add back /proc/cpuinfo as a fallback for some platforms
diff --git a/src/sysinfo.cc b/src/sysinfo.cc
index 2787e87..4fb3261 100644
--- a/src/sysinfo.cc
+++ b/src/sysinfo.cc
@@ -508,6 +508,55 @@
hardware_threads.max_hthreads = 1;
}
return hardware_threads.max_hthreads;
+#else
+ // Fallback for platforms (such as WASM) that aren't covered above.
+ int num_cpus = 0;
+ int max_id = -1;
+ std::ifstream f("/proc/cpuinfo");
+ if (!f.is_open()) {
+ std::cerr << "Failed to open /proc/cpuinfo\n";
+ return -1;
+ }
+#if defined(__alpha__)
+ const std::string Key = "cpus detected";
+#else
+ const std::string Key = "processor";
+#endif
+ std::string ln;
+ while (std::getline(f, ln)) {
+ if (ln.empty()) continue;
+ std::size_t split_idx = ln.find(':');
+ std::string value;
+#if defined(__s390__)
+ // s390 has another format in /proc/cpuinfo
+ // it needs to be parsed differently
+ if (split_idx != std::string::npos)
+ value = ln.substr(Key.size() + 1, split_idx - Key.size() - 1);
+#else
+ if (split_idx != std::string::npos) value = ln.substr(split_idx + 1);
+#endif
+ if (ln.size() >= Key.size() && ln.compare(0, Key.size(), Key) == 0) {
+ num_cpus++;
+ if (!value.empty()) {
+ const int cur_id = benchmark::stoi(value);
+ max_id = std::max(cur_id, max_id);
+ }
+ }
+ }
+ if (f.bad()) {
+ PrintErrorAndDie("Failure reading /proc/cpuinfo");
+ }
+ if (!f.eof()) {
+ PrintErrorAndDie("Failed to read to end of /proc/cpuinfo");
+ }
+ f.close();
+
+ if ((max_id + 1) != num_cpus) {
+ fprintf(stderr,
+ "CPU ID assignments in /proc/cpuinfo seem messed up."
+ " This is usually caused by a bad BIOS.\n");
+ }
+ return num_cpus;
#endif
BENCHMARK_UNREACHABLE();
}
@@ -516,7 +565,7 @@
int num_cpus = GetNumCPUsImpl();
if (num_cpus < 1) {
std::cerr << "Unable to extract number of CPUs.\n";
- /* There is at least one CPU which we run on. */
+ // There must be at least one CPU on which we're running.
num_cpus = 1;
}
return num_cpus;
