[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

1 files changed, 23 insertions, 0 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cc b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cc
index 0dc43758516..5f9404eac2f 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cc
+++ b/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.