Changes in libcfa/src/interpose.cfa [92bfda0:6011658]

File:

• libcfa/src/interpose.cfa (modified) (4 diffs)

libcfa/src/interpose.cfa

@@ -125 +125 @@
 
                 // Failure handler
-                 // internal errors
-                __cfaabi_sigaction( SIGSEGV, sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Invalid memory reference (default: Core)
-                __cfaabi_sigaction( SIGBUS , sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Bus error, bad memory access (default: Core)
-                __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO | SA_ONSTACK ); // Illegal Instruction (default: Core)
-                __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO | SA_ONSTACK ); // Floating-point exception (default: Core)
-
-                // handlers to outside errors
-                // reset in-case they insist and send it over and over
-                __cfaabi_sigaction( SIGTERM, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Termination signal (default: Term)
-                __cfaabi_sigaction( SIGINT , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Interrupt from keyboard (default: Term)
-                __cfaabi_sigaction( SIGHUP , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Hangup detected on controlling terminal or death of controlling process (default: Term)
-                __cfaabi_sigaction( SIGQUIT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Quit from keyboard (default: Core)
-                __cfaabi_sigaction( SIGABRT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Abort signal from abort(3) (default: Core)
+                __cfaabi_sigaction( SIGSEGV, sigHandler_segv, SA_SIGINFO | SA_ONSTACK );
+                __cfaabi_sigaction( SIGBUS , sigHandler_segv, SA_SIGINFO | SA_ONSTACK );
+                __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO | SA_ONSTACK );
+                __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO | SA_ONSTACK );
+                __cfaabi_sigaction( SIGTERM, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // one shot handler, return to default
+                __cfaabi_sigaction( SIGINT , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND );
+                __cfaabi_sigaction( SIGABRT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND );
+                __cfaabi_sigaction( SIGHUP , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // terminal hangup
         }
 }
@@ -168 +163 @@
 }
 
-// See concurrency/kernel.cfa and concurrency/preemption.cfa for strong definition used in multi-processor mode.
-void __kernel_abort_lock( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
-void __kernel_abort_msg( char buffer[], int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
-int __kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; }
+void * kernel_abort( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 0p; }
+void kernel_abort_msg( void * data, char buffer[], int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
+// See concurrency/kernel.cfa for strong definition used in multi-processor mode.
+int kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; }
 
 enum { abort_text_size = 1024 };
@@ -178 +173 @@
 static void __cfaabi_backtrace( int start ) {
         enum { Frames = 50, };                                                          // maximum number of stack frames
-        int last = __kernel_abort_lastframe();                          // skip last N stack frames
+        int last = kernel_abort_lastframe();                            // skip last N stack frames
 
         void * array[Frames];
@@ -225 +220 @@
 }
 
-static volatile bool __abort_first = 0;
+static volatile int __abort_stage = 0;
 
 // Cannot forward va_list.
 void __abort( bool signalAbort, const char fmt[], va_list args ) {
-        // Multiple threads can come here from multiple paths
-        // To make sure this is safe any concurrent/subsequent call to abort is redirected to libc-abort
-        bool first = ! __atomic_test_and_set( &__abort_first, __ATOMIC_SEQ_CST);
-
-        // Prevent preemption from kicking-in and messing with the abort
-        __kernel_abort_lock();
-
-        // first to abort ?
-        if ( !first ) {
-                // We aren't the first to abort just let C handle it
-                signal( SIGABRT, SIG_DFL );     // restore default in case we came here through the function.
+        int stage = __atomic_add_fetch( &__abort_stage, 1, __ATOMIC_SEQ_CST );
+
+        // First stage: stop the cforall kernel and print
+        if(stage == 1) {
+                // increment stage
+                stage = __atomic_add_fetch( &__abort_stage, 1, __ATOMIC_SEQ_CST );
+
+                // must be done here to lock down kernel
+                void * kernel_data = kernel_abort();
+                int len;
+
+                signal( SIGABRT, SIG_DFL );                                                     // prevent final "real" abort from recursing to handler
+
+                len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid)
+                __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
+
+                assert( fmt );
+                len = vsnprintf( abort_text, abort_text_size, fmt, args );
+                __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
+
+                // add optional newline if missing at the end of the format text
+                if ( fmt[strlen( fmt ) - 1] != '\n' ) {
+                        __cfaabi_bits_write( STDERR_FILENO, "\n", 1 );
+                } // if
+                kernel_abort_msg( kernel_data, abort_text, abort_text_size );
+        }
+
+        // Second stage: print the backtrace
+        if(stage == 2) {
+                // increment stage
+                stage = __atomic_add_fetch( &__abort_stage, 1, __ATOMIC_SEQ_CST );
+
+                // print stack trace in handler
+                __cfaabi_backtrace( signalAbort ? 4 : 2 );
+        }
+
+        do {
+                // Finally call abort
                 __cabi_libc.abort();
-        }
-
-        int len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid)
-        __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
-
-        // print the cause of the error
-        assert( fmt );
-        len = vsnprintf( abort_text, abort_text_size, fmt, args );
-        __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
-
-        // add optional newline if missing at the end of the format text
-        if ( fmt[strlen( fmt ) - 1] != '\n' ) {
-                __cfaabi_bits_write( STDERR_FILENO, "\n", 1 );
-        } // if
-
-        // Give the kernel the chance to add some data in here
-        __kernel_abort_msg( abort_text, abort_text_size );
-
-        // print stack trace in handler
-        __cfaabi_backtrace( signalAbort ? 4 : 2 );
-
-        // Finally call abort
-        __cabi_libc.abort();
-
+
+                // Loop so that we never return
+        } while(true);
 }