svn commit: r215675 - head/sys/compat/linux

[Alexander Leidinger]

Author: netchild
Date: Mon Nov 22 12:42:32 2010
New Revision: 215675
URL: http://svn.freebsd.org/changeset/base/215675

Log:
  Do not take the process lock. The assignment to u_short inside the
  properly aligned structure is atomic on all supported architectures, and
  the thread that should see side-effect of assignment is the same thread
  that does assignment.
  
  Use a more appropriate conditional to detect the linux ABI.
  
  Suggested by:	kib
  X-MFC:		together with r215664

Modified:
  head/sys/compat/linux/linux_emul.c

Modified: head/sys/compat/linux/linux_emul.c
==============================================================================
--- head/sys/compat/linux/linux_emul.c	Mon Nov 22 12:33:48 2010	(r215674)
+++ head/sys/compat/linux/linux_emul.c	Mon Nov 22 12:42:32 2010	(r215675)
@@ -198,11 +198,8 @@ linux_proc_exit(void *arg __unused, stru
 	} else	
 		EMUL_SHARED_WUNLOCK(&emul_shared_lock);
 
-	if ((shared_flags & EMUL_SHARED_HASXSTAT) != 0) {
-		PROC_LOCK(p);
+	if ((shared_flags & EMUL_SHARED_HASXSTAT) != 0)
 		p->p_xstat = shared_xstat;
-		PROC_UNLOCK(p);
-	}
 
 	if (child_clear_tid != NULL) {
 		struct linux_sys_futex_args cup;
@@ -265,7 +262,8 @@ linux_proc_exec(void *arg __unused, stru
 	if (__predict_false(imgp->sysent == &elf_linux_sysvec
 	    && p->p_sysent != &elf_linux_sysvec))
 		linux_proc_init(FIRST_THREAD_IN_PROC(p), p->p_pid, 0);
-	if (__predict_false(p->p_sysent == &elf_linux_sysvec))
+	if (__predict_false((p->p_sysent->sv_flags & SV_ABI_MASK) ==
+	    SV_ABI_LINUX))
 		/* Kill threads regardless of imgp->sysent value */
 		linux_kill_threads(FIRST_THREAD_IN_PROC(p), SIGKILL);
 	if (__predict_false(imgp->sysent != &elf_linux_sysvec