jdk8-mips64-public/hotspot: comparison src/os/bsd/vm/os

-:da65bbf6f89e
+:f73af4455d7d
 // for timer info max values which include all bits
 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
 #define LARGEPAGES_BIT (1 << 6)
+PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
 ////////////////////////////////////////////////////////////////////////////////
 // global variables
 julong os::Bsd::_physical_memory = 0;
+#ifdef __APPLE__
+mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
+volatile uint64_t         os::Bsd::_max_abstime   = 0;
+#else
 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
+#endif
 pthread_t os::Bsd::_main_thread;
 int os::Bsd::_page_size = -1;
 static jlong initial_time_count=0;
 int status = gettimeofday(&time, NULL);
 assert(status != -1, "bsd error");
 return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
 }
+#ifndef __APPLE__
 #ifndef CLOCK_MONOTONIC
 #define CLOCK_MONOTONIC (1)
 #endif
+#endif
 #ifdef __APPLE__
 void os::Bsd::clock_init() {
-// XXXDARWIN: Investigate replacement monotonic clock
+mach_timebase_info(&_timebase_info);
 }
 #else
 void os::Bsd::clock_init() {
 struct timespec res;
 struct timespec tp;
 }
 }
 #endif
+#ifdef __APPLE__
+jlong os::javaTimeNanos() {
+const uint64_t tm = mach_absolute_time();
+const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
+const uint64_t prev = Bsd::_max_abstime;
+if (now <= prev) {
+return prev;   // same or retrograde time;
+}
+const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
+assert(obsv >= prev, "invariant");   // Monotonicity
+// If the CAS succeeded then we're done and return "now".
+// If the CAS failed and the observed value "obsv" is >= now then
+// we should return "obsv".  If the CAS failed and now > obsv > prv then
+// some other thread raced this thread and installed a new value, in which case
+// we could either (a) retry the entire operation, (b) retry trying to install now
+// or (c) just return obsv.  We use (c).   No loop is required although in some cases
+// we might discard a higher "now" value in deference to a slightly lower but freshly
+// installed obsv value.   That's entirely benign -- it admits no new orderings compared
+// to (a) or (b) -- and greatly reduces coherence traffic.
+// We might also condition (c) on the magnitude of the delta between obsv and now.
+// Avoiding excessive CAS operations to hot RW locations is critical.
+// See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
+return (prev == obsv) ? now : obsv;
+}
+#else // __APPLE__
 jlong os::javaTimeNanos() {
 if (Bsd::supports_monotonic_clock()) {
 struct timespec tp;
-int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
+int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
 assert(status == 0, "gettime error");
 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
 return result;
 } else {
 timeval time;
 assert(status != -1, "bsd error");
 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
 return 1000 * usecs;
 }
 }
+#endif // __APPLE__
 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
 if (Bsd::supports_monotonic_clock()) {
 info_ptr->max_value = ALL_64_BITS;
 bool warn_on_failure = UseLargePages &&
 (!FLAG_IS_DEFAULT(UseLargePages) ||
 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
 );
-char msg[128];
 // Create a large shared memory region to attach to based on size.
 // Currently, size is the total size of the heap
 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
 if (shmid == -1) {
 //      Note 2: it's possible there's enough physical memory available but
 //            they are so fragmented after a long run that they can't
 //            coalesce into large pages. Try to reserve large pages when
 //            the system is still "fresh".
 if (warn_on_failure) {
-jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
+warning("Failed to reserve shared memory (errno = %d).", errno);
-warning(msg);
 }
 return NULL;
 }
 // attach to the region
 // segment immediately.
 shmctl(shmid, IPC_RMID, NULL);
 if ((intptr_t)addr == -1) {
 if (warn_on_failure) {
-jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
+warning("Failed to attach shared memory (errno = %d).", err);
-warning(msg);
 }
 return NULL;
 }
 // The memory is committed
 bool os::check_heap(bool force) {
 return true;
 }
+ATTRIBUTE_PRINTF(3, 0)
 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
 return ::vsnprintf(buf, count, format, args);
 }
 // Is a (classpath) directory empty?

comparison: src/os/bsd/vm/os_bsd.cpp

src/os/bsd/vm/os_bsd.cpp

Mercurial > jdk8-mips64-public > hotspot / file comparison

comparison: src/os/bsd/vm/os_bsd.cpp

src/os/bsd/vm/os_bsd.cpp