endif
-_syscall1(int,sys_exit,int,status)
 _syscall1(int,sys_uname,struct new_utsname *,buf)
 #if defined(TARGET_NR_faccessat) && defined(__NR_faccessat)
 _syscall4(int,sys_faccessat,int,dirfd,const char *,pathname,int,mode,int,flags)
@@ -2936,7 +2934,10 @@ static int do_fork(CPUState *env, unsigned int flags, abi_ulong newsp,
         nptl_flags = flags;
         flags &= ~CLONE_NPTL_FLAGS2;
 
-        /* TODO: Implement CLONE_CHILD_CLEARTID.  */
+        if (nptl_flags & CLONE_CHILD_CLEARTID) {
+            ts->child_tidptr = child_tidptr;
+        }
+
         if (nptl_flags & CLONE_SETTLS)
             cpu_set_tls (new_env, newtls);
 
@@ -2961,6 +2962,7 @@ static int do_fork(CPUState *env, unsigned int flags, abi_ulong newsp,
         sigprocmask(SIG_BLOCK, &sigmask, &info.sigmask);
 
         ret = pthread_create(&info.thread, &attr, clone_func, &info);
+        /* TODO: Free new CPU state if thread creation failed.  */
 
         sigprocmask(SIG_SETMASK, &info.sigmask, NULL);
         pthread_attr_destroy(&attr);
@@ -3011,7 +3013,8 @@ static int do_fork(CPUState *env, unsigned int flags, abi_ulong newsp,
             ts = (TaskState *)env->opaque;
             if (flags & CLONE_SETTLS)
                 cpu_set_tls (env, newtls);
-            /* TODO: Implement CLONE_CHILD_CLEARTID.  */
+            if (flags & CLONE_CHILD_CLEARTID)
+                ts->child_tidptr = child_tidptr;
 #endif
         } else {
             fork_end(0);
@@ -3428,12 +3431,46 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
 
     switch(num) {
     case TARGET_NR_exit:
+#ifdef USE_NPTL
+      /* In old applications this may be used to implement _exit(2).
+         However in threaded applictions it is used for thread termination,
+         and _exit_group is used for application termination.
+         Do thread termination if we have more then one thread.  */
+      /* FIXME: This probably breaks if a signal arrives.  We should probably
+         be disabling signals.  */
+      if (first_cpu->next_cpu) {
+          CPUState **lastp;
+          CPUState *p;
+
+          cpu_list_lock();
+          lastp = &first_cpu;
+          p = first_cpu;
+          while (p && p != (CPUState *)cpu_env) {
+              lastp = &p->next_cpu;
+              p = p->next_cpu;
+          }
+          /* If we didn't find the CPU for this thread then something is
+             horribly wrong.  */
+          if (!p)
+              abort();
+          /* Remove the CPU from the list.  */
+          *lastp = p->next_cpu;
+          cpu_list_unlock();
+          TaskState *ts = ((CPUState *)cpu_env)->opaque;
+          if (ts->child_tidptr) {
+              put_user_u32(0, ts->child_tidptr);
+              sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX,
+                        NULL, NULL, 0);
+          }
+          /* TODO: Free CPU state.  */
+          pthread_exit(NULL);
+      }
+#endif
 #ifdef HAVE_GPROF
         _mcleanup();
 #endif
         gdb_exit(cpu_env, arg1);
-        /* XXX: should free thread stack and CPU env */
-        sys_exit(arg1);
+        _exit(arg1);
         ret = 0; /* avoid warning */
         break;
     case TARGET_NR_read: