Changeset 34174 in vbox for trunk/src/VBox/Runtime

Timestamp:

Nov 18, 2010 2:52:35 PM (14 years ago)

Author:

vboxsync

Message:

IPRT: Use prefer real-time signal over SIGUSR2 for RTThreadPoke. Try several ones before giving up.

Location:

trunk/src/VBox/Runtime

Files:

• r3/posix/thread-posix.cpp (modified) (9 diffs)
• testcase/Makefile.kmk (modified) (2 diffs)
• testcase/tstRTThreadPoke.cpp (added)

trunk/src/VBox/Runtime/r3/posix/thread-posix.cpp

@@ -58 +58 @@
 #ifndef IN_GUEST
 /** The signal we're using for RTThreadPoke. */
-# define RTTHREAD_POSIX_POKE_SIG    SIGUSR2
+# define RTTHREAD_POSIX_WITH_POKE    SIGUSR2
 #endif
 
@@ -67 +67 @@
 /** The pthread key in which we store the pointer to our own PRTTHREAD structure. */
 static pthread_key_t    g_SelfKey;
-#ifdef RTTHREAD_POSIX_POKE_SIG
-/** Set if we can poke a thread, clear if we cannot. */
-static bool             g_fCanPokeThread;
+#ifdef RTTHREAD_POSIX_WITH_POKE
+/** The signal we use for poking threads.
+ * This is set to -1 if no available signal was found. */
+static int              g_iSigPokeThread = -1;
 #endif
 
@@ -91 +92 @@
         return VERR_NO_TLS_FOR_SELF;
 
-#ifdef RTTHREAD_POSIX_POKE_SIG
+#ifdef RTTHREAD_POSIX_WITH_POKE
     /*
      * Try register the dummy signal handler for RTThreadPoke.
-     */
-    g_fCanPokeThread = false;
-    struct sigaction SigActOld;
-    if (!sigaction(RTTHREAD_POSIX_POKE_SIG, NULL, &SigActOld))
-    {
-        if (   SigActOld.sa_handler == SIG_DFL
-            || SigActOld.sa_handler == rtThreadPosixPokeSignal)
+     * Avoid SIGRTMIN thru SIGRTMIN+2 because of LinuxThreads.
+     */
+    static const int s_aiSigCandidates[] =
+    {
+# ifdef SIGRTMAX
+        SIGRTMAX-3,
+        SIGRTMAX-2,
+        SIGRTMAX-1,
+# endif
+        SIGUSR2,
+        SIGWINCH
+    };
+
+    g_iSigPokeThread = -1;
+    for (unsigned iSig = 0; iSig < RT_ELEMENTS(s_aiSigCandidates); iSig++)
+    {
+        struct sigaction SigActOld;
+        if (!sigaction(s_aiSigCandidates[iSig], NULL, &SigActOld))
         {
-            struct sigaction SigAct;
-            memset(&SigAct, '\0', sizeof(SigAct));
-            SigAct.sa_handler = rtThreadPosixPokeSignal;
-            sigfillset(&SigAct.sa_mask);
-            SigAct.sa_flags = 0;
-
-            /* ASSUMES no sigaction race... (lazy bird) */
-            if (!sigaction(RTTHREAD_POSIX_POKE_SIG, &SigAct, NULL))
-                g_fCanPokeThread = true;
-            else
+            if (   SigActOld.sa_handler == SIG_DFL
+                || SigActOld.sa_handler == rtThreadPosixPokeSignal)
             {
+                struct sigaction SigAct;
+                RT_ZERO(SigAct);
+                SigAct.sa_handler = rtThreadPosixPokeSignal;
+                SigAct.sa_flags   = 0;
+                sigfillset(&SigAct.sa_mask);
+
+                /* ASSUMES no sigaction race... (lazy bird) */
+                if (!sigaction(s_aiSigCandidates[iSig], &SigAct, NULL))
+                {
+                    g_iSigPokeThread = s_aiSigCandidates[iSig];
+                    break;
+                }
                 AssertMsgFailed(("rc=%Rrc errno=%d\n", RTErrConvertFromErrno(errno), errno));
-                pthread_key_delete(g_SelfKey);
-                g_SelfKey = 0;
             }
         }
-    }
-    else
-        AssertMsgFailed(("rc=%Rrc errno=%d\n", RTErrConvertFromErrno(errno), errno));
-#endif /* RTTHREAD_POSIX_POKE_SIG */
+        else
+            AssertMsgFailed(("rc=%Rrc errno=%d\n", RTErrConvertFromErrno(errno), errno));
+    }
+#endif /* RTTHREAD_POSIX_WITH_POKE */
     return rc;
 }
@@ -145 +159 @@
 
 
-#ifdef RTTHREAD_POSIX_POKE_SIG
+#ifdef RTTHREAD_POSIX_WITH_POKE
 /**
  * Dummy signal handler for the poke signal.
@@ -153 +167 @@
 static void rtThreadPosixPokeSignal(int iSignal)
 {
-    Assert(iSignal == RTTHREAD_POSIX_POKE_SIG);
+    Assert(iSignal == g_iSigPokeThread);
     NOREF(iSignal);
 }
@@ -176 +190 @@
     sigaddset(&SigSet, SIGALRM);
     sigprocmask(SIG_BLOCK, &SigSet, NULL);
-#ifdef RTTHREAD_POSIX_POKE_SIG
-    if (g_fCanPokeThread)
-        siginterrupt(RTTHREAD_POSIX_POKE_SIG, 1);
+#ifdef RTTHREAD_POSIX_WITH_POKE
+    if (g_iSigPokeThread != -1)
+        siginterrupt(g_iSigPokeThread, 1);
 #endif
 
@@ -212 +226 @@
     sigaddset(&SigSet, SIGALRM);
     sigprocmask(SIG_BLOCK, &SigSet, NULL);
-#ifdef RTTHREAD_POSIX_POKE_SIG
-    if (g_fCanPokeThread)
-        siginterrupt(RTTHREAD_POSIX_POKE_SIG, 1);
+#ifdef RTTHREAD_POSIX_WITH_POKE
+    if (g_iSigPokeThread != -1)
+        siginterrupt(g_iSigPokeThread, 1);
 #endif
 
@@ -367 +381 @@
 
 
-#ifdef RTTHREAD_POSIX_POKE_SIG
+#ifdef RTTHREAD_POSIX_WITH_POKE
 RTDECL(int) RTThreadPoke(RTTHREAD hThread)
 {
@@ -373 +387 @@
     PRTTHREADINT pThread = rtThreadGet(hThread);
     AssertReturn(pThread, VERR_INVALID_HANDLE);
+
     int rc;
-    if (g_fCanPokeThread)
-    {
-        rc = pthread_kill((pthread_t)(uintptr_t)pThread->Core.Key, RTTHREAD_POSIX_POKE_SIG);
+    if (g_iSigPokeThread != -1)
+    {
+        rc = pthread_kill((pthread_t)(uintptr_t)pThread->Core.Key, g_iSigPokeThread);
         rc = RTErrConvertFromErrno(rc);
     }

trunk/src/VBox/Runtime/testcase/Makefile.kmk

@@ -109 +109 @@
         tstTermCallbacks \
         tstThread-1 \
+        tstRTThreadPoke \
         tstTime \
         tstTime-2 \
@@ -461 +462 @@
 tstThread-1_SOURCES = tstThread-1.cpp
 
+tstRTThreadPoke_TEMPLATE = VBOXR3TSTEXE
+tstRTThreadPoke_SOURCES = tstRTThreadPoke.cpp
+
 tstTime_SOURCES = tstTime.cpp