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authorDave Young <dyoung@redhat.com>2012-03-28 17:42:56 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 20:14:37 -0400
commitf0f57b2b1488251970c25deea0ea150a8d0911ed (patch)
tree6a1021691892c6bfa6c7471861b87eb72cd1be1a /Documentation/vm
parent63e315535abe0d820d0e3db4c06bc5de74aeefc8 (diff)
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 e538864bfc6..00000000000
--- a/Documentation/vm/Makefile
+++ /dev/null
@@ -1,8 +0,0 @@
1# kbuild trick to avoid linker error. Can be omitted if a module is built.
2obj- := dummy.o
3
4# List of programs to build
5hostprogs-y := hugepage-mmap hugepage-shm map_hugetlb
6
7# Tell kbuild to always build the programs
8always := $(hostprogs-y)
diff --git a/Documentation/vm/hugepage-mmap.c b/Documentation/vm/hugepage-mmap.c
deleted file mode 100644
index db0dd9a33d5..00000000000
--- a/Documentation/vm/hugepage-mmap.c
+++ /dev/null
@@ -1,91 +0,0 @@
1/*
2 * hugepage-mmap:
3 *
4 * Example of using huge page memory in a user application using the mmap
5 * system call. Before running this application, make sure that the
6 * administrator has mounted the hugetlbfs filesystem (on some directory
7 * like /mnt) using the command mount -t hugetlbfs nodev /mnt. In this
8 * example, the app is requesting memory of size 256MB that is backed by
9 * huge pages.
10 *
11 * For the ia64 architecture, the Linux kernel reserves Region number 4 for
12 * huge pages. That means that if one requires a fixed address, a huge page
13 * aligned address starting with 0x800000... will be required. If a fixed
14 * address is not required, the kernel will select an address in the proper
15 * range.
16 * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
17 */
18
19#include <stdlib.h>
20#include <stdio.h>
21#include <unistd.h>
22#include <sys/mman.h>
23#include <fcntl.h>
24
25#define FILE_NAME "/mnt/hugepagefile"
26#define LENGTH (256UL*1024*1024)
27#define PROTECTION (PROT_READ | PROT_WRITE)
28
29/* Only ia64 requires this */
30#ifdef __ia64__
31#define ADDR (void *)(0x8000000000000000UL)
32#define FLAGS (MAP_SHARED | MAP_FIXED)
33#else
34#define ADDR (void *)(0x0UL)
35#define FLAGS (MAP_SHARED)
36#endif
37
38static void check_bytes(char *addr)
39{
40 printf("First hex is %x\n", *((unsigned int *)addr));
41}
42
43static void write_bytes(char *addr)
44{
45 unsigned long i;
46
47 for (i = 0; i < LENGTH; i++)
48 *(addr + i) = (char)i;
49}
50
51static void read_bytes(char *addr)
52{
53 unsigned long i;
54
55 check_bytes(addr);
56 for (i = 0; i < LENGTH; i++)
57 if (*(addr + i) != (char)i) {
58 printf("Mismatch at %lu\n", i);
59 break;
60 }
61}
62
63int main(void)
64{
65 void *addr;
66 int fd;
67
68 fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755);
69 if (fd < 0) {
70 perror("Open failed");
71 exit(1);
72 }
73
74 addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0);
75 if (addr == MAP_FAILED) {
76 perror("mmap");
77 unlink(FILE_NAME);
78 exit(1);
79 }
80
81 printf("Returned address is %p\n", addr);
82 check_bytes(addr);
83 write_bytes(addr);
84 read_bytes(addr);
85
86 munmap(addr, LENGTH);
87 close(fd);
88 unlink(FILE_NAME);
89
90 return 0;
91}
diff --git a/Documentation/vm/hugepage-shm.c b/Documentation/vm/hugepage-shm.c
deleted file mode 100644
index 07956d8592c..00000000000
--- a/Documentation/vm/hugepage-shm.c
+++ /dev/null
@@ -1,98 +0,0 @@
1/*
2 * hugepage-shm:
3 *
4 * Example of using huge page memory in a user application using Sys V shared
5 * memory system calls. In this example the app is requesting 256MB of
6 * memory that is backed by huge pages. The application uses the flag
7 * SHM_HUGETLB in the shmget system call to inform the kernel that it is
8 * requesting huge pages.
9 *
10 * For the ia64 architecture, the Linux kernel reserves Region number 4 for
11 * huge pages. That means that if one requires a fixed address, a huge page
12 * aligned address starting with 0x800000... will be required. If a fixed
13 * address is not required, the kernel will select an address in the proper
14 * range.
15 * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
16 *
17 * Note: The default shared memory limit is quite low on many kernels,
18 * you may need to increase it via:
19 *
20 * echo 268435456 > /proc/sys/kernel/shmmax
21 *
22 * This will increase the maximum size per shared memory segment to 256MB.
23 * The other limit that you will hit eventually is shmall which is the
24 * total amount of shared memory in pages. To set it to 16GB on a system
25 * with a 4kB pagesize do:
26 *
27 * echo 4194304 > /proc/sys/kernel/shmall
28 */
29
30#include <stdlib.h>
31#include <stdio.h>
32#include <sys/types.h>
33#include <sys/ipc.h>
34#include <sys/shm.h>
35#include <sys/mman.h>
36
37#ifndef SHM_HUGETLB
38#define SHM_HUGETLB 04000
39#endif
40
41#define LENGTH (256UL*1024*1024)
42
43#define dprintf(x) printf(x)
44
45/* Only ia64 requires this */
46#ifdef __ia64__
47#define ADDR (void *)(0x8000000000000000UL)
48#define SHMAT_FLAGS (SHM_RND)
49#else
50#define ADDR (void *)(0x0UL)
51#define SHMAT_FLAGS (0)
52#endif
53
54int main(void)
55{
56 int shmid;
57 unsigned long i;
58 char *shmaddr;
59
60 if ((shmid = shmget(2, LENGTH,
61 SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W)) < 0) {
62 perror("shmget");
63 exit(1);
64 }
65 printf("shmid: 0x%x\n", shmid);
66
67 shmaddr = shmat(shmid, ADDR, SHMAT_FLAGS);
68 if (shmaddr == (char *)-1) {
69 perror("Shared memory attach failure");
70 shmctl(shmid, IPC_RMID, NULL);
71 exit(2);
72 }
73 printf("shmaddr: %p\n", shmaddr);
74
75 dprintf("Starting the writes:\n");
76 for (i = 0; i < LENGTH; i++) {
77 shmaddr[i] = (char)(i);
78 if (!(i % (1024 * 1024)))
79 dprintf(".");
80 }
81 dprintf("\n");
82
83 dprintf("Starting the Check...");
84 for (i = 0; i < LENGTH; i++)
85 if (shmaddr[i] != (char)i)
86 printf("\nIndex %lu mismatched\n", i);
87 dprintf("Done.\n");
88
89 if (shmdt((const void *)shmaddr) != 0) {
90 perror("Detach failure");
91 shmctl(shmid, IPC_RMID, NULL);
92 exit(3);
93 }
94
95 shmctl(shmid, IPC_RMID, NULL);
96
97 return 0;
98}
diff --git a/Documentation/vm/map_hugetlb.c b/Documentation/vm/map_hugetlb.c
deleted file mode 100644
index eda1a6d3578..00000000000
--- a/Documentation/vm/map_hugetlb.c
+++ /dev/null
@@ -1,77 +0,0 @@
1/*
2 * Example of using hugepage memory in a user application using the mmap
3 * system call with MAP_HUGETLB flag. Before running this program make
4 * sure the administrator has allocated enough default sized huge pages
5 * to cover the 256 MB allocation.
6 *
7 * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages.
8 * That means the addresses starting with 0x800000... will need to be
9 * specified. Specifying a fixed address is not required on ppc64, i386
10 * or x86_64.
11 */
12#include <stdlib.h>
13#include <stdio.h>
14#include <unistd.h>
15#include <sys/mman.h>
16#include <fcntl.h>
17
18#define LENGTH (256UL*1024*1024)
19#define PROTECTION (PROT_READ | PROT_WRITE)
20
21#ifndef MAP_HUGETLB
22#define MAP_HUGETLB 0x40000 /* arch specific */
23#endif
24
25/* Only ia64 requires this */
26#ifdef __ia64__
27#define ADDR (void *)(0x8000000000000000UL)
28#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
29#else
30#define ADDR (void *)(0x0UL)
31#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
32#endif
33
34static void check_bytes(char *addr)
35{
36 printf("First hex is %x\n", *((unsigned int *)addr));
37}
38
39static void write_bytes(char *addr)
40{
41 unsigned long i;
42
43 for (i = 0; i < LENGTH; i++)
44 *(addr + i) = (char)i;
45}
46
47static void read_bytes(char *addr)
48{
49 unsigned long i;
50
51 check_bytes(addr);
52 for (i = 0; i < LENGTH; i++)
53 if (*(addr + i) != (char)i) {
54 printf("Mismatch at %lu\n", i);
55 break;
56 }
57}
58
59int main(void)
60{
61 void *addr;
62
63 addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0);
64 if (addr == MAP_FAILED) {
65 perror("mmap");
66 exit(1);
67 }
68
69 printf("Returned address is %p\n", addr);
70 check_bytes(addr);
71 write_bytes(addr);
72 read_bytes(addr);
73
74 munmap(addr, LENGTH);
75
76 return 0;
77}
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