diff options
| -rw-r--r-- | tools/testing/selftests/vm/hugepage-mremap.c | 46 | ||||
| -rwxr-xr-x | tools/testing/selftests/vm/run_vmtests.sh | 2 |
2 files changed, 31 insertions, 17 deletions
diff --git a/tools/testing/selftests/vm/hugepage-mremap.c b/tools/testing/selftests/vm/hugepage-mremap.c index 257df94697a5..2a7c33631a29 100644 --- a/tools/testing/selftests/vm/hugepage-mremap.c +++ b/tools/testing/selftests/vm/hugepage-mremap.c @@ -4,7 +4,11 @@ * * Example of remapping huge page memory in a user application using the * mremap system call. Code assumes a hugetlbfs filesystem is mounted - * at './huge'. The code will use 10MB worth of huge pages. + * at './huge'. The amount of memory used by this test is decided by a command + * line argument in MBs. If missing, the default amount is 10MB. + * + * To make sure the test triggers pmd sharing and goes through the 'unshare' + * path in the mremap code use 1GB (1024) or more. */ #define _GNU_SOURCE @@ -18,8 +22,10 @@ #include <linux/userfaultfd.h> #include <sys/ioctl.h> -#define LENGTH (1UL * 1024 * 1024 * 1024) +#define DEFAULT_LENGTH_MB 10UL +#define MB_TO_BYTES(x) (x * 1024 * 1024) +#define FILE_NAME "huge/hugepagefile" #define PROTECTION (PROT_READ | PROT_WRITE | PROT_EXEC) #define FLAGS (MAP_SHARED | MAP_ANONYMOUS) @@ -28,20 +34,20 @@ static void check_bytes(char *addr) printf("First hex is %x\n", *((unsigned int *)addr)); } -static void write_bytes(char *addr) +static void write_bytes(char *addr, size_t len) { unsigned long i; - for (i = 0; i < LENGTH; i++) + for (i = 0; i < len; i++) *(addr + i) = (char)i; } -static int read_bytes(char *addr) +static int read_bytes(char *addr, size_t len) { unsigned long i; check_bytes(addr); - for (i = 0; i < LENGTH; i++) + for (i = 0; i < len; i++) if (*(addr + i) != (char)i) { printf("Mismatch at %lu\n", i); return 1; @@ -99,11 +105,19 @@ static void register_region_with_uffd(char *addr, size_t len) } } -int main(void) +int main(int argc, char *argv[]) { + /* Read memory length as the first arg if valid, otherwise fallback to + * the default length. Any additional args are ignored. + */ + size_t length = argc > 1 ? (size_t)atoi(argv[1]) : 0UL; + + length = length > 0 ? length : DEFAULT_LENGTH_MB; + length = MB_TO_BYTES(length); + int ret = 0; - int fd = open("/huge/test", O_CREAT | O_RDWR, 0755); + int fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755); if (fd < 0) { perror("Open failed"); @@ -112,7 +126,7 @@ int main(void) /* mmap to a PUD aligned address to hopefully trigger pmd sharing. */ unsigned long suggested_addr = 0x7eaa40000000; - void *haddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + void *haddr = mmap((void *)suggested_addr, length, PROTECTION, MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); printf("Map haddr: Returned address is %p\n", haddr); if (haddr == MAP_FAILED) { @@ -122,7 +136,7 @@ int main(void) /* mmap again to a dummy address to hopefully trigger pmd sharing. */ suggested_addr = 0x7daa40000000; - void *daddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + void *daddr = mmap((void *)suggested_addr, length, PROTECTION, MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); printf("Map daddr: Returned address is %p\n", daddr); if (daddr == MAP_FAILED) { @@ -132,16 +146,16 @@ int main(void) suggested_addr = 0x7faa40000000; void *vaddr = - mmap((void *)suggested_addr, LENGTH, PROTECTION, FLAGS, -1, 0); + mmap((void *)suggested_addr, length, PROTECTION, FLAGS, -1, 0); printf("Map vaddr: Returned address is %p\n", vaddr); if (vaddr == MAP_FAILED) { perror("mmap2"); exit(1); } - register_region_with_uffd(haddr, LENGTH); + register_region_with_uffd(haddr, length); - void *addr = mremap(haddr, LENGTH, LENGTH, + void *addr = mremap(haddr, length, length, MREMAP_MAYMOVE | MREMAP_FIXED, vaddr); if (addr == MAP_FAILED) { perror("mremap"); @@ -150,10 +164,10 @@ int main(void) printf("Mremap: Returned address is %p\n", addr); check_bytes(addr); - write_bytes(addr); - ret = read_bytes(addr); + write_bytes(addr, length); + ret = read_bytes(addr, length); - munmap(addr, LENGTH); + munmap(addr, length); return ret; } diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index a24d30af3094..75d401741394 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -111,7 +111,7 @@ fi echo "-----------------------" echo "running hugepage-mremap" echo "-----------------------" -./hugepage-mremap +./hugepage-mremap 256 if [ $? -ne 0 ]; then echo "[FAIL]" exitcode=1 |