diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/Makefile | 19 | ||||
| -rw-r--r-- | tools/cgroup/.gitignore | 1 | ||||
| -rw-r--r-- | tools/cgroup/Makefile | 11 | ||||
| -rw-r--r-- | tools/cgroup/cgroup_event_listener.c | 110 |
4 files changed, 132 insertions, 9 deletions
diff --git a/tools/Makefile b/tools/Makefile index 1f9a529fe544..fc57a28abca1 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -3,6 +3,7 @@ include scripts/Makefile.include help: @echo 'Possible targets:' @echo '' + @echo ' cgroup - cgroup tools' @echo ' cpupower - a tool for all things x86 CPU power' @echo ' firewire - the userspace part of nosy, an IEEE-1394 traffic sniffer' @echo ' lguest - a minimal 32-bit x86 hypervisor' @@ -33,7 +34,7 @@ help: cpupower: FORCE $(call descend,power/$@) -firewire lguest perf usb virtio vm: FORCE +cgroup firewire lguest perf usb virtio vm: FORCE $(call descend,$@) selftests: FORCE @@ -45,7 +46,7 @@ turbostat x86_energy_perf_policy: FORCE cpupower_install: $(call descend,power/$(@:_install=),install) -firewire_install lguest_install perf_install usb_install virtio_install vm_install: +cgroup_install firewire_install lguest_install perf_install usb_install virtio_install vm_install: $(call descend,$(@:_install=),install) selftests_install: @@ -54,14 +55,14 @@ selftests_install: turbostat_install x86_energy_perf_policy_install: $(call descend,power/x86/$(@:_install=),install) -install: cpupower_install firewire_install lguest_install perf_install \ - selftests_install turbostat_install usb_install virtio_install \ - vm_install x86_energy_perf_policy_install +install: cgroup_install cpupower_install firewire_install lguest_install \ + perf_install selftests_install turbostat_install usb_install \ + virtio_install vm_install x86_energy_perf_policy_install cpupower_clean: $(call descend,power/cpupower,clean) -firewire_clean lguest_clean perf_clean usb_clean virtio_clean vm_clean: +cgroup_clean firewire_clean lguest_clean perf_clean usb_clean virtio_clean vm_clean: $(call descend,$(@:_clean=),clean) selftests_clean: @@ -70,8 +71,8 @@ selftests_clean: turbostat_clean x86_energy_perf_policy_clean: $(call descend,power/x86/$(@:_clean=),clean) -clean: cpupower_clean firewire_clean lguest_clean perf_clean selftests_clean \ - turbostat_clean usb_clean virtio_clean vm_clean \ - x86_energy_perf_policy_clean +clean: cgroup_clean cpupower_clean firewire_clean lguest_clean perf_clean \ + selftests_clean turbostat_clean usb_clean virtio_clean \ + vm_clean x86_energy_perf_policy_clean .PHONY: FORCE diff --git a/tools/cgroup/.gitignore b/tools/cgroup/.gitignore new file mode 100644 index 000000000000..633cd9b874f9 --- /dev/null +++ b/tools/cgroup/.gitignore @@ -0,0 +1 @@ +cgroup_event_listener diff --git a/tools/cgroup/Makefile b/tools/cgroup/Makefile new file mode 100644 index 000000000000..b4286196b763 --- /dev/null +++ b/tools/cgroup/Makefile @@ -0,0 +1,11 @@ +# Makefile for cgroup tools + +CC = $(CROSS_COMPILE)gcc +CFLAGS = -Wall -Wextra + +all: cgroup_event_listener +%: %.c + $(CC) $(CFLAGS) -o $@ $^ + +clean: + $(RM) cgroup_event_listener diff --git a/tools/cgroup/cgroup_event_listener.c b/tools/cgroup/cgroup_event_listener.c new file mode 100644 index 000000000000..3e082f96dc12 --- /dev/null +++ b/tools/cgroup/cgroup_event_listener.c @@ -0,0 +1,110 @@ +/* + * cgroup_event_listener.c - Simple listener of cgroup events + * + * Copyright (C) Kirill A. Shutemov <kirill@shutemov.name> + */ + +#include <assert.h> +#include <errno.h> +#include <fcntl.h> +#include <libgen.h> +#include <limits.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +#include <sys/eventfd.h> + +#define USAGE_STR "Usage: cgroup_event_listener <path-to-control-file> <args>\n" + +int main(int argc, char **argv) +{ + int efd = -1; + int cfd = -1; + int event_control = -1; + char event_control_path[PATH_MAX]; + char line[LINE_MAX]; + int ret; + + if (argc != 3) { + fputs(USAGE_STR, stderr); + return 1; + } + + cfd = open(argv[1], O_RDONLY); + if (cfd == -1) { + fprintf(stderr, "Cannot open %s: %s\n", argv[1], + strerror(errno)); + goto out; + } + + ret = snprintf(event_control_path, PATH_MAX, "%s/cgroup.event_control", + dirname(argv[1])); + if (ret >= PATH_MAX) { + fputs("Path to cgroup.event_control is too long\n", stderr); + goto out; + } + + event_control = open(event_control_path, O_WRONLY); + if (event_control == -1) { + fprintf(stderr, "Cannot open %s: %s\n", event_control_path, + strerror(errno)); + goto out; + } + + efd = eventfd(0, 0); + if (efd == -1) { + perror("eventfd() failed"); + goto out; + } + + ret = snprintf(line, LINE_MAX, "%d %d %s", efd, cfd, argv[2]); + if (ret >= LINE_MAX) { + fputs("Arguments string is too long\n", stderr); + goto out; + } + + ret = write(event_control, line, strlen(line) + 1); + if (ret == -1) { + perror("Cannot write to cgroup.event_control"); + goto out; + } + + while (1) { + uint64_t result; + + ret = read(efd, &result, sizeof(result)); + if (ret == -1) { + if (errno == EINTR) + continue; + perror("Cannot read from eventfd"); + break; + } + assert(ret == sizeof(result)); + + ret = access(event_control_path, W_OK); + if ((ret == -1) && (errno == ENOENT)) { + puts("The cgroup seems to have removed."); + ret = 0; + break; + } + + if (ret == -1) { + perror("cgroup.event_control " + "is not accessible any more"); + break; + } + + printf("%s %s: crossed\n", argv[1], argv[2]); + } + +out: + if (efd >= 0) + close(efd); + if (event_control >= 0) + close(event_control); + if (cfd >= 0) + close(cfd); + + return (ret != 0); +} |