Merge pull request #1239 from poettering/cgroup-pids

core: add support for the "pids" cgroup controller

10 files changed, 157 insertions, 7 deletions

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index baa7cc5488..48000d4e6e 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -22,10 +22,11 @@
 #include <fcntl.h>
 #include <fnmatch.h>
 
-#include "process-util.h"
+#include "cgroup-util.h"
 #include "path-util.h"
+#include "process-util.h"
 #include "special.h"
-#include "cgroup-util.h"
+
 #include "cgroup.h"
 
 #define CGROUP_CPU_QUOTA_PERIOD_USEC ((usec_t) 100 * USEC_PER_MSEC)
@@ -41,6 +42,7 @@ void cgroup_context_init(CGroupContext *c) {
         c->memory_limit = (uint64_t) -1;
         c->blockio_weight = (unsigned long) -1;
         c->startup_blockio_weight = (unsigned long) -1;
+        c->tasks_max = (uint64_t) -1;
 
         c->cpu_quota_per_sec_usec = USEC_INFINITY;
 }
@@ -106,6 +108,7 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 "%sBlockIOWeight=%lu\n"
                 "%sStartupBlockIOWeight=%lu\n"
                 "%sMemoryLimit=%" PRIu64 "\n"
+                "%sTasksMax=%" PRIu64 "\n"
                 "%sDevicePolicy=%s\n"
                 "%sDelegate=%s\n",
                 prefix, yes_no(c->cpu_accounting),
@@ -117,6 +120,7 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 prefix, c->blockio_weight,
                 prefix, c->startup_blockio_weight,
                 prefix, c->memory_limit,
+                prefix, c->tasks_max,
                 prefix, cgroup_device_policy_to_string(c->device_policy),
                 prefix, yes_no(c->delegate));
 
@@ -466,6 +470,21 @@ void cgroup_context_apply(CGroupContext *c, CGroupMask mask, const char *path, M
                                 log_debug("Ignoring device %s while writing cgroup attribute.", a->path);
                 }
         }
+
+        if ((mask & CGROUP_MASK_PIDS) && !is_root) {
+
+                if (c->tasks_max != (uint64_t) -1) {
+                        char buf[DECIMAL_STR_MAX(uint64_t) + 2];
+
+                        sprintf(buf, "%" PRIu64 "\n", c->tasks_max);
+                        r = cg_set_attribute("pids", path, "pids.max", buf);
+                } else
+                        r = cg_set_attribute("pids", path, "pids.max", "max");
+
+                if (r < 0)
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set pids.max on %s: %m", path);
+        }
 }
 
 CGroupMask cgroup_context_get_mask(CGroupContext *c) {
@@ -494,6 +513,10 @@ CGroupMask cgroup_context_get_mask(CGroupContext *c) {
             c->device_policy != CGROUP_AUTO)
                 mask |= CGROUP_MASK_DEVICES;
 
+        if (c->tasks_accounting ||
+            c->tasks_max != (uint64_t) -1)
+                mask |= CGROUP_MASK_PIDS;
+
         return mask;
 }
 
@@ -1459,6 +1482,28 @@ int unit_get_memory_current(Unit *u, uint64_t *ret) {
         return safe_atou64(v, ret);
 }
 
+int unit_get_tasks_current(Unit *u, uint64_t *ret) {
+        _cleanup_free_ char *v = NULL;
+        int r;
+
+        assert(u);
+        assert(ret);
+
+        if (!u->cgroup_path)
+                return -ENODATA;
+
+        if ((u->cgroup_realized_mask & CGROUP_MASK_PIDS) == 0)
+                return -ENODATA;
+
+        r = cg_get_attribute("pids", u->cgroup_path, "pids.current", &v);
+        if (r == -ENOENT)
+                return -ENODATA;
+        if (r < 0)
+                return r;
+
+        return safe_atou64(v, ret);
+}
+
 static int unit_get_cpu_usage_raw(Unit *u, nsec_t *ret) {
         _cleanup_free_ char *v = NULL;
         uint64_t ns;
diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index 438f5bf50f..3ba09d56a4 100644
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -72,6 +72,7 @@ struct CGroupContext {
         bool cpu_accounting;
         bool blockio_accounting;
         bool memory_accounting;
+        bool tasks_accounting;
 
         unsigned long cpu_shares;
         unsigned long startup_cpu_shares;
@@ -88,6 +89,8 @@ struct CGroupContext {
         LIST_HEAD(CGroupDeviceAllow, device_allow);
 
         bool delegate;
+
+        uint64_t tasks_max;
 };
 
 #include "unit.h"
@@ -137,6 +140,7 @@ int unit_search_main_pid(Unit *u, pid_t *ret);
 int unit_watch_all_pids(Unit *u);
 
 int unit_get_memory_current(Unit *u, uint64_t *ret);
+int unit_get_tasks_current(Unit *u, uint64_t *ret);
 int unit_get_cpu_usage(Unit *u, nsec_t *ret);
 int unit_reset_cpu_usage(Unit *u);
 
diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
index ba2f4e53b9..94de92c3dd 100644
--- a/src/core/dbus-cgroup.c
+++ b/src/core/dbus-cgroup.c
@@ -168,6 +168,8 @@ const sd_bus_vtable bus_cgroup_vtable[] = {
         SD_BUS_PROPERTY("MemoryLimit", "t", NULL, offsetof(CGroupContext, memory_limit), 0),
         SD_BUS_PROPERTY("DevicePolicy", "s", property_get_cgroup_device_policy, offsetof(CGroupContext, device_policy), 0),
         SD_BUS_PROPERTY("DeviceAllow", "a(ss)", property_get_device_allow, 0, 0),
+        SD_BUS_PROPERTY("TasksAccounting", "b", bus_property_get_bool, offsetof(CGroupContext, tasks_accounting), 0),
+        SD_BUS_PROPERTY("TasksMax", "t", NULL, offsetof(CGroupContext, tasks_max), 0),
         SD_BUS_VTABLE_END
 };
 
@@ -551,7 +553,11 @@ int bus_cgroup_set_property(
                 if (mode != UNIT_CHECK) {
                         c->memory_limit = limit;
                         u->cgroup_realized_mask &= ~CGROUP_MASK_MEMORY;
-                        unit_write_drop_in_private_format(u, mode, name, "%s=%" PRIu64, name, limit);
+
+                        if (limit == (uint64_t) -1)
+                                unit_write_drop_in_private(u, mode, name, "MemoryLimit=infinity");
+                        else
+                                unit_write_drop_in_private_format(u, mode, name, "MemoryLimit=%" PRIu64, limit);
                 }
 
                 return 1;
@@ -667,6 +673,39 @@ int bus_cgroup_set_property(
 
                 return 1;
 
+        } else if (streq(name, "TasksAccounting")) {
+                int b;
+
+                r = sd_bus_message_read(message, "b", &b);
+                if (r < 0)
+                        return r;
+
+                if (mode != UNIT_CHECK) {
+                        c->tasks_accounting = b;
+                        u->cgroup_realized_mask &= ~CGROUP_MASK_PIDS;
+                        unit_write_drop_in_private(u, mode, name, b ? "TasksAccounting=yes" : "TasksAccounting=no");
+                }
+
+                return 1;
+
+        } else if (streq(name, "TasksMax")) {
+                uint64_t limit;
+
+                r = sd_bus_message_read(message, "t", &limit);
+                if (r < 0)
+                        return r;
+
+                if (mode != UNIT_CHECK) {
+                        c->tasks_max = limit;
+                        u->cgroup_realized_mask &= ~CGROUP_MASK_PIDS;
+
+                        if (limit == (uint64_t) -1)
+                                unit_write_drop_in_private(u, mode, name, "TasksMax=infinity");
+                        else
+                                unit_write_drop_in_private_format(u, mode, name, "TasksMax=%" PRIu64, limit);
+                }
+
+                return 1;
         }
 
         if (u->transient && u->load_state == UNIT_STUB) {
diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index f9275ed935..f7e9795928 100644
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -736,6 +736,30 @@ static int property_get_current_memory(
         return sd_bus_message_append(reply, "t", sz);
 }
 
+static int property_get_current_tasks(
+                sd_bus *bus,
+                const char *path,
+                const char *interface,
+                const char *property,
+                sd_bus_message *reply,
+                void *userdata,
+                sd_bus_error *error) {
+
+        uint64_t cn = (uint64_t) -1;
+        Unit *u = userdata;
+        int r;
+
+        assert(bus);
+        assert(reply);
+        assert(u);
+
+        r = unit_get_tasks_current(u, &cn);
+        if (r < 0 && r != -ENODATA)
+                log_unit_warning_errno(u, r, "Failed to get pids.current attribute: %m");
+
+        return sd_bus_message_append(reply, "t", cn);
+}
+
 static int property_get_cpu_usage(
                 sd_bus *bus,
                 const char *path,
@@ -796,6 +820,7 @@ const sd_bus_vtable bus_unit_cgroup_vtable[] = {
         SD_BUS_PROPERTY("ControlGroup", "s", property_get_cgroup, 0, 0),
         SD_BUS_PROPERTY("MemoryCurrent", "t", property_get_current_memory, 0, 0),
         SD_BUS_PROPERTY("CPUUsageNSec", "t", property_get_cpu_usage, 0, 0),
+        SD_BUS_PROPERTY("TasksCurrent", "t", property_get_current_tasks, 0, 0),
         SD_BUS_VTABLE_END
 };
 
diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4
index edd55b9e45..e056fd863c 100644
--- a/src/core/load-fragment-gperf.gperf.m4
+++ b/src/core/load-fragment-gperf.gperf.m4
@@ -124,6 +124,8 @@ $1.StartupBlockIOWeight,         config_parse_blockio_weight,        0,
 $1.BlockIODeviceWeight,          config_parse_blockio_device_weight, 0,                             offsetof($1, cgroup_context)
 $1.BlockIOReadBandwidth,         config_parse_blockio_bandwidth,     0,                             offsetof($1, cgroup_context)
 $1.BlockIOWriteBandwidth,        config_parse_blockio_bandwidth,     0,                             offsetof($1, cgroup_context)
+$1.TasksAccounting,              config_parse_bool,                  0,                             offsetof($1, cgroup_context.tasks_accounting)
+$1.TasksMax,                     config_parse_tasks_max,             0,                             offsetof($1, cgroup_context)
 $1.Delegate,                     config_parse_bool,                  0,                             offsetof($1, cgroup_context.delegate)'
 )m4_dnl
 Unit.Description,                config_parse_unit_string_printf,    0,                             offsetof(Unit, description)
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 00cc6f7373..f7a8539910 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -2686,15 +2686,14 @@ int config_parse_memory_limit(
         uint64_t bytes;
         int r;
 
-        if (isempty(rvalue)) {
+        if (isempty(rvalue) || streq(rvalue, "infinity")) {
                 c->memory_limit = (uint64_t) -1;
                 return 0;
         }
 
         r = parse_size(rvalue, 1024, &bytes);
-        if (r < 0) {
-                log_syntax(unit, LOG_ERR, filename, line, EINVAL,
-                           "Memory limit '%s' invalid. Ignoring.", rvalue);
+        if (r < 0 || bytes < 1) {
+                log_syntax(unit, LOG_ERR, filename, line, EINVAL, "Memory limit '%s' invalid. Ignoring.", rvalue);
                 return 0;
         }
 
@@ -2702,6 +2701,36 @@ int config_parse_memory_limit(
         return 0;
 }
 
+int config_parse_tasks_max(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        CGroupContext *c = data;
+        uint64_t u;
+        int r;
+
+        if (isempty(rvalue) || streq(rvalue, "infinity")) {
+                c->tasks_max = (uint64_t) -1;
+                return 0;
+        }
+
+        r = safe_atou64(rvalue, &u);
+        if (r < 0 || u < 1) {
+                log_syntax(unit, LOG_ERR, filename, line, EINVAL, "Maximum tasks value '%s' invalid. Ignoring.", rvalue);
+                return 0;
+        }
+
+        return 0;
+}
+
 int config_parse_device_allow(
                 const char *unit,
                 const char *filename,
diff --git a/src/core/load-fragment.h b/src/core/load-fragment.h
index 1d128716c4..638b343a6e 100644
--- a/src/core/load-fragment.h
+++ b/src/core/load-fragment.h
@@ -84,6 +84,7 @@ int config_parse_environ(const char *unit, const char *filename, unsigned line,
 int config_parse_unit_slice(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_cpu_shares(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_memory_limit(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_tasks_max(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_device_policy(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_device_allow(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_blockio_weight(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
diff --git a/src/core/main.c b/src/core/main.c
index c9657505c3..200fe740da 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -114,6 +114,7 @@ static FILE* arg_serialization = NULL;
 static bool arg_default_cpu_accounting = false;
 static bool arg_default_blockio_accounting = false;
 static bool arg_default_memory_accounting = false;
+static bool arg_default_tasks_accounting = false;
 
 static void nop_handler(int sig) {}
 
@@ -676,6 +677,7 @@ static int parse_config_file(void) {
                 { "Manager", "DefaultCPUAccounting",      config_parse_bool,             0, &arg_default_cpu_accounting            },
                 { "Manager", "DefaultBlockIOAccounting",  config_parse_bool,             0, &arg_default_blockio_accounting        },
                 { "Manager", "DefaultMemoryAccounting",   config_parse_bool,             0, &arg_default_memory_accounting         },
+                { "Manager", "DefaultTasksAccounting",    config_parse_bool,             0, &arg_default_tasks_accounting          },
                 {}
         };
 
@@ -704,6 +706,7 @@ static void manager_set_defaults(Manager *m) {
         m->default_cpu_accounting = arg_default_cpu_accounting;
         m->default_blockio_accounting = arg_default_blockio_accounting;
         m->default_memory_accounting = arg_default_memory_accounting;
+        m->default_tasks_accounting = arg_default_tasks_accounting;
 
         manager_set_default_rlimits(m, arg_default_rlimit);
         manager_environment_add(m, NULL, arg_default_environment);
diff --git a/src/core/manager.h b/src/core/manager.h
index 9956cb7700..78a0e50a33 100644
--- a/src/core/manager.h
+++ b/src/core/manager.h
@@ -256,6 +256,7 @@ struct Manager {
         bool default_cpu_accounting;
         bool default_memory_accounting;
         bool default_blockio_accounting;
+        bool default_tasks_accounting;
 
         usec_t default_timer_accuracy_usec;
 
diff --git a/src/core/unit.c b/src/core/unit.c
index e40ea24be8..2ebfb09a7a 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -125,6 +125,7 @@ static void unit_init(Unit *u) {
                 cc->cpu_accounting = u->manager->default_cpu_accounting;
                 cc->blockio_accounting = u->manager->default_blockio_accounting;
                 cc->memory_accounting = u->manager->default_memory_accounting;
+                cc->tasks_accounting = u->manager->default_tasks_accounting;
         }
 
         ec = unit_get_exec_context(u);