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authorDave Young <dyoung@redhat.com>2012-03-28 14:42:56 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 17:14:37 -0700
commitf0f57b2b1488251970c25deea0ea150a8d0911ed (patch)
tree6a1021691892c6bfa6c7471861b87eb72cd1be1a /Documentation/vm
parent63e315535abe0d820d0e3db4c06bc5de74aeefc8 (diff)
downloadlwn-f0f57b2b1488251970c25deea0ea150a8d0911ed.tar.gz
lwn-f0f57b2b1488251970c25deea0ea150a8d0911ed.zip
mm: move hugepage test examples to tools/testing/selftests/vm
hugepage-mmap.c, hugepage-shm.c and map_hugetlb.c in Documentation/vm are simple pass/fail tests, It's better to promote them to tools/testing/selftests. Thanks suggestion of Andrew Morton about this. They all need firstly setting up proper nr_hugepages and hugepage-mmap need to mount hugetlbfs. So I add a shell script run_vmtests to do such work which will call the three test programs and check the return value of them. Changes to original code including below: a. add run_vmtests script b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition [akpm@linux-foundation.org: build the targets before trying to execute them] [akpm@linux-foundation.org: Documentation/vm/ no longer has a Makefile. Fixes "make clean"] Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/vm')
-rw-r--r--Documentation/vm/Makefile8
-rw-r--r--Documentation/vm/hugepage-mmap.c91
-rw-r--r--Documentation/vm/hugepage-shm.c98
-rw-r--r--Documentation/vm/map_hugetlb.c77
4 files changed, 0 insertions, 274 deletions
diff --git a/Documentation/vm/Makefile b/Documentation/vm/Makefile
deleted file mode 100644
index e538864bfc63..000000000000
--- a/Documentation/vm/Makefile
+++ /dev/null
@@ -1,8 +0,0 @@
-# kbuild trick to avoid linker error. Can be omitted if a module is built.
-obj- := dummy.o
-
-# List of programs to build
-hostprogs-y := hugepage-mmap hugepage-shm map_hugetlb
-
-# Tell kbuild to always build the programs
-always := $(hostprogs-y)
diff --git a/Documentation/vm/hugepage-mmap.c b/Documentation/vm/hugepage-mmap.c
deleted file mode 100644
index db0dd9a33d54..000000000000
--- a/Documentation/vm/hugepage-mmap.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- * hugepage-mmap:
- *
- * Example of using huge page memory in a user application using the mmap
- * system call. Before running this application, make sure that the
- * administrator has mounted the hugetlbfs filesystem (on some directory
- * like /mnt) using the command mount -t hugetlbfs nodev /mnt. In this
- * example, the app is requesting memory of size 256MB that is backed by
- * huge pages.
- *
- * For the ia64 architecture, the Linux kernel reserves Region number 4 for
- * huge pages. That means that if one requires a fixed address, a huge page
- * aligned address starting with 0x800000... will be required. If a fixed
- * address is not required, the kernel will select an address in the proper
- * range.
- * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-
-#define FILE_NAME "/mnt/hugepagefile"
-#define LENGTH (256UL*1024*1024)
-#define PROTECTION (PROT_READ | PROT_WRITE)
-
-/* Only ia64 requires this */
-#ifdef __ia64__
-#define ADDR (void *)(0x8000000000000000UL)
-#define FLAGS (MAP_SHARED | MAP_FIXED)
-#else
-#define ADDR (void *)(0x0UL)
-#define FLAGS (MAP_SHARED)
-#endif
-
-static void check_bytes(char *addr)
-{
- printf("First hex is %x\n", *((unsigned int *)addr));
-}
-
-static void write_bytes(char *addr)
-{
- unsigned long i;
-
- for (i = 0; i < LENGTH; i++)
- *(addr + i) = (char)i;
-}
-
-static void read_bytes(char *addr)
-{
- unsigned long i;
-
- check_bytes(addr);
- for (i = 0; i < LENGTH; i++)
- if (*(addr + i) != (char)i) {
- printf("Mismatch at %lu\n", i);
- break;
- }
-}
-
-int main(void)
-{
- void *addr;
- int fd;
-
- fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755);
- if (fd < 0) {
- perror("Open failed");
- exit(1);
- }
-
- addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0);
- if (addr == MAP_FAILED) {
- perror("mmap");
- unlink(FILE_NAME);
- exit(1);
- }
-
- printf("Returned address is %p\n", addr);
- check_bytes(addr);
- write_bytes(addr);
- read_bytes(addr);
-
- munmap(addr, LENGTH);
- close(fd);
- unlink(FILE_NAME);
-
- return 0;
-}
diff --git a/Documentation/vm/hugepage-shm.c b/Documentation/vm/hugepage-shm.c
deleted file mode 100644
index 07956d8592c9..000000000000
--- a/Documentation/vm/hugepage-shm.c
+++ /dev/null
@@ -1,98 +0,0 @@
-/*
- * hugepage-shm:
- *
- * Example of using huge page memory in a user application using Sys V shared
- * memory system calls. In this example the app is requesting 256MB of
- * memory that is backed by huge pages. The application uses the flag
- * SHM_HUGETLB in the shmget system call to inform the kernel that it is
- * requesting huge pages.
- *
- * For the ia64 architecture, the Linux kernel reserves Region number 4 for
- * huge pages. That means that if one requires a fixed address, a huge page
- * aligned address starting with 0x800000... will be required. If a fixed
- * address is not required, the kernel will select an address in the proper
- * range.
- * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
- *
- * Note: The default shared memory limit is quite low on many kernels,
- * you may need to increase it via:
- *
- * echo 268435456 > /proc/sys/kernel/shmmax
- *
- * This will increase the maximum size per shared memory segment to 256MB.
- * The other limit that you will hit eventually is shmall which is the
- * total amount of shared memory in pages. To set it to 16GB on a system
- * with a 4kB pagesize do:
- *
- * echo 4194304 > /proc/sys/kernel/shmall
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/shm.h>
-#include <sys/mman.h>
-
-#ifndef SHM_HUGETLB
-#define SHM_HUGETLB 04000
-#endif
-
-#define LENGTH (256UL*1024*1024)
-
-#define dprintf(x) printf(x)
-
-/* Only ia64 requires this */
-#ifdef __ia64__
-#define ADDR (void *)(0x8000000000000000UL)
-#define SHMAT_FLAGS (SHM_RND)
-#else
-#define ADDR (void *)(0x0UL)
-#define SHMAT_FLAGS (0)
-#endif
-
-int main(void)
-{
- int shmid;
- unsigned long i;
- char *shmaddr;
-
- if ((shmid = shmget(2, LENGTH,
- SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W)) < 0) {
- perror("shmget");
- exit(1);
- }
- printf("shmid: 0x%x\n", shmid);
-
- shmaddr = shmat(shmid, ADDR, SHMAT_FLAGS);
- if (shmaddr == (char *)-1) {
- perror("Shared memory attach failure");
- shmctl(shmid, IPC_RMID, NULL);
- exit(2);
- }
- printf("shmaddr: %p\n", shmaddr);
-
- dprintf("Starting the writes:\n");
- for (i = 0; i < LENGTH; i++) {
- shmaddr[i] = (char)(i);
- if (!(i % (1024 * 1024)))
- dprintf(".");
- }
- dprintf("\n");
-
- dprintf("Starting the Check...");
- for (i = 0; i < LENGTH; i++)
- if (shmaddr[i] != (char)i)
- printf("\nIndex %lu mismatched\n", i);
- dprintf("Done.\n");
-
- if (shmdt((const void *)shmaddr) != 0) {
- perror("Detach failure");
- shmctl(shmid, IPC_RMID, NULL);
- exit(3);
- }
-
- shmctl(shmid, IPC_RMID, NULL);
-
- return 0;
-}
diff --git a/Documentation/vm/map_hugetlb.c b/Documentation/vm/map_hugetlb.c
deleted file mode 100644
index eda1a6d3578a..000000000000
--- a/Documentation/vm/map_hugetlb.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
- * Example of using hugepage memory in a user application using the mmap
- * system call with MAP_HUGETLB flag. Before running this program make
- * sure the administrator has allocated enough default sized huge pages
- * to cover the 256 MB allocation.
- *
- * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages.
- * That means the addresses starting with 0x800000... will need to be
- * specified. Specifying a fixed address is not required on ppc64, i386
- * or x86_64.
- */
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-
-#define LENGTH (256UL*1024*1024)
-#define PROTECTION (PROT_READ | PROT_WRITE)
-
-#ifndef MAP_HUGETLB
-#define MAP_HUGETLB 0x40000 /* arch specific */
-#endif
-
-/* Only ia64 requires this */
-#ifdef __ia64__
-#define ADDR (void *)(0x8000000000000000UL)
-#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
-#else
-#define ADDR (void *)(0x0UL)
-#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
-#endif
-
-static void check_bytes(char *addr)
-{
- printf("First hex is %x\n", *((unsigned int *)addr));
-}
-
-static void write_bytes(char *addr)
-{
- unsigned long i;
-
- for (i = 0; i < LENGTH; i++)
- *(addr + i) = (char)i;
-}
-
-static void read_bytes(char *addr)
-{
- unsigned long i;
-
- check_bytes(addr);
- for (i = 0; i < LENGTH; i++)
- if (*(addr + i) != (char)i) {
- printf("Mismatch at %lu\n", i);
- break;
- }
-}
-
-int main(void)
-{
- void *addr;
-
- addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0);
- if (addr == MAP_FAILED) {
- perror("mmap");
- exit(1);
- }
-
- printf("Returned address is %p\n", addr);
- check_bytes(addr);
- write_bytes(addr);
- read_bytes(addr);
-
- munmap(addr, LENGTH);
-
- return 0;
-}