#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <grpc/support/port_platform.h>
#ifdef GPR_CPU_LINUX
#include <errno.h>
#include <sched.h>
#include <string.h>
#include <unistd.h>
#include <grpc/support/cpu.h>
#include <grpc/support/log.h>
#include <grpc/support/sync.h>
#include "src/core/lib/gprpp/crash.h"
#include "src/core/lib/gprpp/strerror.h"
static int ncpus = 0;
static void init_num_cpus() {
#ifndef GPR_MUSL_LIBC_COMPAT
if (sched_getcpu() < 0) {
gpr_log(GPR_ERROR, "Error determining current CPU: %s\n",
grpc_core::StrError(errno).c_str());
ncpus = 1;
return;
}
#endif
ncpus = static_cast<int>(sysconf(_SC_NPROCESSORS_CONF));
if (ncpus < 1) {
gpr_log(GPR_ERROR, "Cannot determine number of CPUs: assuming 1");
ncpus = 1;
}
}
unsigned gpr_cpu_num_cores(void) {
static gpr_once once = GPR_ONCE_INIT;
gpr_once_init(&once, init_num_cpus);
return static_cast<unsigned>(ncpus);
}
unsigned gpr_cpu_current_cpu(void) {
#ifdef GPR_MUSL_LIBC_COMPAT
return 0;
#else
if (gpr_cpu_num_cores() == 1) {
return 0;
}
int cpu = sched_getcpu();
if (cpu < 0) {
gpr_log(GPR_ERROR, "Error determining current CPU: %s\n",
grpc_core::StrError(errno).c_str());
return 0;
}
if (static_cast<unsigned>(cpu) >= gpr_cpu_num_cores()) {
gpr_log(GPR_DEBUG, "Cannot handle hot-plugged CPUs");
return 0;
}
return static_cast<unsigned>(cpu);
#endif
}
#endif