[scudo] Make getNumberOfCPUs Fuchsia compliant

Summary: This change allows Fuchsia to boot properly using the Scudo allocator.

Reviewers: cryptoad, alekseyshl, krytarowski

Reviewed By: cryptoad, krytarowski

Subscribers: rnk, krytarowski, kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D39490

llvm-svn: 317822

compiler-rt/lib/sanitizer_common/sanitizer_common.h

@@ -933,6 +933,9 @@ void CheckNoDeepBind(const char *filename, int flag);
 // be used to seed a PRNG. Defaults to blocking like the underlying syscall.
 bool GetRandom(void *buffer, uptr length, bool blocking = true);
 
+// Returns the number of logical processors on the system.
+u32 GetNumberOfCPUs();
+
 }  // namespace __sanitizer
 
 inline void *operator new(__sanitizer::operator_new_size_type size,

compiler-rt/lib/sanitizer_common/sanitizer_fuchsia.cc

@@ -520,6 +520,10 @@ bool GetRandom(void *buffer, uptr length, bool blocking) {
   return true;
 }
 
+u32 GetNumberOfCPUs() {
+  return zx_system_get_num_cpus();
+}
+
 }  // namespace __sanitizer
 
 using namespace __sanitizer;  // NOLINT

compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cc

@@ -30,6 +30,7 @@
 #include <dlfcn.h>  // for dlsym()
 #include <link.h>
 #include <pthread.h>
+#include <sched.h>
 #include <signal.h>
 #include <sys/resource.h>
 #include <syslog.h>
@@ -37,9 +38,14 @@
 #if SANITIZER_FREEBSD
 #include <pthread_np.h>
 #include <osreldate.h>
+#include <sys/sysctl.h>
 #define pthread_getattr_np pthread_attr_get_np
 #endif
 
+#if SANITIZER_NETBSD
+#include <sys/sysctl.h>
+#endif
+
 #if SANITIZER_LINUX
 #include <sys/prctl.h>
 #endif
@@ -538,6 +544,23 @@ uptr GetRSS() {
   return rss * GetPageSizeCached();
 }
 
+// sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used as they allocate memory.
+u32 GetNumberOfCPUs() {
+#if SANITIZER_FREEBSD || SANITIZER_NETBSD
+  u32 ncpu;
+  int req[2];
+  size_t len = sizeof(ncpu);
+  req[0] = CTL_HW;
+  req[1] = HW_NCPU;
+  CHECK_EQ(sysctl(req, 2, &ncpu, &len, NULL, 0), 0);
+  return ncpu;
+#else
+  cpu_set_t CPUs;
+  CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
+  return CPU_COUNT(&CPUs);
+#endif
+}
+
 // 64-bit Android targets don't provide the deprecated __android_log_write.
 // Starting with the L release, syslog() works and is preferable to
 // __android_log_write.

compiler-rt/lib/sanitizer_common/sanitizer_mac.cc

@@ -1000,6 +1000,11 @@ bool GetRandom(void *buffer, uptr length, bool blocking) {
   UNIMPLEMENTED();
 }
 
+// FIXME: implement on this platform.
+u32 GetNumberOfCPUs() {
+  UNIMPLEMENTED();
+}
+
 }  // namespace __sanitizer
 
 #endif  // SANITIZER_MAC

compiler-rt/lib/sanitizer_common/sanitizer_win.cc

@@ -1093,6 +1093,11 @@ bool GetRandom(void *buffer, uptr length, bool blocking) {
   UNIMPLEMENTED();
 }
 
+// FIXME: implement on this platform.
+u32 GetNumberOfCPUs() {
+  UNIMPLEMENTED();
+}
+
 }  // namespace __sanitizer
 
 #endif  // _WIN32

compiler-rt/lib/scudo/scudo_tsd_shared.cpp

@@ -24,17 +24,10 @@ static atomic_uint32_t CurrentIndex;
 static ScudoTSD *TSDs;
 static u32 NumberOfTSDs;
 
-// sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used as they allocate memory.
-static u32 getNumberOfCPUs() {
-  cpu_set_t CPUs;
-  CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
-  return CPU_COUNT(&CPUs);
-}
-
 static void initOnce() {
   CHECK_EQ(pthread_key_create(&PThreadKey, NULL), 0);
   initScudo();
-  NumberOfTSDs = Min(Max(1U, getNumberOfCPUs()),
+  NumberOfTSDs = Min(Max(1U, GetNumberOfCPUs()),
                      static_cast<u32>(SCUDO_SHARED_TSD_POOL_SIZE));
   TSDs = reinterpret_cast<ScudoTSD *>(
       MmapOrDie(sizeof(ScudoTSD) * NumberOfTSDs, "ScudoTSDs"));