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_test 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_test script
b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition

Quoted 8 lines · On Sun, 5 Feb 2012 16:15:55 +0800 Dave Young <[email protected]> wrote:

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_test to do such work which will call the three test programs and check the return value of them.

Quoted 5 lines

Changes to original code including below:
a. add run_test script
b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition

I think Frederic is doing away with tools/testing/selftests/run_tests in favour of a Makefile target? ("make run_tests", for example).

Until we see such a patch we cannot finalise your patch and if I apply your patch, his patch will need more work. Not that this is rocket science ;)

tools/testing/selftests/vm/run_test

Quoted 6 lines

...

tools/testing/selftests/vm/run_test new file +0 -0

(We now have a "run_tests" and a "run_test". The difference in naming is irritating)

Your vm/run_test file does quite a lot of work and we couldn't sensibly move all its functionality into Makefile, I expect.

So I think it's OK to retain a script for this, but I do think that we should think up a standardized way of invoking it from vm/Makefile, so the top-level Makefile in tools/testing/selftests can simply do "cd vm;make run_test", where the run_test target exists in all subdirectories. The vm/Makefile run_test target can then call out to the script.

Also, please do not assume that the script has the x bit set. The x bit easily gets lost on kernel scripts (patch(1) can lose it) so it is safer to invoke the script via "/bin/sh script-name" or $SHELL or whatever.

Anyway, we should work with Frederic on sorting out some standard behavior before we can finalize this work, please.

Quoted 8 lines · On Sun, 5 Feb 2012 16:15:55 +0800 Dave Young <[email protected]> wrote:

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_test to do such work which will call the three test programs and check the return value of them.

Quoted 5 lines

Changes to original code including below:
a. add run_test script
b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition

I think Frederic is doing away with tools/testing/selftests/run_tests in favour of a Makefile target? ("make run_tests", for example).

Until we see such a patch we cannot finalise your patch and if I apply your patch, his patch will need more work. Not that this is rocket science ;)

tools/testing/selftests/vm/run_test

Quoted 5 lines

...

tools/testing/selftests/vm/run_test new file +0 -0

(We now have a "run_tests" and a "run_test". The difference in naming is irritating)

Your vm/run_test file does quite a lot of work and we couldn't sensibly move all its functionality into Makefile, I expect.

So I think it's OK to retain a script for this, but I do think that we should think up a standardized way of invoking it from vm/Makefile, so the top-level Makefile in tools/testing/selftests can simply do "cd vm;make run_test", where the run_test target exists in all subdirectories. The vm/Makefile run_test target can then call out to the script.

Also, please do not assume that the script has the x bit set. The x bit easily gets lost on kernel scripts (patch(1) can lose it) so it is safer to invoke the script via "/bin/sh script-name" or $SHELL or whatever.

Anyway, we should work with Frederic on sorting out some standard behavior before we can finalize this work, please.

Note that slub also has an embedded selftest (see function resiliency_test). That code could be separated out and put with the selftests that you are creating now.

I also have a series of in kernel benchmarks for the page allocation, vm statistics and slab allocators that could be useful to included somewhere.

All this code runs in the kernel context.

For the in kernel benchmarks I am creating modules that fail to load but first run the tests.

Drop the run_tests script and launch the selftests by calling "make run_tests" from the selftests top directory instead. This delegates to the Makefile on each selftest directory where it is decided how to launch the local test.

This drops the need to add each selftest directory on the now removed "run_tests" top script.

Quoted 7 lines · On Wed, 8 Feb 2012 04:40:59 +0100 Frederic Weisbecker <[email protected]>…

Drop the run_tests script and launch the selftests by calling "make run_tests" from the selftests top directory instead. This delegates to the Makefile on each selftest directory where it is decided how to launch the local test.

This drops the need to add each selftest directory on the now removed "run_tests" top script.

Looks good.

I did

cd tools/testing/selftests
make run_tests

and it didn't work. This?

From: Andrew Morton <[email protected]>
Subject: selftests/Makefile: make run_tests' depend on all'

So a "make run_tests" will build the tests before trying to run them.

Cc Frederic Weisbecker <[email protected]>

Signed-off-by Andrew Morton <[email protected]>

---

 tools/testing/selftests/Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN tools/testing/selftests/Makefile~a tools/testing/selftests/Makefile

Quoted 8 lines · On Sun, 5 Feb 2012 16:15:55 +0800 Dave Young <[email protected]> wrote:

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_test to do such work which will call the three test programs and check the return value of them.

Quoted 5 lines

Changes to original code including below:
a. add run_test script
b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition

I think Frederic is doing away with tools/testing/selftests/run_tests in favour of a Makefile target? ("make run_tests", for example).

Until we see such a patch we cannot finalise your patch and if I apply your patch, his patch will need more work. Not that this is rocket science ;)

tools/testing/selftests/vm/run_test

Quoted 5 lines

...

tools/testing/selftests/vm/run_test new file +0 -0

(We now have a "run_tests" and a "run_test". The difference in naming is irritating)

Your vm/run_test file does quite a lot of work and we couldn't sensibly move all its functionality into Makefile, I expect.

So I think it's OK to retain a script for this, but I do think that we should think up a standardized way of invoking it from vm/Makefile, so the top-level Makefile in tools/testing/selftests can simply do "cd vm;make run_test", where the run_test target exists in all subdirectories. The vm/Makefile run_test target can then call out to the script.

Also, please do not assume that the script has the x bit set. The x bit easily gets lost on kernel scripts (patch(1) can lose it) so it is safer to invoke the script via "/bin/sh script-name" or $SHELL or whatever.

Anyway, we should work with Frederic on sorting out some standard behavior before we can finalize this work, please.

Andrew, updated the patch as below, is it ok to you?
---

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

[v1 -> v2]:
1. [akpm:] rebased on runing make run_tests from Makefile
2. [akpm:] rename test script from run_test ro run_vmtests
2. fix a bug about shell exit code checking

Quoted 16 lines · On Thu, 9 Feb 2012 09:46:22 +0800 Dave Young <[email protected]> wrote:

Andrew, updated the patch as below, is it ok to you?
---

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

Quoted 5 lines

[v1 -> v2]:
1. [akpm:] rebased on runing make run_tests from Makefile
2. [akpm:] rename test script from run_test ro run_vmtests
2. fix a bug about shell exit code checking

So I tried to run this, from tools/testing/selftests.

a) The testing failed because ./vm's run_test target requires root.

We need to make a policy decision here. Do we require that selftests run as root? If not then the root-requiring selftests should warn and bail out without declaring a failure, so that those tests which can be run without root permissions can be successfully used.

b) When I ran the vm test, my machine went paralytically comatose for half a minute. That's a bit rude - if all the selftests do this then the selftests become kinda useless.

c) I can run "make run_tests" in the top-lvel directory and all is
well: the tools in ./vm get compiled first. But when I do "make clean ; cd vm ; make run-tests" it fails, because vm/Makefile doesn't build the targets before trying to run them.

This can be fixed with

tools/testing/selftests/vm/Makefile renamed from tools/testing/selftests/vm/Makefile~a +1 -1

@@ -7,7 +7,7 @@ all: hugepage-mmap hugepage-shm  map_hug
 %: %.c
 	$(CC) $(CFLAGS) -o $@ $^
 
-run_tests:
+run_tests: all
 	/bin/sh ./run_vmtests
 
 clean:

But this is unpleasing: a top-level "make run_tests" will end up trying to compile the targets twice.

We could change the top-level Makefile to a single-pass thing which just descends into the subdirectories and runs "make run_tests". But that gives us no way of compiling everything without also running everything. That's a huge PITA if running everything sends your machine comatose for half a minute!

So I think I'll go with the above patch.

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_test 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_test script
b. return error when read_bytes mismatch with writed bytes. c. coding style fixes: do not use assignment in if condition

Signed-off-by Dave Young <[email protected]>

---
 Documentation/vm/Makefile                          |    8 --
 tools/testing/selftests/Makefile                   |    2 +-
 tools/testing/selftests/run_tests                  |    6 +-
 tools/testing/selftests/vm/Makefile                |   11 +++
 .../testing/selftests}/vm/hugepage-mmap.c          |   13 ++--
 .../testing/selftests}/vm/hugepage-shm.c           |   10 ++-
 .../testing/selftests}/vm/map_hugetlb.c            |   10 ++-
 tools/testing/selftests/vm/run_test                |   77 ++++++++++++++++++++
 8 files changed, 112 insertions(+), 25 deletions(-)
 delete mode 100644 Documentation/vm/Makefile
 create mode 100644 tools/testing/selftests/vm/Makefile
 rename {Documentation => tools/testing/selftests}/vm/hugepage-mmap.c (93%)
 rename {Documentation => tools/testing/selftests}/vm/hugepage-shm.c (94%)
 rename {Documentation => tools/testing/selftests}/vm/map_hugetlb.c (94%)
 create mode 100755 tools/testing/selftests/vm/run_test

Documentation/vm/Makefile deleted +0 -8

deleted file mode 100644
index e538864..0000000
@@ -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)

tools/testing/selftests/Makefile +1 -1

index 4ec8401..9a72fe5 100644
@@ -1,4 +1,4 @@
-TARGETS = breakpoints
+TARGETS = breakpoints vm
 
 all:
 	for TARGET in $(TARGETS); do \

tools/testing/selftests/run_tests +4 -2

index 320718a..1f4a5ef 100644
@@ -1,8 +1,10 @@
 #!/bin/bash
 
-TARGETS=breakpoints
+TARGETS="breakpoints vm"
 
 for TARGET in $TARGETS
 do
-	$TARGET/run_test
+	cd "$TARGET"
+	./run_test
+	cd ..
 done

tools/testing/selftests/vm/Makefile new file +11 -0

new file mode 100644
index 0000000..537ec38
@@ -0,0 +1,11 @@
+# Makefile for vm selftests
+
+CC = $(CROSS_COMPILE)gcc
+CFLAGS = -Wall -Wextra
+
+all: hugepage-mmap hugepage-shm  map_hugetlb
+%: %.c
+	$(CC) $(CFLAGS) -o $@ $^
+
+clean:
+	$(RM) hugepage-mmap hugepage-shm  map_hugetlb

tools/testing/selftests/vm/hugepage-mmap.c renamed from Documentation/vm/hugepage-mmap.c +7 -6

similarity index 93%
rename from Documentation/vm/hugepage-mmap.c
rename to tools/testing/selftests/vm/hugepage-mmap.c
index db0dd9a..a10f310 100644
@@ -22,7 +22,7 @@
 #include <sys/mman.h>
 #include <fcntl.h>
 
-#define FILE_NAME "/mnt/hugepagefile"
+#define FILE_NAME "huge/hugepagefile"
 #define LENGTH (256UL*1024*1024)
 #define PROTECTION (PROT_READ | PROT_WRITE)
 

@@ -48,7 +48,7 @@ static void write_bytes(char *addr)
 		*(addr + i) = (char)i;
 }
 
-static void read_bytes(char *addr)
+static int read_bytes(char *addr)
 {
 	unsigned long i;
 

@@ -56,14 +56,15 @@ static void read_bytes(char *addr)
 	for (i = 0; i < LENGTH; i++)
 		if (*(addr + i) != (char)i) {
 			printf("Mismatch at %lu\n", i);
-			break;
+			return 1;
 		}
+	return 0;
 }
 
 int main(void)
 {
 	void *addr;
-	int fd;
+	int fd, ret;
 
 	fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755);
 	if (fd < 0) {

@@ -81,11 +82,11 @@ int main(void)
 	printf("Returned address is %p\n", addr);
 	check_bytes(addr);
 	write_bytes(addr);
-	read_bytes(addr);
+	ret = read_bytes(addr);
 
 	munmap(addr, LENGTH);
 	close(fd);
 	unlink(FILE_NAME);
 
-	return 0;
+	return ret;
 }

tools/testing/selftests/vm/hugepage-shm.c renamed from Documentation/vm/hugepage-shm.c +6 -4

similarity index 94%
rename from Documentation/vm/hugepage-shm.c
rename to tools/testing/selftests/vm/hugepage-shm.c
index 07956d8..0d0ef4f 100644
@@ -57,8 +57,8 @@ int main(void)
 	unsigned long i;
 	char *shmaddr;
 
-	if ((shmid = shmget(2, LENGTH,
-			    SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W)) < 0) {
+	shmid = shmget(2, LENGTH, SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+	if (shmid < 0) {
 		perror("shmget");
 		exit(1);
 	}

@@ -82,14 +82,16 @@ int main(void)
 
 	dprintf("Starting the Check...");
 	for (i = 0; i < LENGTH; i++)
-		if (shmaddr[i] != (char)i)
+		if (shmaddr[i] != (char)i) {
 			printf("\nIndex %lu mismatched\n", i);
+			exit(3);
+		}
 	dprintf("Done.\n");
 
 	if (shmdt((const void *)shmaddr) != 0) {
 		perror("Detach failure");
 		shmctl(shmid, IPC_RMID, NULL);
-		exit(3);
+		exit(4);
 	}
 
 	shmctl(shmid, IPC_RMID, NULL);

tools/testing/selftests/vm/map_hugetlb.c renamed from Documentation/vm/map_hugetlb.c +6 -4

similarity index 94%
rename from Documentation/vm/map_hugetlb.c
rename to tools/testing/selftests/vm/map_hugetlb.c
index eda1a6d..ac56639 100644
@@ -44,7 +44,7 @@ static void write_bytes(char *addr)
 		*(addr + i) = (char)i;
 }
 
-static void read_bytes(char *addr)
+static int read_bytes(char *addr)
 {
 	unsigned long i;
 

@@ -52,13 +52,15 @@ static void read_bytes(char *addr)
 	for (i = 0; i < LENGTH; i++)
 		if (*(addr + i) != (char)i) {
 			printf("Mismatch at %lu\n", i);
-			break;
+			return 1;
 		}
+	return 0;
 }
 
 int main(void)
 {
 	void *addr;
+	int ret;
 
 	addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0);
 	if (addr == MAP_FAILED) {

@@ -69,9 +71,9 @@ int main(void)
 	printf("Returned address is %p\n", addr);
 	check_bytes(addr);
 	write_bytes(addr);
-	read_bytes(addr);
+	ret = read_bytes(addr);
 
 	munmap(addr, LENGTH);
 
-	return 0;
+	return ret;
 }

tools/testing/selftests/vm/run_test new file +48 -0

new file mode 100755
index 0000000..33d355d
@@ -0,0 +1,77 @@
+#!/bin/bash
+#please run as root
+
+#we need 256M, below is the size in kB
+needmem=262144
+mnt=./huge
+
+#get pagesize and freepages from /proc/meminfo
+while read name size unit; do
+	if [ "$name" = "HugePages_Free:" ]; then
+		freepgs=$size
+	fi
+	if [ "$name" = "Hugepagesize:" ]; then
+		pgsize=$size
+	fi
+done < /proc/meminfo
+
+#set proper nr_hugepages
+if [ -n "$freepgs" ] && [ -n "$pgsize" ]; then
+	nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
+	needpgs=`expr $needmem / $pgsize`
+	if [ $freepgs -lt $needpgs ]; then
+		lackpgs=$(( $needpgs - $freepgs ))
+		echo $(( $lackpgs + $nr_hugepgs )) > /proc/sys/vm/nr_hugepages
+		if [ $? -ne 0 ]; then
+			echo "Please run this test as root"
+			exit 1
+		fi
+	fi
+else
+	echo "no hugetlbfs support in kernel?"
+	exit 1
+fi
+
+mkdir $mnt
+mount -t hugetlbfs none $mnt
+
+echo "--------------------"
+echo "runing hugepage-mmap"
+echo "--------------------"
+./hugepage-mmap
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+else
+	echo "[PASS]"
+fi
+
+shmmax=`cat /proc/sys/kernel/shmmax`

tools/testing/selftests/vm/run_test new file +19 -0

+	echo "[FAIL]"
+else
+	echo "[PASS]"
+fi
+
+echo "--------------------"
+echo "runing map_hugetlb"
+echo "--------------------"
+./map_hugetlb
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+else
+	echo "[PASS]"
+fi
+
+#cleanup
+umount $mnt
+rm -rf $mnt
+echo $nr_hugepgs > /proc/sys/vm/nr_hugepages