Re: [RFC v4 9/9] kmsg: selftests

[Shuah Khan <shuahkh@osg.samsung.com>]

On 10/19/2015 10:50 AM, Paul Osmialowski wrote:
> This patch adds selftests framework and four test scenarios for kmsg.
> 
> The framework shape and code was inspired by similar selftests framework
> for kdbus.
> 
> Signed-off-by: Paul Osmialowski <p.osmialowsk@samsung.com>
> ---
>  samples/kmsg/kmsg-api.h                            |  44 +++
>  tools/testing/selftests/Makefile                   |   1 +
>  tools/testing/selftests/kmsg/.gitignore            |   1 +
>  tools/testing/selftests/kmsg/Makefile              |  30 ++
>  tools/testing/selftests/kmsg/kmsg-test.c           | 329 +++++++++++++++++++++
>  tools/testing/selftests/kmsg/kmsg-test.h           |  34 +++
>  tools/testing/selftests/kmsg/test-buffer-add-del.c |  76 +++++
>  .../kmsg/test-buffer-add-write-read-del.c          | 161 ++++++++++
>  .../kmsg/test-buffer-buf-multithreaded-torture.c   | 199 +++++++++++++
>  .../selftests/kmsg/test-buffer-buf-torture.c       | 139 +++++++++
>  10 files changed, 1014 insertions(+)
>  create mode 100644 samples/kmsg/kmsg-api.h
>  create mode 100644 tools/testing/selftests/kmsg/.gitignore
>  create mode 100644 tools/testing/selftests/kmsg/Makefile
>  create mode 100644 tools/testing/selftests/kmsg/kmsg-test.c
>  create mode 100644 tools/testing/selftests/kmsg/kmsg-test.h
>  create mode 100644 tools/testing/selftests/kmsg/test-buffer-add-del.c
>  create mode 100644 tools/testing/selftests/kmsg/test-buffer-add-write-read-del.c
>  create mode 100644 tools/testing/selftests/kmsg/test-buffer-buf-multithreaded-torture.c
>  create mode 100644 tools/testing/selftests/kmsg/test-buffer-buf-torture.c
> 
> diff --git a/samples/kmsg/kmsg-api.h b/samples/kmsg/kmsg-api.h
> new file mode 100644
> index 0000000..9004acd
> --- /dev/null
> +++ b/samples/kmsg/kmsg-api.h
> @@ -0,0 +1,44 @@
> +#ifndef KMSG_API_H
> +#define KMSG_API_H
> +
> +#include <stdint.h>
> +#include <errno.h>
> +#include <sys/ioctl.h>
> +#include <linux/kmsg_ioctl.h>
> +
> +static inline int kmsg_cmd_buffer_add(int fd, struct kmsg_cmd_buffer_add *cmd)
> +{
> +	int ret = ioctl(fd, KMSG_CMD_BUFFER_ADD, cmd);
> +
> +	return (ret < 0) ? (errno > 0 ? -errno : -EINVAL) : 0;
> +}
> +
> +static inline int kmsg_cmd_buffer_del(int fd, int *minor)
> +{
> +	int ret = ioctl(fd, KMSG_CMD_BUFFER_DEL, minor);
> +
> +	return (ret < 0) ? (errno > 0 ? -errno : -EINVAL) : 0;
> +}
> +
> +static inline int kmsg_cmd_get_buf_size(int fd, uint32_t *size)
> +{
> +	int ret = ioctl(fd, KMSG_CMD_GET_BUF_SIZE, size);
> +
> +	return (ret < 0) ? (errno > 0 ? -errno : -EINVAL) : 0;
> +}
> +
> +static inline int kmsg_cmd_get_read_size_max(int fd, uint32_t *max_size)
> +{
> +	int ret = ioctl(fd, KMSG_CMD_GET_READ_SIZE_MAX, max_size);
> +
> +	return (ret < 0) ? (errno > 0 ? -errno : -EINVAL) : 0;
> +}
> +
> +static inline int kmsg_cmd_clear(int fd)
> +{
> +	int ret = ioctl(fd, KMSG_CMD_CLEAR);
> +
> +	return (ret < 0) ? (errno > 0 ? -errno : -EINVAL) : 0;
> +}
> +
> +#endif /* KMSG_API_H */
> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
> index bf4ece6..b7bdf58 100644
> --- a/tools/testing/selftests/Makefile
> +++ b/tools/testing/selftests/Makefile
> @@ -7,6 +7,7 @@ TARGETS += ftrace
>  TARGETS += futex
>  TARGETS += kcmp
>  TARGETS += kdbus

Doesn't look like this patch is based on linux-kselftest next
or Linus's latest. Please base your work on either one of the
above. Please make sure "make kselftest" from top level Makefile
doesn't break.

> +TARGETS += kmsg
>  TARGETS += lib
>  TARGETS += membarrier
>  TARGETS += memfd
> diff --git a/tools/testing/selftests/kmsg/.gitignore b/tools/testing/selftests/kmsg/.gitignore
> new file mode 100644
> index 0000000..687d517
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/.gitignore
> @@ -0,0 +1 @@
> +kmsg-test
> diff --git a/tools/testing/selftests/kmsg/Makefile b/tools/testing/selftests/kmsg/Makefile
> new file mode 100644
> index 0000000..b4ba892
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/Makefile
> @@ -0,0 +1,30 @@
> +CFLAGS += -I../../../../usr/include/
> +CFLAGS += -I../../../../samples/kmsg/
> +CFLAGS += -I../../../../include/uapi/
> +CFLAGS += -std=gnu99 -Wall
> +CFLAGS += -DKBUILD_MODNAME=\"kmsg\" -D_GNU_SOURCE
> +CFLAGS += -pthread
> +LDLIBS += -pthread
> +
> +OBJS= \
> +	kmsg-test.o				\
> +	test-buffer-add-del.o			\
> +	test-buffer-add-write-read-del.o	\
> +	test-buffer-buf-torture.o		\
> +	test-buffer-buf-multithreaded-torture.o
> +
> +all: kmsg-test
> +
> +include ../lib.mk
> +
> +%.o: %.c kmsg-test.h
> +	$(CC) $(CFLAGS) -c $< -o $@
> +
> +kmsg-test: $(OBJS)
> +	$(CC) $(CFLAGS) $^ $(LDLIBS) -o $@
> +
> +run_tests:
> +	./kmsg-test --tap

What does --tap do? Is this a longform option?
I don't see it in usage()

> +
> +clean:
> +	rm -f *.o kmsg-test
> diff --git a/tools/testing/selftests/kmsg/kmsg-test.c b/tools/testing/selftests/kmsg/kmsg-test.c
> new file mode 100644
> index 0000000..4f17b73
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/kmsg-test.c
> @@ -0,0 +1,329 @@
> +#include <stddef.h>
> +#include <stdbool.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <time.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <getopt.h>
> +#include <sys/types.h>
> +#include <sys/wait.h>
> +#include <sys/stat.h>
> +
> +#include "kmsg-test.h"
> +
> +struct kmsg_test {
> +	const char	*name;
> +	const char	*desc;
> +	int (*func)(const struct kmsg_test_args *args);
> +};
> +
> +static const struct kmsg_test tests[] = {
> +	{
> +		.name	= "buffer-add-del",
> +		.desc	= "create and delete kmsg devices",
> +		.func	= kmsg_test_buffer_add_del,
> +	}, {
> +		.name	= "buffer-add-write-read-del",
> +		.desc	= "create w/r and del kmsg device",
> +		.func	= kmsg_test_buffer_add_write_read_del,
> +	}, {
> +		.name	= "buffer-buf-torture",
> +		.desc	= "fill more than whole buffer can hold",
> +		.func	= kmsg_test_buffer_buf_torture,
> +	}, {
> +		.name	= "buffer-buf-multitheaded-torture",
> +		.desc	= "fill from many threads",
> +		.func	= kmsg_test_buffer_buf_multithreaded_torture,
> +	},
> +};
> +
> +#define N_TESTS ARRAY_SIZE(tests)
> +
> +FILE *kmsg_get_device(int minor, const char *mode)
> +{
> +	char path[80] = "";
> +	dev_t dev = makedev(1, minor);
> +
> +	if (minor < 0) {
> +		printf("Invalid minor number %d\n", minor);
> +		return NULL;
> +	}
> +
> +	snprintf(path, sizeof(path), "/tmp/kmsg-%d", minor);
> +
> +	if (access(path, F_OK) < 0) {
> +		if (mknod(path, S_IFCHR | 0600, dev)) {
> +			printf("Cannot create device %s with minor %d\n",
> +								path, minor);
> +			return NULL;
> +		}
> +	}
> +
> +	if (access(path, F_OK) < 0) {
> +		printf("Cannot access device %s\n", path);
> +		return NULL;
> +	}
> +
> +	return fopen(path, mode);
> +}
> +
> +int kmsg_drop_device(int minor)
> +{
> +	char path[80] = "";
> +
> +	if (minor < 0) {
> +		printf("Invalid minor number %d\n", minor);
> +		return -1;
> +	}
> +
> +	snprintf(path, sizeof(path), "/tmp/kmsg-%d", minor);
> +
> +	return unlink(path);
> +}
> +
> +static void usage(const char *argv0)
> +{
> +	unsigned int i, j;
> +
> +	printf("Usage: %s [options]\n"
> +	       "Options:\n"
> +	       "\t-x, --loop		Run in a loop\n"
> +	       "\t-f, --fork		Fork before running a test\n"
> +	       "\t-h, --help		Print this help\n"
> +	       "\t-t, --test <test-id>	Run one specific test only\n"
> +	       "\t-w, --wait <secs>	Wait <secs> before actually starting test\n"
> +	       "\n", argv0);
> +
> +	printf("By default, all test are run once, and a summary is printed.\n"
> +	       "Available tests for --test:\n\n");
> +
> +	for (i = 0; i < N_TESTS; i++) {
> +		const struct kmsg_test *t = tests + i;
> +
> +		printf("\t%s", t->name);
> +
> +		for (j = 0; j < 24 - strlen(t->name); j++)
> +			printf(" ");
> +
> +		printf("Test %s\n", t->desc);
> +	}
> +
> +	printf("\n");
> +	printf("Note that some tests may, if run specifically by --test, ");
> +	printf("behave differently, and not terminate by themselves.\n");
> +
> +	exit(EXIT_FAILURE);
> +}
> +
> +static void print_test_result(int ret)
> +{
> +	switch (ret) {
> +	case TEST_OK:
> +		printf("OK");
> +		break;
> +	case TEST_SKIP:
> +		printf("SKIPPED");
> +		break;
> +	case TEST_ERR:
> +		printf("ERROR");
> +		break;
> +	}
> +}
> +
> +static int test_run(const struct kmsg_test *t,
> +		    const struct kmsg_test_args *kmsg_args,
> +		    int wait)
> +{
> +	int ret;
> +
> +	if (wait > 0) {
> +		printf("Sleeping %d seconds before running test ...\n", wait);
> +		sleep(wait);
> +	}
> +
> +	ret = t->func(kmsg_args);
> +	return ret;
> +}
> +
> +static int test_run_forked(const struct kmsg_test *t,
> +			   const struct kmsg_test_args *kmsg_args,
> +			   int wait)
> +{
> +	int ret;
> +	pid_t pid;
> +
> +	pid = fork();
> +	if (pid < 0) {
> +		return TEST_ERR;
> +	} else if (pid == 0) {
> +		ret = test_run(t, kmsg_args, wait);
> +		_exit(ret);
> +	}
> +
> +	pid = waitpid(pid, &ret, 0);
> +	if (pid <= 0)
> +		return TEST_ERR;
> +	else if (!WIFEXITED(ret))
> +		return TEST_ERR;
> +	else
> +		return WEXITSTATUS(ret);
> +}
> +
> +static int start_all_tests(const struct kmsg_test_args *kmsg_args)
> +{
> +	int ret;
> +	unsigned int fail_cnt = 0;
> +	unsigned int skip_cnt = 0;
> +	unsigned int ok_cnt = 0;
> +	unsigned int i, n;
> +	const struct kmsg_test *t;
> +
> +	for (i = 0; i < N_TESTS; i++) {
> +		t = tests + i;
> +
> +		printf("Testing %s (%s) ", t->desc, t->name);
> +		for (n = 0; n < 60 - strlen(t->desc) - strlen(t->name); n++)
> +			printf(".");
> +		printf(" ");
> +
> +		ret = test_run_forked(t, kmsg_args, 0);
> +		switch (ret) {
> +		case TEST_OK:
> +			ok_cnt++;
> +			break;
> +		case TEST_SKIP:
> +			skip_cnt++;
> +			break;
> +		case TEST_ERR:
> +			fail_cnt++;
> +			break;
> +		}
> +
> +		print_test_result(ret);
> +		printf("\n");
> +	}
> +
> +	printf("\nSUMMARY: %u tests passed, %u skipped, %u failed\n",
> +					    ok_cnt, skip_cnt, fail_cnt);
> +
> +	return fail_cnt > 0 ? TEST_ERR : TEST_OK;
> +}
> +
> +static int start_one_test(const struct kmsg_test_args *kmsg_args)
> +{
> +	int i, ret;
> +	bool test_found = false;
> +	const struct kmsg_test *t;
> +
> +	for (i = 0; i < N_TESTS; i++) {
> +		t = tests + i;
> +
> +		if (strcmp(t->name, kmsg_args->test))
> +			continue;
> +
> +		do {
> +			test_found = true;
> +			if (kmsg_args->fork)
> +				ret = test_run_forked(t, kmsg_args,
> +						      kmsg_args->wait);
> +			else
> +				ret = test_run(t, kmsg_args,
> +					       kmsg_args->wait);
> +
> +			printf("Testing %s: ", t->desc);
> +			print_test_result(ret);
> +			printf("\n");
> +
> +			if (ret != TEST_OK)
> +				break;
> +		} while (kmsg_args->loop);
> +
> +		return ret;
> +	}
> +
> +	if (!test_found) {
> +		printf("Unknown test-id '%s'\n", kmsg_args->test);
> +		return TEST_ERR;
> +	}
> +
> +	return TEST_OK;
> +}
> +
> +static int start_tests(const struct kmsg_test_args *kmsg_args)
> +{
> +	int ret = 0;
> +
> +	if (kmsg_args->test) {
> +		ret = start_one_test(kmsg_args);
> +	} else  {
> +		do {
> +			ret = start_all_tests(kmsg_args);
> +			if (ret != TEST_OK)
> +				break;
> +		} while (kmsg_args->loop);
> +	}
> +
> +	return ret;
> +}
> +
> +int main(int argc, char *argv[])
> +{
> +	int t, ret = 0;
> +	struct kmsg_test_args *kmsg_args;
> +	char *exec = basename(argv[0]);
> +
> +	kmsg_args = malloc(sizeof(*kmsg_args));
> +	if (!kmsg_args) {
> +		printf("unable to malloc() kmsg_args\n");
> +		return EXIT_FAILURE;
> +	}
> +
> +	memset(kmsg_args, 0, sizeof(*kmsg_args));
> +
> +	static const struct option options[] = {
> +		{ "loop",	no_argument,		NULL, 'x' },
> +		{ "help",	no_argument,		NULL, 'h' },
> +		{ "test",	required_argument,	NULL, 't' },
> +		{ "wait",	required_argument,	NULL, 'w' },
> +		{ "fork",	no_argument,		NULL, 'f' },
> +		{}
> +	};
> +
> +	if (strcmp(exec, "kmsg-test") != 0)
> +		kmsg_args->test = exec;
> +
> +	while ((t = getopt_long(argc, argv, "hxfm:r:t:b:w:a",
> +						options, NULL)) >= 0) {
> +		switch (t) {
> +		case 'x':
> +			kmsg_args->loop = 1;
> +			break;
> +
> +		case 't':
> +			kmsg_args->test = optarg;
> +			break;
> +
> +		case 'w':
> +			kmsg_args->wait = strtol(optarg, NULL, 10);
> +			break;
> +
> +		case 'f':
> +			kmsg_args->fork = 1;
> +			break;
> +
> +		default:
> +		case 'h':
> +			usage(argv[0]);
> +		}
> +	}
> +
> +	ret = start_tests(kmsg_args);
> +	if (ret == TEST_ERR)
> +		return EXIT_FAILURE;
> +
> +	free(kmsg_args);
> +
> +	return 0;
> +}
> diff --git a/tools/testing/selftests/kmsg/kmsg-test.h b/tools/testing/selftests/kmsg/kmsg-test.h
> new file mode 100644
> index 0000000..b9ce896
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/kmsg-test.h
> @@ -0,0 +1,34 @@
> +#ifndef _KMSG_TEST_H_
> +#define _KMSG_TEST_H_
> +
> +#include <stdio.h>
> +
> +#define DEV_KMSG "/dev/kmsg"
> +
> +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
> +
> +#define KMSG_REQUESTED_BUF_SIZE (1024 * 256)
> +
> +enum {
> +	TEST_OK,
> +	TEST_SKIP,
> +	TEST_ERR,
> +};
> +
> +struct kmsg_test_args {
> +	int loop;
> +	int wait;
> +	int fork;
> +	const char *test;
> +};
> +
> +FILE *kmsg_get_device(int minor, const char *mode);
> +int kmsg_drop_device(int minor);
> +
> +int kmsg_test_buffer_add_del(const struct kmsg_test_args *args);
> +int kmsg_test_buffer_add_write_read_del(const struct kmsg_test_args *args);
> +int kmsg_test_buffer_buf_torture(const struct kmsg_test_args *args);
> +int kmsg_test_buffer_buf_multithreaded_torture(
> +					const struct kmsg_test_args *args);
> +
> +#endif /* _KMSG_TEST_H_ */
> diff --git a/tools/testing/selftests/kmsg/test-buffer-add-del.c b/tools/testing/selftests/kmsg/test-buffer-add-del.c
> new file mode 100644
> index 0000000..22b69ac
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/test-buffer-add-del.c
> @@ -0,0 +1,76 @@
> +#include <stddef.h>
> +#include <stdint.h>
> +#include <stdio.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <kmsg-api.h>
> +
> +#include "kmsg-test.h"
> +
> +int kmsg_test_buffer_add_del(const struct kmsg_test_args *args)
> +{
> +	int i;
> +	int fd = open(DEV_KMSG, O_RDWR);
> +	struct kmsg_cmd_buffer_add cmd = { 0 };
> +	int minors[] = { -1, -1, -1, -1 };
> +	FILE *fds[ARRAY_SIZE(minors)];
> +	int retval = TEST_OK;
> +	uint32_t size;
> +
> +	if (fd < 0) {
> +		printf("Failed: cannot open %s\n", DEV_KMSG);
> +		return TEST_ERR;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		fds[i] = NULL;
> +		cmd.size = KMSG_REQUESTED_BUF_SIZE;
> +		cmd.mode = 0662;
> +		if (kmsg_cmd_buffer_add(fd, &cmd)) {
> +			printf("Failed to add buffer\n");
> +			goto error;
> +		}
> +		if (cmd.minor < 0) {
> +			printf("Minor number < 0\n");
> +			goto error;
> +		}
> +		minors[i] = cmd.minor;
> +		fds[i] = kmsg_get_device(minors[i], "r");
> +		if (!fds[i]) {
> +			printf("Cannot get device %d\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(fds[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +	}
> +
> +	goto cleanup;
> +
> +error:
> +	retval = TEST_ERR;
> +
> +cleanup:
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		if (minors[i] < 0)
> +			continue;
> +		if (fds[i])
> +			fclose(fds[i]);
> +		if (kmsg_drop_device(minors[i])) {
> +			printf("Failed to delete device file %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +		if (kmsg_cmd_buffer_del(fd, &minors[i])) {
> +			printf("Failed to delete buffer %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +	}
> +	close(fd);
> +	return retval;
> +}
> diff --git a/tools/testing/selftests/kmsg/test-buffer-add-write-read-del.c b/tools/testing/selftests/kmsg/test-buffer-add-write-read-del.c
> new file mode 100644
> index 0000000..ab4223f
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/test-buffer-add-write-read-del.c
> @@ -0,0 +1,161 @@
> +#include <stddef.h>
> +#include <stdint.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <kmsg-api.h>
> +
> +#include "kmsg-test.h"
> +
> +static const char *message(char *buff, size_t size, int i, int j)
> +{
> +	snprintf(buff, size, "Test message (%d, %d)", i, j);
> +	return buff;
> +}
> +
> +int kmsg_test_buffer_add_write_read_del(const struct kmsg_test_args *args)
> +{
> +	int i, j;
> +	int fd = open(DEV_KMSG, O_RDWR);
> +	struct kmsg_cmd_buffer_add cmd = { 0 };
> +	int minors[] = { -1, -1, -1, -1 };
> +	FILE *fds[ARRAY_SIZE(minors)];
> +	FILE *log[ARRAY_SIZE(minors)];
> +	int logfd;
> +	int retval = TEST_OK;
> +	uint32_t size;
> +	char txt[80] = "";
> +	char *buff = NULL;
> +	const char *msg;
> +	char *msgend;
> +
> +	if (fd < 0) {
> +		printf("Failed: cannot open %s\n", DEV_KMSG);
> +		return TEST_ERR;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		fds[i] = NULL;
> +		log[i] = NULL;
> +		cmd.size = KMSG_REQUESTED_BUF_SIZE;
> +		cmd.mode = 0662;
> +		if (kmsg_cmd_buffer_add(fd, &cmd)) {
> +			printf("Failed to add buffer\n");
> +			goto error;
> +		}
> +		if (cmd.minor < 0) {
> +			printf("Minor number < 0\n");
> +			goto error;
> +		}
> +		minors[i] = cmd.minor;
> +
> +		fds[i] = kmsg_get_device(minors[i], "w");
> +		if (!fds[i]) {
> +			printf("Cannot get device %d for write\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(fds[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +		log[i] = kmsg_get_device(minors[i], "r");
> +		if (!log[i]) {
> +			printf("Cannot get device %d for read\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(log[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +
> +		for (j = 0; j <= i; j++) {
> +			if (kmsg_cmd_clear(fileno(fds[j]))) {
> +				printf("Cannot clear buffer on device %d\n", j);
> +				goto error;
> +			}
> +			fprintf(fds[j], "%s\n", message(txt, ARRAY_SIZE(txt),
> +									i, j));
> +			fflush(fds[j]);
> +		}
> +
> +		for (j = 0; j <= i; j++) {
> +			logfd = fileno(log[j]);
> +			size = 0;
> +			if (kmsg_cmd_get_read_size_max(logfd, &size)) {
> +				printf("Cannot get buf size on device %d\n", j);
> +				goto error;
> +			}
> +			if (!size) {
> +				printf("Expected non-zero buf size on %d\n", j);
> +				goto error;
> +			}
> +			buff = malloc(size);
> +			if (!buff) {
> +				printf("Out of memory\n");
> +				goto error;
> +			}
> +			if (read(logfd, buff, size) <= 0) {
> +				printf("Could not read from buffer %d\n", j);
> +				goto error;
> +			}
> +			msg = strchr(buff, ';');
> +			msgend = strchr(buff, '\n');
> +			if ((!msg) || (!msgend)) {
> +				printf("Could not read stored log on %d\n", j);
> +				goto error;
> +			}
> +			msg++;
> +			*msgend = 0;
> +			if (strcmp(msg, message(txt, ARRAY_SIZE(txt), i, j))) {
> +				printf("Messages do not match on %d\n", j);
> +				goto error;
> +			}
> +			free(buff);
> +			buff = NULL;
> +		}
> +	}
> +
> +	goto cleanup;
> +
> +error:
> +	retval = TEST_ERR;
> +
> +cleanup:
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		if (minors[i] < 0)
> +			continue;
> +		if (fds[i])
> +			fclose(fds[i]);
> +		if (log[i]) {
> +			if (kmsg_cmd_clear(fileno(log[i]))) {
> +				printf("Failed to clear device %d\n", i);
> +				retval = TEST_ERR;
> +			}
> +			fclose(log[i]);
> +		}
> +		if (kmsg_drop_device(minors[i])) {
> +			printf("Failed to delete device file %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +		if (kmsg_cmd_buffer_del(fd, &minors[i])) {
> +			printf("Failed to delete buffer %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +	}
> +	close(fd);
> +	if (buff)
> +		free(buff);
> +	return retval;
> +}
> diff --git a/tools/testing/selftests/kmsg/test-buffer-buf-multithreaded-torture.c b/tools/testing/selftests/kmsg/test-buffer-buf-multithreaded-torture.c
> new file mode 100644
> index 0000000..5510b13
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/test-buffer-buf-multithreaded-torture.c
> @@ -0,0 +1,199 @@
> +#include <stddef.h>
> +#include <stdbool.h>
> +#include <stdint.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <pthread.h>
> +#include <kmsg-api.h>
> +
> +#include "kmsg-test.h"
> +
> +#define SOME_BUFF_SIZE 4096
> +#define THREADS_PER_DEVICE 10
> +
> +static bool ok = true;
> +static bool nok = !true;
> +
> +static void *kmsg_test_thread_func(void *data)
> +{
> +	char buff[SOME_BUFF_SIZE];
> +	int minor = *((int *)data);
> +	FILE *f = kmsg_get_device(minor, "w");
> +	int fd;
> +	void *retval = &ok;
> +	int iter;
> +	ssize_t s;
> +	uint32_t size, done;
> +	uint32_t max_size;
> +
> +	memset(buff, 'A', ARRAY_SIZE(buff));
> +	buff[ARRAY_SIZE(buff) - 1] = 0;
> +
> +	if (!f) {
> +		printf("Cannot get device for write\n");
> +		return &nok;
> +	}
> +	fd = fileno(f);
> +
> +	size = 0;
> +	if (kmsg_cmd_get_buf_size(fd, &size)) {
> +		printf("Cannot get buf size\n");
> +		goto error;
> +	}
> +	if (size != KMSG_REQUESTED_BUF_SIZE) {
> +		printf("Invalid buf size\n");
> +		goto error;
> +	}
> +
> +	if (kmsg_cmd_clear(fd)) {
> +		printf("Cannot clear buffer\n");
> +		goto error;
> +	}
> +
> +	iter = 0;
> +	while (done < (KMSG_REQUESTED_BUF_SIZE * 2)) {
> +		s = write(fd, buff, ARRAY_SIZE(buff));
> +		if (s < 0) {
> +			printf("Cannot write iteration %d\n", iter);
> +			goto error;
> +		}
> +		done += s;
> +
> +		max_size = 0;
> +		if (kmsg_cmd_get_read_size_max(fd, &max_size)) {
> +			printf("Cannot get max_size\n");
> +			goto error;
> +		}
> +		if (!max_size) {
> +			printf("Expected non-zero max_size\n");
> +			goto error;
> +		}
> +
> +		iter++;
> +	}
> +
> +	goto cleanup;
> +
> +error:
> +	retval = &nok;
> +
> +cleanup:
> +	fclose(f);
> +
> +	return retval;
> +}
> +
> +int kmsg_test_buffer_buf_multithreaded_torture(
> +					const struct kmsg_test_args *args)
> +{
> +	int i, j;
> +	int fd = open(DEV_KMSG, O_RDWR);
> +	struct kmsg_cmd_buffer_add cmd = { 0 };
> +	int minors[] = { -1, -1, -1, -1 };
> +	FILE *log[ARRAY_SIZE(minors)];
> +	int retval = TEST_OK;
> +	pthread_t threads[ARRAY_SIZE(minors)][THREADS_PER_DEVICE];
> +	bool started[ARRAY_SIZE(minors)][THREADS_PER_DEVICE];
> +	uint32_t size;
> +	uint32_t max_size;
> +	void *retptr;
> +
> +	for (i = 0; i < ARRAY_SIZE(minors); i++)
> +		for (j = 0; j < THREADS_PER_DEVICE; j++)
> +			started[i][j] = false;
> +
> +	if (fd < 0) {
> +		printf("Failed: cannot open %s\n", DEV_KMSG);
> +		return TEST_ERR;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		log[i] = NULL;
> +		cmd.size = KMSG_REQUESTED_BUF_SIZE;
> +		cmd.mode = 0662;
> +		if (kmsg_cmd_buffer_add(fd, &cmd)) {
> +			printf("Failed to add buffer\n");
> +			goto error;
> +		}
> +		if (cmd.minor < 0) {
> +			printf("Minor number < 0\n");
> +			goto error;
> +		}
> +		minors[i] = cmd.minor;
> +
> +		log[i] = kmsg_get_device(minors[i], "r");
> +		if (!log[i]) {
> +			printf("Cannot get device %d for read\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(log[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +
> +		for (j = 0; j < THREADS_PER_DEVICE; j++) {
> +			if (pthread_create(&threads[i][j], NULL,
> +					  kmsg_test_thread_func, &minors[i])) {
> +				printf("Cannot create thread %d for dev %d\n",
> +									j, i);
> +				goto error;
> +			}
> +			started[i][j] = true;
> +		}
> +	}
> +
> +	goto cleanup;
> +
> +error:
> +	retval = TEST_ERR;
> +
> +cleanup:
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		for (j = 0; j < THREADS_PER_DEVICE; j++)
> +			if (started[i][j]) {
> +				if (pthread_join(threads[i][j], &retptr)) {
> +					printf("pthread_join() failed %d:%d\n",
> +									i, j);
> +					retval = TEST_ERR;
> +				}
> +				if (!(*((bool *)retptr)))
> +					retval = TEST_ERR;
> +			}
> +		if (minors[i] < 0)
> +			continue;
> +		if (log[i]) {
> +			max_size = 0;
> +			if (kmsg_cmd_get_read_size_max(fileno(log[i]),
> +								&max_size)) {
> +				printf("Cannot get max_size\n");
> +				retval = TEST_ERR;
> +			}
> +			if (!max_size) {
> +				printf("Expected non-zero max_size\n");
> +				retval = TEST_ERR;
> +			}
> +			if (kmsg_cmd_clear(fileno(log[i]))) {
> +				printf("Failed to clear device %d\n", i);
> +				retval = TEST_ERR;
> +			}
> +			fclose(log[i]);
> +		}
> +		if (kmsg_drop_device(minors[i])) {
> +			printf("Failed to delete device file %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +		if (kmsg_cmd_buffer_del(fd, &minors[i])) {
> +			printf("Failed to delete buffer %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +	}
> +	close(fd);
> +	return retval;
> +}
> diff --git a/tools/testing/selftests/kmsg/test-buffer-buf-torture.c b/tools/testing/selftests/kmsg/test-buffer-buf-torture.c
> new file mode 100644
> index 0000000..700a2fa
> --- /dev/null
> +++ b/tools/testing/selftests/kmsg/test-buffer-buf-torture.c
> @@ -0,0 +1,139 @@
> +#include <stddef.h>
> +#include <stdint.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <kmsg-api.h>
> +
> +#include "kmsg-test.h"
> +
> +#define SOME_BUFF_SIZE 4096
> +
> +int kmsg_test_buffer_buf_torture(const struct kmsg_test_args *args)
> +{
> +	int i, iter;
> +	int fd = open(DEV_KMSG, O_RDWR);
> +	struct kmsg_cmd_buffer_add cmd = { 0 };
> +	int minors[] = { -1, -1, -1, -1 };
> +	FILE *fds[ARRAY_SIZE(minors)];
> +	FILE *log[ARRAY_SIZE(minors)];
> +	int retval = TEST_OK;
> +	char buff[SOME_BUFF_SIZE];
> +	ssize_t s;
> +	int logfd;
> +	uint32_t size, done;
> +	uint32_t max_size;
> +
> +	memset(buff, 'A', ARRAY_SIZE(buff));
> +	buff[ARRAY_SIZE(buff) - 1] = 0;
> +
> +	if (fd < 0) {
> +		printf("Failed: cannot open %s\n", DEV_KMSG);
> +		return TEST_ERR;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		fds[i] = NULL;
> +		log[i] = NULL;
> +		cmd.size = KMSG_REQUESTED_BUF_SIZE;
> +		cmd.mode = 0662;
> +		if (kmsg_cmd_buffer_add(fd, &cmd)) {
> +			printf("Failed to add buffer\n");
> +			goto error;
> +		}
> +		if (cmd.minor < 0) {
> +			printf("Minor number < 0\n");
> +			goto error;
> +		}
> +		minors[i] = cmd.minor;
> +
> +		fds[i] = kmsg_get_device(minors[i], "w");
> +		if (!fds[i]) {
> +			printf("Cannot get device %d for write\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(fds[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +		log[i] = kmsg_get_device(minors[i], "r");
> +		if (!log[i]) {
> +			printf("Cannot get device %d for read\n", i);
> +			goto error;
> +		}
> +		size = 0;
> +		if (kmsg_cmd_get_buf_size(fileno(log[i]), &size)) {
> +			printf("Cannot get buf size on defice %d\n", i);
> +			goto error;
> +		}
> +		if (size != KMSG_REQUESTED_BUF_SIZE) {
> +			printf("Invalid buf size on device %d\n", i);
> +			goto error;
> +		}
> +
> +		logfd = fileno(fds[i]);
> +		if (kmsg_cmd_clear(logfd)) {
> +			printf("Cannot clear buffer on device %d\n", i);
> +			goto error;
> +		}
> +
> +		iter = 0;
> +		while (done < (KMSG_REQUESTED_BUF_SIZE * 2)) {
> +			s = write(logfd, buff, ARRAY_SIZE(buff));
> +			if (s < 0) {
> +				printf("Cannot write %d to device %d, %s\n",
> +						    iter, i, strerror(errno));
> +				goto error;
> +			}
> +			done += s;
> +
> +			max_size = 0;
> +			if (kmsg_cmd_get_read_size_max(logfd, &max_size)) {
> +				printf("Cannot get max_size on device %d\n", i);
> +				goto error;
> +			}
> +			if (!max_size) {
> +				printf("Expected non-zero max_size on %d\n", i);
> +				goto error;
> +			}
> +
> +			iter++;
> +		}
> +	}
> +
> +	goto cleanup;
> +
> +error:
> +	retval = TEST_ERR;
> +
> +cleanup:
> +	for (i = 0; i < ARRAY_SIZE(minors); i++) {
> +		if (minors[i] < 0)
> +			continue;
> +		if (fds[i])
> +			fclose(fds[i]);
> +		if (log[i]) {
> +			if (kmsg_cmd_clear(fileno(log[i]))) {
> +				printf("Failed to clear device %d\n", i);
> +				retval = TEST_ERR;
> +			}
> +			fclose(log[i]);
> +		}
> +		if (kmsg_drop_device(minors[i])) {
> +			printf("Failed to delete device file %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +		if (kmsg_cmd_buffer_del(fd, &minors[i])) {
> +			printf("Failed to delete buffer %d\n", i);
> +			retval = TEST_ERR;
> +		}
> +	}
> +	close(fd);
> +	return retval;
> +}
> 


-- 
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
shuahkh@osg.samsung.com | (970) 217-8978