Just a simple test/example utility for the vmpressure_fd(2) system call.
Signed-off-by: Anton Vorontsov anton.vorontsov@linaro.org --- tools/testing/vmpressure/.gitignore | 1 + tools/testing/vmpressure/Makefile | 30 ++++++++++ tools/testing/vmpressure/vmpressure-test.c | 93 ++++++++++++++++++++++++++++++ 3 files changed, 124 insertions(+) create mode 100644 tools/testing/vmpressure/.gitignore create mode 100644 tools/testing/vmpressure/Makefile create mode 100644 tools/testing/vmpressure/vmpressure-test.c
diff --git a/tools/testing/vmpressure/.gitignore b/tools/testing/vmpressure/.gitignore new file mode 100644 index 0000000..fe5e38c --- /dev/null +++ b/tools/testing/vmpressure/.gitignore @@ -0,0 +1 @@ +vmpressure-test diff --git a/tools/testing/vmpressure/Makefile b/tools/testing/vmpressure/Makefile new file mode 100644 index 0000000..7545f3e --- /dev/null +++ b/tools/testing/vmpressure/Makefile @@ -0,0 +1,30 @@ +WARNINGS := -Wcast-align +WARNINGS += -Wformat +WARNINGS += -Wformat-security +WARNINGS += -Wformat-y2k +WARNINGS += -Wshadow +WARNINGS += -Winit-self +WARNINGS += -Wpacked +WARNINGS += -Wredundant-decls +WARNINGS += -Wstrict-aliasing=3 +WARNINGS += -Wswitch-default +WARNINGS += -Wno-system-headers +WARNINGS += -Wundef +WARNINGS += -Wwrite-strings +WARNINGS += -Wbad-function-cast +WARNINGS += -Wmissing-declarations +WARNINGS += -Wmissing-prototypes +WARNINGS += -Wnested-externs +WARNINGS += -Wold-style-definition +WARNINGS += -Wstrict-prototypes +WARNINGS += -Wdeclaration-after-statement + +CFLAGS = -O3 -g -std=gnu99 $(WARNINGS) + +PROGRAMS = vmpressure-test + +all: $(PROGRAMS) + +clean: + rm -f $(PROGRAMS) *.o +.PHONY: clean diff --git a/tools/testing/vmpressure/vmpressure-test.c b/tools/testing/vmpressure/vmpressure-test.c new file mode 100644 index 0000000..1e448be --- /dev/null +++ b/tools/testing/vmpressure/vmpressure-test.c @@ -0,0 +1,93 @@ +/* + * vmpressure_fd(2) test utility + * + * Copyright 2011-2012 Pekka Enberg penberg@kernel.org + * Copyright 2011-2012 Linaro Ltd. + * Anton Vorontsov anton.vorontsov@linaro.org + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +/* TODO: glibc wrappers */ +#include "../../../include/linux/vmpressure.h" + +#if defined(__x86_64__) +#include "../../../arch/x86/include/generated/asm/unistd_64.h" +#endif +#if defined(__arm__) +#include "../../../arch/arm/include/asm/unistd.h" +#endif + +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <stdio.h> +#include <poll.h> + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +static void pexit(const char *str) +{ + perror(str); + exit(1); +} + +static int vmpressure_fd(struct vmpressure_config *config) +{ + config->size = sizeof(*config); + + return syscall(__NR_vmpressure_fd, config); +} + +int main(int argc, char *argv[]) +{ + struct vmpressure_config config[] = { + /* + * We could just set the lowest priority, but we want to + * actually test if the thresholds work. + */ + { .threshold = VMPRESSURE_LOW }, + { .threshold = VMPRESSURE_MEDIUM }, + { .threshold = VMPRESSURE_OOM }, + }; + const size_t num = ARRAY_SIZE(config); + struct pollfd pfds[num]; + int i; + + for (i = 0; i < num; i++) { + pfds[i].fd = vmpressure_fd(&config[i]); + if (pfds[i].fd < 0) + pexit("vmpressure_fd failed"); + + pfds[i].events = POLLIN; + } + + while (poll(pfds, num, -1) > 0) { + for (i = 0; i < num; i++) { + struct vmpressure_event event; + + if (!pfds[i].revents) + continue; + + if (read(pfds[i].fd, &event, sizeof(event)) < 0) + pexit("read failed"); + + printf("VM pressure: 0x%.8x (threshold 0x%.8x)\n", + event.pressure, config[i].threshold); + } + } + + perror("poll failed\n"); + + for (i = 0; i < num; i++) { + if (close(pfds[i].fd) < 0) + pexit("close failed"); + } + + exit(1); + return 0; +}