Add fopen_unlocked() wrapper

[thirdparty/systemd.git] / src / basic / cgroup-util.c

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 3f94602c8f0f585b9a1f8b05aa813ec5a1ae1d6b..11b4e3fce1a5777570225ce3bbd6d7d79994ba5a 100644 (file)
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -223,7 +223,7 @@ int cg_kill(
 
         _cleanup_set_free_ Set *allocated_set = NULL;
         bool done = false;
-        int r, ret = 0;
+        int r, ret = 0, ret_log_kill = 0;
         pid_t my_pid;
 
         assert(sig >= 0);
@@ -267,7 +267,7 @@ int cg_kill(
                                 continue;
 
                         if (log_kill)
-                                log_kill(pid, sig, userdata);
+                                ret_log_kill = log_kill(pid, sig, userdata);
 
                         /* If we haven't killed this process yet, kill
                          * it */
@@ -278,8 +278,12 @@ int cg_kill(
                                 if (flags & CGROUP_SIGCONT)
                                         (void) kill(pid, SIGCONT);
 
-                                if (ret == 0)
-                                        ret = 1;
+                                if (ret == 0) {
+                                        if (log_kill)
+                                                ret = ret_log_kill;
+                                        else
+                                                ret = 1;
+                                }
                         }
 
                         done = false;
@@ -872,7 +876,7 @@ int cg_set_access(
                 bool fatal;
         };
 
-        /* cgroupsv1, aka legacy/non-unified */
+        /* cgroup v1, aka legacy/non-unified */
         static const struct Attribute legacy_attributes[] = {
                 { "cgroup.procs",           true  },
                 { "tasks",                  false },
@@ -880,7 +884,7 @@ int cg_set_access(
                 {},
         };
 
-        /* cgroupsv2, aka unified */
+        /* cgroup v2, aka unified */
         static const struct Attribute unified_attributes[] = {
                 { "cgroup.procs",           true  },
                 { "cgroup.subtree_control", true  },
@@ -1012,11 +1016,11 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
         }
 
         fs = procfs_file_alloca(pid, "cgroup");
-        f = fopen(fs, "re");
-        if (!f)
-                return errno == ENOENT ? -ESRCH : -errno;
-
-        (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
+        r = fopen_unlocked(fs, "re", &f);
+        if (r == -ENOENT)
+                return -ESRCH;
+        if (r < 0)
+                return r;
 
         for (;;) {
                 _cleanup_free_ char *line = NULL;
@@ -1852,9 +1856,7 @@ char *cg_escape(const char *p) {
          * needs free()! */
 
         if (IN_SET(p[0], 0, '_', '.') ||
-            streq(p, "notify_on_release") ||
-            streq(p, "release_agent") ||
-            streq(p, "tasks") ||
+            STR_IN_SET(p, "notify_on_release", "release_agent", "tasks") ||
             startswith(p, "cgroup."))
                 need_prefix = true;
         else {
@@ -2041,7 +2043,7 @@ int cg_get_keyed_attribute(
         char **v;
         int r;
 
-        /* Reads one or more fields of a cgroupsv2 keyed attribute file. The 'keys' parameter should be an strv with
+        /* Reads one or more fields of a cgroup v2 keyed attribute file. The 'keys' parameter should be an strv with
          * all keys to retrieve. The 'ret_values' parameter should be passed as string size with the same number of
          * entries as 'keys'. On success each entry will be set to the value of the matching key.
          *
@@ -2440,17 +2442,13 @@ int cg_kernel_controllers(Set **ret) {
         if (!controllers)
                 return -ENOMEM;
 
-        f = fopen("/proc/cgroups", "re");
-        if (!f) {
-                if (errno == ENOENT) {
-                        *ret = NULL;
-                        return 0;
-                }
-
-                return -errno;
+        r = fopen_unlocked("/proc/cgroups", "re", &f);
+        if (r == -ENOENT) {
+                *ret = NULL;
+                return 0;
         }
-
-        (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
+        if (r < 0)
+                return r;
 
         /* Ignore the header line */
         (void) read_line(f, (size_t) -1, NULL);
@@ -2493,7 +2491,7 @@ int cg_kernel_controllers(Set **ret) {
 
 static thread_local CGroupUnified unified_cache = CGROUP_UNIFIED_UNKNOWN;
 
-/* The hybrid mode was initially implemented in v232 and simply mounted cgroup v2 on /sys/fs/cgroup/systemd.  This
+/* The hybrid mode was initially implemented in v232 and simply mounted cgroup2 on /sys/fs/cgroup/systemd.  This
  * unfortunately broke other tools (such as docker) which expected the v1 "name=systemd" hierarchy on
  * /sys/fs/cgroup/systemd.  From v233 and on, the hybrid mode mountnbs v2 on /sys/fs/cgroup/unified and maintains
  * "name=systemd" hierarchy on /sys/fs/cgroup/systemd for compatibility with other tools.
@@ -2708,6 +2706,7 @@ bool cg_is_unified_wanted(void) {
         int r;
         bool b;
         const bool is_default = DEFAULT_HIERARCHY == CGROUP_UNIFIED_ALL;
+        _cleanup_free_ char *c = NULL;
 
         /* If we have a cached value, return that. */
         if (wanted >= 0)
@@ -2718,11 +2717,19 @@ bool cg_is_unified_wanted(void) {
         if (cg_unified_flush() >= 0)
                 return (wanted = unified_cache >= CGROUP_UNIFIED_ALL);
 
-        /* Otherwise, let's see what the kernel command line has to say.
-         * Since checking is expensive, cache a non-error result. */
+        /* If we were explicitly passed systemd.unified_cgroup_hierarchy,
+         * respect that. */
         r = proc_cmdline_get_bool("systemd.unified_cgroup_hierarchy", &b);
+        if (r > 0)
+                return (wanted = b);
+
+        /* If we passed cgroup_no_v1=all with no other instructions, it seems
+         * highly unlikely that we want to use hybrid or legacy hierarchy. */
+        r = proc_cmdline_get_key("cgroup_no_v1", 0, &c);
+        if (r > 0 && streq_ptr(c, "all"))
+                return (wanted = true);
 
-        return (wanted = r > 0 ? b : is_default);
+        return (wanted = is_default);
 }
 
 bool cg_is_legacy_wanted(void) {
@@ -2732,13 +2739,13 @@ bool cg_is_legacy_wanted(void) {
         if (wanted >= 0)
                 return wanted;
 
-        /* Check if we have cgroups2 already mounted. */
+        /* Check if we have cgroup v2 already mounted. */
         if (cg_unified_flush() >= 0 &&
             unified_cache == CGROUP_UNIFIED_ALL)
                 return (wanted = false);
 
         /* Otherwise, assume that at least partial legacy is wanted,
-         * since cgroups2 should already be mounted at this point. */
+         * since cgroup v2 should already be mounted at this point. */
         return (wanted = true);
 }
 
@@ -2860,7 +2867,7 @@ bool fd_is_cgroup_fs(int fd) {
         return is_cgroup_fs(&s);
 }
 
-static const char *cgroup_controller_table[_CGROUP_CONTROLLER_MAX] = {
+static const char *const cgroup_controller_table[_CGROUP_CONTROLLER_MAX] = {
         [CGROUP_CONTROLLER_CPU] = "cpu",
         [CGROUP_CONTROLLER_CPUACCT] = "cpuacct",
         [CGROUP_CONTROLLER_IO] = "io",