From: Julian Seward <jseward@acm.org>
Date: Fri, 24 May 2002 00:11:16 +0000 (+0000)
Subject: Make syscall sched_yield just yield the current thread rather than the
X-Git-Tag: svn/VALGRIND_1_0_3~146
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c9295b3bfdafef6efda61af026a0a99d32d02ef7;p=thirdparty%2Fvalgrind.git

Make syscall sched_yield just yield the current thread rather than the
whole process.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@320
---

diff --git a/coregrind/vg_scheduler.c b/coregrind/vg_scheduler.c
index 801502b916..c4876f85bd 100644
--- a/coregrind/vg_scheduler.c
+++ b/coregrind/vg_scheduler.c
@@ -1388,9 +1388,18 @@ VgSchedReturnCode VG_(scheduler) ( void )
             }
 #           endif
 
+            /* Is the client exiting for good? */
             if (VG_(threads)[tid].m_eax == __NR_exit)
                return VgSrc_ExitSyscall;
 
+            /* Trap syscalls to __NR_sched_yield and just have this
+               thread yield instead.  Not essential, just an
+               optimisation. */
+	    if (VG_(threads)[tid].m_eax == __NR_sched_yield) {
+               SET_EAX(tid, 0); /* syscall returns with success */
+               goto stage1; /* find a new thread to run */
+	    }
+
             sched_do_syscall(tid);
 
 #           if 0
diff --git a/vg_scheduler.c b/vg_scheduler.c
index 801502b916..c4876f85bd 100644
--- a/vg_scheduler.c
+++ b/vg_scheduler.c
@@ -1388,9 +1388,18 @@ VgSchedReturnCode VG_(scheduler) ( void )
             }
 #           endif
 
+            /* Is the client exiting for good? */
             if (VG_(threads)[tid].m_eax == __NR_exit)
                return VgSrc_ExitSyscall;
 
+            /* Trap syscalls to __NR_sched_yield and just have this
+               thread yield instead.  Not essential, just an
+               optimisation. */
+	    if (VG_(threads)[tid].m_eax == __NR_sched_yield) {
+               SET_EAX(tid, 0); /* syscall returns with success */
+               goto stage1; /* find a new thread to run */
+	    }
+
             sched_do_syscall(tid);
 
 #           if 0