diff options
Diffstat (limited to 'src/oom/oomd.c')
| -rw-r--r-- | src/oom/oomd.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/src/oom/oomd.c b/src/oom/oomd.c new file mode 100644 index 0000000..ecc2eda --- /dev/null +++ b/src/oom/oomd.c @@ -0,0 +1,197 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <getopt.h> + +#include "build.h" +#include "bus-log-control-api.h" +#include "bus-object.h" +#include "cgroup-util.h" +#include "conf-parser.h" +#include "daemon-util.h" +#include "fileio.h" +#include "log.h" +#include "main-func.h" +#include "oomd-manager-bus.h" +#include "oomd-manager.h" +#include "parse-util.h" +#include "pretty-print.h" +#include "psi-util.h" +#include "signal-util.h" + +static bool arg_dry_run = false; +static int arg_swap_used_limit_permyriad = -1; +static int arg_mem_pressure_limit_permyriad = -1; +static usec_t arg_mem_pressure_usec = 0; + +static int parse_config(void) { + static const ConfigTableItem items[] = { + { "OOM", "SwapUsedLimit", config_parse_permyriad, 0, &arg_swap_used_limit_permyriad }, + { "OOM", "DefaultMemoryPressureLimit", config_parse_permyriad, 0, &arg_mem_pressure_limit_permyriad }, + { "OOM", "DefaultMemoryPressureDurationSec", config_parse_sec, 0, &arg_mem_pressure_usec }, + {} + }; + + return config_parse_config_file("oomd.conf", "OOM\0", + config_item_table_lookup, items, + CONFIG_PARSE_WARN, NULL); +} + +static int help(void) { + _cleanup_free_ char *link = NULL; + int r; + + r = terminal_urlify_man("systemd-oomd", "8", &link); + if (r < 0) + return log_oom(); + + printf("%s [OPTIONS...]\n\n" + "Run the userspace out-of-memory (OOM) killer.\n\n" + " -h --help Show this help\n" + " --version Show package version\n" + " --dry-run Only print destructive actions instead of doing them\n" + " --bus-introspect=PATH Write D-Bus XML introspection data\n" + "\nSee the %s for details.\n", + program_invocation_short_name, + link); + + return 0; +} + +static int parse_argv(int argc, char *argv[]) { + enum { + ARG_VERSION = 0x100, + ARG_DRY_RUN, + ARG_BUS_INTROSPECT, + }; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "dry-run", no_argument, NULL, ARG_DRY_RUN }, + { "bus-introspect", required_argument, NULL, ARG_BUS_INTROSPECT }, + {} + }; + + int c; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) + + switch (c) { + + case 'h': + return help(); + + case ARG_VERSION: + return version(); + + case ARG_DRY_RUN: + arg_dry_run = true; + break; + + case ARG_BUS_INTROSPECT: + return bus_introspect_implementations( + stdout, + optarg, + BUS_IMPLEMENTATIONS(&manager_object, + &log_control_object)); + + case '?': + return -EINVAL; + + default: + assert_not_reached(); + } + + if (optind < argc) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "This program takes no arguments."); + + return 1; +} + +static int run(int argc, char *argv[]) { + _unused_ _cleanup_(notify_on_cleanup) const char *notify_msg = NULL; + _cleanup_(manager_freep) Manager *m = NULL; + _cleanup_free_ char *swap = NULL; + unsigned long long s = 0; + CGroupMask mask; + int r; + + log_setup(); + + r = parse_argv(argc, argv); + if (r <= 0) + return r; + + r = parse_config(); + if (r < 0) + return r; + + /* Do some basic requirement checks for running systemd-oomd. It's not exhaustive as some of the other + * requirements do not have a reliable means to check for in code. */ + + int n = sd_listen_fds(0); + if (n > 1) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Received too many file descriptors"); + + int fd = n == 1 ? SD_LISTEN_FDS_START : -1; + + /* SwapTotal is always available in /proc/meminfo and defaults to 0, even on swap-disabled kernels. */ + r = get_proc_field("/proc/meminfo", "SwapTotal", WHITESPACE, &swap); + if (r < 0) + return log_error_errno(r, "Failed to get SwapTotal from /proc/meminfo: %m"); + + r = safe_atollu(swap, &s); + if (r < 0 || s == 0) + log_warning("No swap; memory pressure usage will be degraded"); + + if (!is_pressure_supported()) + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "Pressure Stall Information (PSI) is not supported"); + + r = cg_all_unified(); + if (r < 0) + return log_error_errno(r, "Failed to determine whether the unified cgroups hierarchy is used: %m"); + if (r == 0) + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "Requires the unified cgroups hierarchy"); + + r = cg_mask_supported(&mask); + if (r < 0) + return log_error_errno(r, "Failed to get supported cgroup controllers: %m"); + + if (!FLAGS_SET(mask, CGROUP_MASK_MEMORY)) + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "Requires the cgroup memory controller."); + + assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, -1) >= 0); + + if (arg_mem_pressure_usec > 0 && arg_mem_pressure_usec < 1 * USEC_PER_SEC) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "DefaultMemoryPressureDurationSec= must be 0 or at least 1s"); + + r = manager_new(&m); + if (r < 0) + return log_error_errno(r, "Failed to create manager: %m"); + + r = manager_start( + m, + arg_dry_run, + arg_swap_used_limit_permyriad, + arg_mem_pressure_limit_permyriad, + arg_mem_pressure_usec, + fd); + if (r < 0) + return log_error_errno(r, "Failed to start up daemon: %m"); + + notify_msg = notify_start(NOTIFY_READY, NOTIFY_STOPPING); + + log_debug("systemd-oomd started%s.", arg_dry_run ? " in dry run mode" : ""); + + r = sd_event_loop(m->event); + if (r < 0) + return log_error_errno(r, "Event loop failed: %m"); + + return 0; +} + +DEFINE_MAIN_FUNCTION(run); |