Files
rocm-systems/src/misc/shmutils.cc
T

91 строка
2.8 KiB
C++

/*************************************************************************
* Copyright (c) 2016-2022, NVIDIA CORPORATION. All rights reserved.
*
* See LICENSE.txt for license information
************************************************************************/
#include "shm.h"
#include "checks.h"
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
// Change functions behavior to match other SYS functions
static int shm_allocate(int fd, const int shmSize) {
int err = posix_fallocate(fd, 0, shmSize);
if (err) { errno = err; return -1; }
return 0;
}
static int shm_map(int fd, const int shmSize, void** ptr) {
*ptr = mmap(NULL, shmSize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
return (*ptr == MAP_FAILED) ? -1 : 0;
}
static ncclResult_t ncclShmSetup(char* shmPath, const int shmSize, int* fd, void** ptr, int create) {
if (create) {
if (shmPath[0] == '\0') {
sprintf(shmPath, "/dev/shm/nccl-XXXXXX");
*fd = mkstemp(shmPath);
} else {
SYSCHECKVAL(open(shmPath, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR), "open", *fd);
}
if (ftruncate(*fd, shmSize) != 0) {
WARN("Error: failed to extend %s to %d bytes", shmPath, shmSize);
return ncclSystemError;
}
} else {
SYSCHECKVAL(open(shmPath, O_RDWR, S_IRUSR | S_IWUSR), "open", *fd);
}
*ptr = (char*)mmap(NULL, shmSize, PROT_READ|PROT_WRITE, MAP_SHARED, *fd, 0);
if (*ptr == NULL) {
WARN("Could not map %s\n", shmPath);
return ncclSystemError;
}
close(*fd);
*fd = -1;
if (create) memset(*ptr, 0, shmSize);
return ncclSuccess;
}
ncclResult_t ncclShmOpen(char* shmPath, const int shmSize, void** shmPtr, void** devShmPtr, int create) {
int fd = -1;
void* ptr = MAP_FAILED;
ncclResult_t res = ncclSuccess;
NCCLCHECKGOTO(ncclShmSetup(shmPath, shmSize, &fd, &ptr, create), res, sysError);
if (devShmPtr) {
CUDACHECKGOTO(hipHostRegister(ptr, shmSize, hipHostRegisterMapped), res, hipError_t);
CUDACHECKGOTO(hipHostGetDevicePointer(devShmPtr, ptr, 0), res, hipError_t);
}
*shmPtr = ptr;
return ncclSuccess;
sysError:
WARN("Error while %s shared memory segment %s (size %d)", create ? "creating" : "attaching to", shmPath, shmSize);
hipError_t:
if (fd != -1) close(fd);
if (create) shm_unlink(shmPath);
if (ptr != MAP_FAILED) munmap(ptr, shmSize);
*shmPtr = NULL;
return res;
}
ncclResult_t ncclShmUnlink(const char* shmPath) {
if (shmPath != NULL) SYSCHECK(unlink(shmPath), "unlink");
return ncclSuccess;
}
ncclResult_t ncclShmClose(void* shmPtr, void* devShmPtr, const int shmSize) {
if (devShmPtr) CUDACHECK(hipHostUnregister(shmPtr));
if (munmap(shmPtr, shmSize) != 0) {
WARN("munmap of shared memory failed");
return ncclSystemError;
}
return ncclSuccess;
}