process-util: introduce proc_get_timerslack()

src/basic/process-util.c

@@ -2296,3 +2296,13 @@ int proc_set_comm(const char *comm) {
 int proc_set_nnp(void) {
         return prctl_safe(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 }
+
+nsec_t proc_get_timerslack(void) {
+        int r;
+
+        r = prctl_safe(PR_GET_TIMERSLACK, 0, 0, 0, 0);
+        if (r < 0)
+                return NSEC_INFINITY;
+
+        return r;
+}

src/basic/process-util.h

@@ -260,3 +260,4 @@ int prctl_safe(int op, unsigned long arg2, unsigned long arg3, unsigned long arg
 
 int proc_set_comm(const char *comm);
 int proc_set_nnp(void);
+nsec_t proc_get_timerslack(void);

src/core/dbus-manager.c

@@ -1,7 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include <linux/capability.h>
-#include <sys/prctl.h>
 #include <unistd.h>
 
 #include "alloc-util.h"
@@ -66,7 +65,7 @@ static BUS_DEFINE_PROPERTY_GET_GLOBAL(property_get_version, "s", GIT_VERSION);
 static BUS_DEFINE_PROPERTY_GET_GLOBAL(property_get_features, "s", systemd_features);
 static BUS_DEFINE_PROPERTY_GET_GLOBAL(property_get_architecture, "s", architecture_to_string(uname_architecture()));
 static BUS_DEFINE_PROPERTY_GET2(property_get_system_state, "s", Manager, manager_state, manager_state_to_string);
-static BUS_DEFINE_PROPERTY_GET_GLOBAL(property_get_timer_slack_nsec, "t", (uint64_t) prctl(PR_GET_TIMERSLACK));
+static BUS_DEFINE_PROPERTY_GET_GLOBAL(property_get_timer_slack_nsec, "t", proc_get_timerslack());
 static BUS_DEFINE_PROPERTY_GET_REF(property_get_hashmap_size, "u", Hashmap *, hashmap_size);
 static BUS_DEFINE_PROPERTY_GET_REF(property_get_set_size, "u", Set *, set_size);
 static BUS_DEFINE_PROPERTY_GET(property_get_default_timeout_abort_usec, "t", Manager, manager_default_timeout_abort_usec);

src/core/varlink-manager.c

@@ -1,7 +1,5 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <sys/prctl.h>
-
 #include "sd-bus.h"
 #include "sd-varlink.h"
 
@@ -18,6 +16,7 @@
 #include "manager.h"
 #include "path-util.h"
 #include "pidref.h"
+#include "process-util.h"
 #include "selinux-access.h"
 #include "set.h"
 #include "strv.h"
@@ -118,7 +117,7 @@ static int manager_context_build_json(sd_json_variant **ret, const char *name, v
                         JSON_BUILD_PAIR_FINITE_USEC("RuntimeWatchdogPreUSec", manager_get_watchdog(m, WATCHDOG_PRETIMEOUT)),
                         JSON_BUILD_PAIR_STRING_NON_EMPTY("RuntimeWatchdogPreGovernor", m->watchdog_pretimeout_governor),
                         JSON_BUILD_PAIR_STRING_NON_EMPTY("WatchdogDevice", watchdog_get_device()),
-                        JSON_BUILD_PAIR_FINITE_USEC("TimerSlackNSec", (uint64_t) prctl(PR_GET_TIMERSLACK)),
+                        JSON_BUILD_PAIR_FINITE_USEC("TimerSlackNSec", proc_get_timerslack()),
                         JSON_BUILD_PAIR_ENUM("DefaultOOMPolicy", oom_policy_to_string(m->defaults.oom_policy)),
                         SD_JSON_BUILD_PAIR_INTEGER("DefaultOOMScoreAdjust", m->defaults.oom_score_adjust),
                         SD_JSON_BUILD_PAIR_BOOLEAN("DefaultRestrictSUIDSGID", m->defaults.restrict_suid_sgid),