Changeset c655650 for libcfa/src/concurrency/kernel

Timestamp:

Feb 12, 2022, 1:53:14 PM (3 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, ast-experimental, enum, master, pthread-emulation, qualifiedEnum

Children:

470618c0

Parents:

aac37fa

Message:

update fast PRNG code

File:

• libcfa/src/concurrency/kernel/startup.cfa (modified) (3 diffs)

libcfa/src/concurrency/kernel/startup.cfa ¶

@@ -18 +18 @@
 
 // C Includes
-#include <errno.h>              // errno
+#include <errno.h>                                                                              // errno
 #include <signal.h>
-#include <string.h>             // strerror
-#include <unistd.h>             // sysconf
+#include <string.h>                                                                             // strerror
+#include <unistd.h>                                                                             // sysconf
 
 extern "C" {
-      #include <limits.h>       // PTHREAD_STACK_MIN
-        #include <unistd.h>       // syscall
-        #include <sys/eventfd.h>  // eventfd
-      #include <sys/mman.h>     // mprotect
-      #include <sys/resource.h> // getrlimit
+        #include <limits.h>                                                                     // PTHREAD_STACK_MIN
+        #include <unistd.h>                                                                     // syscall
+        #include <sys/eventfd.h>                                                        // eventfd
+        #include <sys/mman.h>                                                           // mprotect
+        #include <sys/resource.h>                                                       // getrlimit
 }
 
 // CFA Includes
 #include "kernel_private.hfa"
-#include "startup.hfa"          // STARTUP_PRIORITY_XXX
+#include "startup.hfa"                                                                  // STARTUP_PRIORITY_XXX
 #include "limits.hfa"
 #include "math.hfa"
@@ -102 +102 @@
 extern void __wake_proc(processor *);
 extern int cfa_main_returned;                                                   // from interpose.cfa
-extern uint32_t __global_random_seed;
+uint32_t __global_random_prime = 4_294_967_291u, __global_random_mask = false;
 
 //-----------------------------------------------------------------------------
@@ -490 +490 @@
         preferred = ready_queue_new_preferred();
         last_proc = 0p;
-        random_state = __global_random_seed;
+        random_state = __global_random_mask ? __global_random_prime : __global_random_prime ^ rdtscl();
         #if defined( __CFA_WITH_VERIFY__ )
                 canary = 0x0D15EA5E0D15EA5Ep;