From f50582649f8eee73f59aff95fadd9a963ed4ffea Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 18 Aug 2016 22:57:53 -0400 Subject: logind: update empty and "infinity" handling for [User]TasksMax (#3835) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The parsing functions for [User]TasksMax were inconsistent. Empty string and "infinity" were interpreted as no limit for TasksMax but not accepted for UserTasksMax. Update them so that they're consistent with other knobs. * Empty string indicates the default value. * "infinity" indicates no limit. While at it, replace opencoded (uint64_t) -1 with CGROUP_LIMIT_MAX in TasksMax handling. v2: Update empty string to indicate the default value as suggested by Zbigniew Jędrzejewski-Szmek. v3: Fixed empty UserTasksMax handling. --- man/logind.conf.xml | 5 +++-- src/basic/cgroup-util.h | 4 ++++ src/core/cgroup.c | 2 +- src/core/load-fragment.c | 20 +++++++++++++------- src/core/main.c | 2 +- src/login/logind-user.c | 13 ++++++++++++- src/login/logind.c | 3 ++- 7 files changed, 36 insertions(+), 13 deletions(-) diff --git a/man/logind.conf.xml b/man/logind.conf.xml index adba5a4131..cbee83357b 100644 --- a/man/logind.conf.xml +++ b/man/logind.conf.xml @@ -318,8 +318,9 @@ Sets the maximum number of OS tasks each user may run concurrently. This controls the TasksMax= setting of the per-user slice unit, see systemd.resource-control5 - for details. Defaults to 33%, which equals 10813 with the kernel's defaults on the host, but might be smaller - in OS containers. + for details. If assigned the special value infinity, no tasks limit is applied. + Defaults to 33%, which equals 10813 with the kernel's defaults on the host, but might be smaller in + OS containers. diff --git a/src/basic/cgroup-util.h b/src/basic/cgroup-util.h index a509a1775c..f1617a16be 100644 --- a/src/basic/cgroup-util.h +++ b/src/basic/cgroup-util.h @@ -112,6 +112,10 @@ static inline bool CGROUP_BLKIO_WEIGHT_IS_OK(uint64_t x) { (x >= CGROUP_BLKIO_WEIGHT_MIN && x <= CGROUP_BLKIO_WEIGHT_MAX); } +/* Default resource limits */ +#define DEFAULT_TASKS_MAX_PERCENTAGE 15U /* 15% of PIDs, 4915 on default settings */ +#define DEFAULT_USER_TASKS_MAX_PERCENTAGE 33U /* 33% of PIDs, 10813 on default settings */ + /* * General rules: * diff --git a/src/core/cgroup.c b/src/core/cgroup.c index 910a64b4da..ca3c3366f3 100644 --- a/src/core/cgroup.c +++ b/src/core/cgroup.c @@ -952,7 +952,7 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) { if ((mask & CGROUP_MASK_PIDS) && !is_root) { - if (c->tasks_max != (uint64_t) -1) { + if (c->tasks_max != CGROUP_LIMIT_MAX) { char buf[DECIMAL_STR_MAX(uint64_t) + 2]; sprintf(buf, "%" PRIu64 "\n", c->tasks_max); diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c index 4ad6c4d79b..d5185cf6a0 100644 --- a/src/core/load-fragment.c +++ b/src/core/load-fragment.c @@ -2999,30 +2999,36 @@ int config_parse_tasks_max( void *data, void *userdata) { - uint64_t *tasks_max = data, u; + uint64_t *tasks_max = data, v; + Unit *u = userdata; int r; - if (isempty(rvalue) || streq(rvalue, "infinity")) { - *tasks_max = (uint64_t) -1; + if (isempty(rvalue)) { + *tasks_max = u->manager->default_tasks_max; + return 0; + } + + if (streq(rvalue, "infinity")) { + *tasks_max = CGROUP_LIMIT_MAX; return 0; } r = parse_percent(rvalue); if (r < 0) { - r = safe_atou64(rvalue, &u); + r = safe_atou64(rvalue, &v); if (r < 0) { log_syntax(unit, LOG_ERR, filename, line, r, "Maximum tasks value '%s' invalid. Ignoring.", rvalue); return 0; } } else - u = system_tasks_max_scale(r, 100U); + v = system_tasks_max_scale(r, 100U); - if (u <= 0 || u >= UINT64_MAX) { + if (v <= 0 || v >= UINT64_MAX) { log_syntax(unit, LOG_ERR, filename, line, 0, "Maximum tasks value '%s' out of range. Ignoring.", rvalue); return 0; } - *tasks_max = u; + *tasks_max = v; return 0; } diff --git a/src/core/main.c b/src/core/main.c index 02324d325e..c7c6df3447 100644 --- a/src/core/main.c +++ b/src/core/main.c @@ -1559,7 +1559,7 @@ int main(int argc, char *argv[]) { (void) reset_all_signal_handlers(); (void) ignore_signals(SIGNALS_IGNORE, -1); - arg_default_tasks_max = system_tasks_max_scale(15U, 100U); /* 15% the system PIDs equals 4915 by default. */ + arg_default_tasks_max = system_tasks_max_scale(DEFAULT_TASKS_MAX_PERCENTAGE, 100U); if (parse_config_file() < 0) { error_message = "Failed to parse config file"; diff --git a/src/login/logind-user.c b/src/login/logind-user.c index 11951aca5b..e0e73b034d 100644 --- a/src/login/logind-user.c +++ b/src/login/logind-user.c @@ -26,6 +26,7 @@ #include "bus-common-errors.h" #include "bus-error.h" #include "bus-util.h" +#include "cgroup-util.h" #include "clean-ipc.h" #include "conf-parser.h" #include "escape.h" @@ -896,7 +897,17 @@ int config_parse_user_tasks_max( assert(rvalue); assert(data); - /* First, try to parse as percentage */ + if (isempty(rvalue)) { + *m = system_tasks_max_scale(DEFAULT_USER_TASKS_MAX_PERCENTAGE, 100U); + return 0; + } + + if (streq(rvalue, "infinity")) { + *m = CGROUP_LIMIT_MAX; + return 0; + } + + /* Try to parse as percentage */ r = parse_percent(rvalue); if (r >= 0) k = system_tasks_max_scale(r, 100U); diff --git a/src/login/logind.c b/src/login/logind.c index 5ce36d28c7..bbbf4aef57 100644 --- a/src/login/logind.c +++ b/src/login/logind.c @@ -38,6 +38,7 @@ #include "signal-util.h" #include "strv.h" #include "udev-util.h" +#include "cgroup-util.h" static void manager_free(Manager *m); @@ -62,7 +63,7 @@ static void manager_reset_config(Manager *m) { m->idle_action = HANDLE_IGNORE; m->runtime_dir_size = physical_memory_scale(10U, 100U); /* 10% */ - m->user_tasks_max = system_tasks_max_scale(33U, 100U); /* 33% */ + m->user_tasks_max = system_tasks_max_scale(DEFAULT_USER_TASKS_MAX_PERCENTAGE, 100U); /* 33% */ m->sessions_max = 8192; m->inhibitors_max = 8192; -- cgit v1.2.3-54-g00ecf