| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <sys/xattr.h> |
| #include <unistd.h> |
| |
| #include "cgroup-util.h" |
| #include "fd-util.h" |
| #include "format-util.h" |
| #include "oomd-util.h" |
| #include "parse-util.h" |
| #include "path-util.h" |
| #include "procfs-util.h" |
| #include "signal-util.h" |
| #include "sort-util.h" |
| #include "stat-util.h" |
| #include "stdio-util.h" |
| |
| DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR( |
| oomd_cgroup_ctx_hash_ops, |
| char, |
| string_hash_func, |
| string_compare_func, |
| OomdCGroupContext, |
| oomd_cgroup_context_free); |
| |
| static int log_kill(pid_t pid, int sig, void *userdata) { |
| log_debug("oomd attempting to kill " PID_FMT " with %s", pid, signal_to_string(sig)); |
| return 0; |
| } |
| |
| static int increment_oomd_xattr(const char *path, const char *xattr, uint64_t num_procs_killed) { |
| _cleanup_free_ char *value = NULL; |
| char buf[DECIMAL_STR_MAX(uint64_t) + 1]; |
| uint64_t curr_count = 0; |
| int r; |
| |
| assert(path); |
| assert(xattr); |
| |
| r = cg_get_xattr_malloc(SYSTEMD_CGROUP_CONTROLLER, path, xattr, &value); |
| if (r < 0 && r != -ENODATA) |
| return r; |
| |
| if (!isempty(value)) { |
| r = safe_atou64(value, &curr_count); |
| if (r < 0) |
| return r; |
| } |
| |
| if (curr_count > UINT64_MAX - num_procs_killed) |
| return -EOVERFLOW; |
| |
| xsprintf(buf, "%"PRIu64, curr_count + num_procs_killed); |
| r = cg_set_xattr(SYSTEMD_CGROUP_CONTROLLER, path, xattr, buf, strlen(buf), 0); |
| if (r < 0) |
| return r; |
| |
| return 0; |
| } |
| |
| OomdCGroupContext *oomd_cgroup_context_free(OomdCGroupContext *ctx) { |
| if (!ctx) |
| return NULL; |
| |
| free(ctx->path); |
| return mfree(ctx); |
| } |
| |
| int oomd_pressure_above(Hashmap *h, usec_t duration, Set **ret) { |
| _cleanup_set_free_ Set *targets = NULL; |
| OomdCGroupContext *ctx; |
| char *key; |
| int r; |
| |
| assert(h); |
| assert(ret); |
| |
| targets = set_new(NULL); |
| if (!targets) |
| return -ENOMEM; |
| |
| HASHMAP_FOREACH_KEY(ctx, key, h) { |
| if (ctx->memory_pressure.avg10 > ctx->mem_pressure_limit) { |
| usec_t diff; |
| |
| if (ctx->last_hit_mem_pressure_limit == 0) |
| ctx->last_hit_mem_pressure_limit = now(CLOCK_MONOTONIC); |
| |
| diff = now(CLOCK_MONOTONIC) - ctx->last_hit_mem_pressure_limit; |
| if (diff >= duration) { |
| r = set_put(targets, ctx); |
| if (r < 0) |
| return -ENOMEM; |
| } |
| } else |
| ctx->last_hit_mem_pressure_limit = 0; |
| } |
| |
| if (!set_isempty(targets)) { |
| *ret = TAKE_PTR(targets); |
| return 1; |
| } |
| |
| *ret = NULL; |
| return 0; |
| } |
| |
| bool oomd_memory_reclaim(Hashmap *h) { |
| uint64_t pgscan = 0, pgscan_of = 0, last_pgscan = 0, last_pgscan_of = 0; |
| OomdCGroupContext *ctx; |
| |
| assert(h); |
| |
| /* If sum of all the current pgscan values are greater than the sum of all the last_pgscan values, |
| * there was reclaim activity. Used along with pressure checks to decide whether to take action. */ |
| |
| HASHMAP_FOREACH(ctx, h) { |
| uint64_t sum; |
| |
| sum = pgscan + ctx->pgscan; |
| if (sum < pgscan || sum < ctx->pgscan) |
| pgscan_of++; /* count overflows */ |
| pgscan = sum; |
| |
| sum = last_pgscan + ctx->last_pgscan; |
| if (sum < last_pgscan || sum < ctx->last_pgscan) |
| last_pgscan_of++; /* count overflows */ |
| last_pgscan = sum; |
| } |
| |
| /* overflow counts are the same, return sums comparison */ |
| if (last_pgscan_of == pgscan_of) |
| return pgscan > last_pgscan; |
| |
| return pgscan_of > last_pgscan_of; |
| } |
| |
| bool oomd_swap_free_below(const OomdSystemContext *ctx, uint64_t threshold_percent) { |
| uint64_t swap_threshold; |
| |
| assert(ctx); |
| assert(threshold_percent <= 100); |
| |
| swap_threshold = ctx->swap_total * threshold_percent / ((uint64_t) 100); |
| return (ctx->swap_total - ctx->swap_used) < swap_threshold; |
| } |
| |
| int oomd_sort_cgroup_contexts(Hashmap *h, oomd_compare_t compare_func, const char *prefix, OomdCGroupContext ***ret) { |
| _cleanup_free_ OomdCGroupContext **sorted = NULL; |
| OomdCGroupContext *item; |
| size_t k = 0; |
| |
| assert(h); |
| assert(compare_func); |
| assert(ret); |
| |
| sorted = new0(OomdCGroupContext*, hashmap_size(h)); |
| if (!sorted) |
| return -ENOMEM; |
| |
| HASHMAP_FOREACH(item, h) { |
| if (item->path && prefix && !path_startswith(item->path, prefix)) |
| continue; |
| |
| sorted[k++] = item; |
| } |
| |
| typesafe_qsort(sorted, k, compare_func); |
| |
| *ret = TAKE_PTR(sorted); |
| |
| assert(k <= INT_MAX); |
| return (int) k; |
| } |
| |
| int oomd_cgroup_kill(const char *path, bool recurse, bool dry_run) { |
| _cleanup_set_free_ Set *pids_killed = NULL; |
| int r; |
| |
| assert(path); |
| |
| if (dry_run) { |
| _cleanup_free_ char *cg_path = NULL; |
| |
| r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, NULL, &cg_path); |
| if (r < 0) |
| return r; |
| |
| log_debug("oomd dry-run: Would have tried to kill %s with recurse=%s", cg_path, true_false(recurse)); |
| return 0; |
| } |
| |
| pids_killed = set_new(NULL); |
| if (!pids_killed) |
| return -ENOMEM; |
| |
| if (recurse) |
| r = cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, path, SIGKILL, CGROUP_IGNORE_SELF, pids_killed, log_kill, NULL); |
| else |
| r = cg_kill(SYSTEMD_CGROUP_CONTROLLER, path, SIGKILL, CGROUP_IGNORE_SELF, pids_killed, log_kill, NULL); |
| if (r < 0) |
| return r; |
| |
| r = increment_oomd_xattr(path, "user.systemd_oomd_kill", set_size(pids_killed)); |
| if (r < 0) |
| log_debug_errno(r, "Failed to set user.systemd_oomd_kill on kill: %m"); |
| |
| return set_size(pids_killed) != 0; |
| } |
| |
| int oomd_kill_by_pgscan(Hashmap *h, const char *prefix, bool dry_run) { |
| _cleanup_free_ OomdCGroupContext **sorted = NULL; |
| int r; |
| |
| assert(h); |
| |
| r = oomd_sort_cgroup_contexts(h, compare_pgscan, prefix, &sorted); |
| if (r < 0) |
| return r; |
| |
| for (int i = 0; i < r; i++) { |
| if (sorted[i]->pgscan == 0) |
| break; |
| |
| r = oomd_cgroup_kill(sorted[i]->path, true, dry_run); |
| if (r > 0 || r == -ENOMEM) |
| break; |
| } |
| |
| return r; |
| } |
| |
| int oomd_kill_by_swap_usage(Hashmap *h, bool dry_run) { |
| _cleanup_free_ OomdCGroupContext **sorted = NULL; |
| int r; |
| |
| assert(h); |
| |
| r = oomd_sort_cgroup_contexts(h, compare_swap_usage, NULL, &sorted); |
| if (r < 0) |
| return r; |
| |
| /* Try to kill cgroups with non-zero swap usage until we either succeed in |
| * killing or we get to a cgroup with no swap usage. */ |
| for (int i = 0; i < r; i++) { |
| if (sorted[i]->swap_usage == 0) |
| break; |
| |
| r = oomd_cgroup_kill(sorted[i]->path, true, dry_run); |
| if (r > 0 || r == -ENOMEM) |
| break; |
| } |
| |
| return r; |
| } |
| |
| int oomd_cgroup_context_acquire(const char *path, OomdCGroupContext **ret) { |
| _cleanup_(oomd_cgroup_context_freep) OomdCGroupContext *ctx = NULL; |
| _cleanup_free_ char *p = NULL, *val = NULL; |
| bool is_root; |
| int r; |
| |
| assert(path); |
| assert(ret); |
| |
| ctx = new0(OomdCGroupContext, 1); |
| if (!ctx) |
| return -ENOMEM; |
| |
| is_root = empty_or_root(path); |
| |
| r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, "memory.pressure", &p); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting cgroup memory pressure path from %s: %m", path); |
| |
| r = read_resource_pressure(p, PRESSURE_TYPE_FULL, &ctx->memory_pressure); |
| if (r < 0) |
| return log_debug_errno(r, "Error parsing memory pressure from %s: %m", p); |
| |
| if (is_root) { |
| r = procfs_memory_get_used(&ctx->current_memory_usage); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting memory used from procfs: %m"); |
| } else { |
| r = cg_get_attribute_as_uint64(SYSTEMD_CGROUP_CONTROLLER, path, "memory.current", &ctx->current_memory_usage); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting memory.current from %s: %m", path); |
| |
| r = cg_get_attribute_as_uint64(SYSTEMD_CGROUP_CONTROLLER, path, "memory.min", &ctx->memory_min); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting memory.min from %s: %m", path); |
| |
| r = cg_get_attribute_as_uint64(SYSTEMD_CGROUP_CONTROLLER, path, "memory.low", &ctx->memory_low); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting memory.low from %s: %m", path); |
| |
| r = cg_get_attribute_as_uint64(SYSTEMD_CGROUP_CONTROLLER, path, "memory.swap.current", &ctx->swap_usage); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting memory.swap.current from %s: %m", path); |
| |
| r = cg_get_keyed_attribute(SYSTEMD_CGROUP_CONTROLLER, path, "memory.stat", STRV_MAKE("pgscan"), &val); |
| if (r < 0) |
| return log_debug_errno(r, "Error getting pgscan from memory.stat under %s: %m", path); |
| |
| r = safe_atou64(val, &ctx->pgscan); |
| if (r < 0) |
| return log_debug_errno(r, "Error converting pgscan value to uint64_t: %m"); |
| } |
| |
| ctx->path = strdup(empty_to_root(path)); |
| if (!ctx->path) |
| return -ENOMEM; |
| |
| *ret = TAKE_PTR(ctx); |
| return 0; |
| } |
| |
| int oomd_system_context_acquire(const char *proc_swaps_path, OomdSystemContext *ret) { |
| _cleanup_fclose_ FILE *f = NULL; |
| OomdSystemContext ctx = {}; |
| int r; |
| |
| assert(proc_swaps_path); |
| assert(ret); |
| |
| f = fopen(proc_swaps_path, "re"); |
| if (!f) |
| return -errno; |
| |
| (void) fscanf(f, "%*s %*s %*s %*s %*s\n"); |
| |
| for (;;) { |
| uint64_t total, used; |
| |
| r = fscanf(f, |
| "%*s " /* device/file */ |
| "%*s " /* type of swap */ |
| "%" PRIu64 " " /* swap size */ |
| "%" PRIu64 " " /* used */ |
| "%*s\n", /* priority */ |
| &total, &used); |
| |
| if (r == EOF && feof(f)) |
| break; |
| |
| if (r != 2) { |
| if (ferror(f)) |
| return log_debug_errno(errno, "Error reading from %s: %m", proc_swaps_path); |
| |
| return log_debug_errno(SYNTHETIC_ERRNO(EIO), |
| "Failed to parse values from %s: %m", proc_swaps_path); |
| } |
| |
| ctx.swap_total += total * 1024U; |
| ctx.swap_used += used * 1024U; |
| } |
| |
| *ret = ctx; |
| return 0; |
| } |
| |
| int oomd_insert_cgroup_context(Hashmap *old_h, Hashmap *new_h, const char *path) { |
| _cleanup_(oomd_cgroup_context_freep) OomdCGroupContext *curr_ctx = NULL; |
| OomdCGroupContext *old_ctx, *ctx; |
| int r; |
| |
| assert(new_h); |
| assert(path); |
| |
| r = oomd_cgroup_context_acquire(path, &curr_ctx); |
| if (r < 0) |
| return log_debug_errno(r, "Failed to get OomdCGroupContext for %s: %m", path); |
| |
| old_ctx = hashmap_get(old_h, path); |
| if (old_ctx) { |
| curr_ctx->last_pgscan = old_ctx->pgscan; |
| curr_ctx->mem_pressure_limit = old_ctx->mem_pressure_limit; |
| curr_ctx->last_hit_mem_pressure_limit = old_ctx->last_hit_mem_pressure_limit; |
| } |
| |
| ctx = TAKE_PTR(curr_ctx); |
| r = hashmap_put(new_h, ctx->path, ctx); |
| if (r < 0) |
| return r; |
| |
| return 0; |
| } |
| |
| void oomd_dump_swap_cgroup_context(const OomdCGroupContext *ctx, FILE *f, const char *prefix) { |
| char swap[FORMAT_BYTES_MAX]; |
| |
| assert(ctx); |
| assert(f); |
| |
| if (!empty_or_root(ctx->path)) |
| fprintf(f, |
| "%sPath: %s\n" |
| "%s\tSwap Usage: %s\n", |
| strempty(prefix), ctx->path, |
| strempty(prefix), format_bytes(swap, sizeof(swap), ctx->swap_usage)); |
| else |
| fprintf(f, |
| "%sPath: %s\n" |
| "%s\tSwap Usage: (see System Context)\n", |
| strempty(prefix), ctx->path, |
| strempty(prefix)); |
| } |
| |
| void oomd_dump_memory_pressure_cgroup_context(const OomdCGroupContext *ctx, FILE *f, const char *prefix) { |
| char tbuf[FORMAT_TIMESPAN_MAX], mem_use[FORMAT_BYTES_MAX]; |
| char mem_min[FORMAT_BYTES_MAX], mem_low[FORMAT_BYTES_MAX]; |
| |
| assert(ctx); |
| assert(f); |
| |
| fprintf(f, |
| "%sPath: %s\n" |
| "%s\tMemory Pressure Limit: %lu%%\n" |
| "%s\tPressure: Avg10: %lu.%02lu Avg60: %lu.%02lu Avg300: %lu.%02lu Total: %s\n" |
| "%s\tCurrent Memory Usage: %s\n", |
| strempty(prefix), ctx->path, |
| strempty(prefix), LOAD_INT(ctx->mem_pressure_limit), |
| strempty(prefix), |
| LOAD_INT(ctx->memory_pressure.avg10), LOAD_FRAC(ctx->memory_pressure.avg10), |
| LOAD_INT(ctx->memory_pressure.avg60), LOAD_FRAC(ctx->memory_pressure.avg60), |
| LOAD_INT(ctx->memory_pressure.avg300), LOAD_FRAC(ctx->memory_pressure.avg300), |
| format_timespan(tbuf, sizeof(tbuf), ctx->memory_pressure.total, USEC_PER_SEC), |
| strempty(prefix), format_bytes(mem_use, sizeof(mem_use), ctx->current_memory_usage)); |
| |
| if (!empty_or_root(ctx->path)) |
| fprintf(f, |
| "%s\tMemory Min: %s\n" |
| "%s\tMemory Low: %s\n" |
| "%s\tPgscan: %" PRIu64 "\n", |
| strempty(prefix), format_bytes_cgroup_protection(mem_min, sizeof(mem_min), ctx->memory_min), |
| strempty(prefix), format_bytes_cgroup_protection(mem_low, sizeof(mem_low), ctx->memory_low), |
| strempty(prefix), ctx->pgscan); |
| } |
| |
| void oomd_dump_system_context(const OomdSystemContext *ctx, FILE *f, const char *prefix) { |
| char used[FORMAT_BYTES_MAX], total[FORMAT_BYTES_MAX]; |
| |
| assert(ctx); |
| assert(f); |
| |
| fprintf(f, |
| "%sSwap: Used: %s Total: %s\n", |
| strempty(prefix), |
| format_bytes(used, sizeof(used), ctx->swap_used), |
| format_bytes(total, sizeof(total), ctx->swap_total)); |
| } |