Added -M option to lssubsys to show multiple mount points of hierarchies.

Now libcgroup is aware of hierarchies and all its mount points, let's
extend lssubsys to show them. The patch also renames few variables to be
descriptive, 'name' is not name of controller, it's list of controllers.

Now (and also with the patch, '-m' works the same):
$ lssubsys -m
cpuset,cpuacct /cgroup/cpu
memory /cgroup/memory

With the patch:
$ lssubsys -M
cpuset,cpuacct /cgroup/cpu
cpuset,cpuacct /cgroup/cpu2
memory /cgroup/memory

Signed-off-by: Jan Safranek <jsafrane@redhat.com>
Acked-by: Ivana Hutarova Varekova<varekova@redhat.com>

diff --git a/doc/man/lssubsys.1 b/doc/man/lssubsys.1
index 2555cb9a88c7fe9f7300d1f772e6ed905de3aced..81a5f995bbabc910ea2ed186b5b52f20fe09b6bc 100644 (file)
--- a/doc/man/lssubsys.1
+++ b/doc/man/lssubsys.1
@@ -7,9 +7,11 @@
 lssubsys \- list hierarchies containing given subsystem
 
 .SH SYNOPSIS
-\fBlssubsys\fR  [\fB-m|--mount-points\fR] [\fIcontroller\fR] [...]
+\fBlssubsys\fR  [\fB-m|--mount-points\fR] [\fB-M|--all-mount-points\fR]
+[\fIcontroller\fR] [...]
 .br
-\fBlssubsys\fR  [\fB-m|--mount-points\fR] [\fB-i|--hierarchies\fR] [\fB-a|--all\fR]
+\fBlssubsys\fR  [\fB-m|--mount-points\fR] [\fB-M|--all-mount-points\fR]
+[\fB-i|--hierarchies\fR] [\fB-a|--all\fR]
 .br
 \fBlssubsys\fR  [\fB-h|--help\fR]
 
@@ -27,7 +29,12 @@ list all mounted subsystems.
 
 .TP
 .B -m, --mount-points
-Display mount points.
+Display mount points. Only the first mount points of shown hierarchies are displayed.
+
+.TP
+.B -M, --all-mount-points
+Display mount points. All mount points of shown hierarchies are displayed, each on
+separate line.
 
 .TP
 .B -a, --all

diff --git a/src/tools/lssubsys.c b/src/tools/lssubsys.c
index f1225be0bfdb69a3745891734744934810dc7c7a..ad85e65843f54544b428a1af6f65b224474bba89 100644 (file)
--- a/src/tools/lssubsys.c
+++ b/src/tools/lssubsys.c
@@ -23,7 +23,8 @@ enum flag{
     FL_MOUNT = 1,      /* show the mount points */
     FL_LIST = 2,
     FL_ALL = 4,                /* show all subsystems - not mounted too */
-    FL_HIERARCHY = 8   /* show info about hierarchies */
+    FL_HIERARCHY = 8,  /* show info about hierarchies */
+    FL_MOUNT_ALL = 16  /* show all mount points of hierarchies */
 };
 
 typedef char cont_name_t[FILENAME_MAX];
@@ -42,25 +43,54 @@ static void usage(int status, const char *program_name)
                fprintf(stdout, "List information about given controller(s). "\
                        "If no controller is set list information about "\
                        "all mounted controllers.\n");
-               fprintf(stdout, "  -h, --help           Display this help\n");
-               fprintf(stdout, "  -m, --mount-points   Display mount points\n");
-               fprintf(stdout, "  -a, --all            "\
+               fprintf(stdout, "  -h, --help                   "\
+                       "Display this help\n");
+               fprintf(stdout, "  -m, --mount-points           "\
+                       "Display mount points\n");
+               fprintf(stdout, "  -M, --all-mount-points       "\
+                       "Display all mount points\n");
+               fprintf(stdout, "  -a, --all                    "\
                        "Display information about all controllers "\
                        "(including not mounted ones) \n");
-               fprintf(stdout, "  -i, --hierarchies    Display information "\
-                       "about hierarchies\n");
+               fprintf(stdout, "  -i, --hierarchies            "\
+                       "Display information about hierarchies\n");
        }
 }
 
+static int print_controller_mount(const char *controller, const char *clist,
+               const char *first_path, int flags)
+{
+       int ret = 0;
+       void *handle;
+       char path[FILENAME_MAX];
+
+       if (flags & FL_MOUNT_ALL) {
+               ret = cgroup_get_subsys_mount_point_begin(controller, &handle,
+                               path);
+               /* intentionally ignore error from above call */
+               while (ret == 0) {
+                       printf("%s %s\n", clist, path);
+                       ret = cgroup_get_subsys_mount_point_next(&handle, path);
+               }
+               if (ret == ECGEOF)
+                       ret = 0;
+               cgroup_get_subsys_mount_point_end(&handle);
+       } else {
+               printf("%s %s\n", clist, first_path);
+       }
+       return ret;
+}
+
 /* print data about input cont_name controller */
 static int print_controller(cont_name_t cont_name, int flags)
 {
        int ret = 0;
-       char name[FILENAME_MAX];
+       char controller_list[FILENAME_MAX];
        char path[FILENAME_MAX];
        void *handle;
        struct cgroup_mount_point controller;
        int output = 0;
+       char first_controller[FILENAME_MAX];
 
        ret = cgroup_get_controller_begin(&handle, &controller);
        if (ret != 0) {
@@ -70,15 +100,16 @@ static int print_controller(cont_name_t cont_name, int flags)
        }
 
        path[0] = '\0';
-       name[0] = '\0';
+       controller_list[0] = '\0';
 
        /* go through the list of controllers */
        while (ret == 0) {
                if (strcmp(path, controller.path) == 0) {
                        /* if it is still the same mount point */
-                       strncat(name, "," , FILENAME_MAX-strlen(name)-1);
-                       strncat(name, controller.name,
-                               FILENAME_MAX-strlen(name)-1);
+                       strncat(controller_list, "," ,
+                                       FILENAME_MAX-strlen(controller_list)-1);
+                       strncat(controller_list, controller.name,
+                               FILENAME_MAX-strlen(controller_list)-1);
                } else {
                        /*
                         * we got new mount point
@@ -86,21 +117,26 @@ static int print_controller(cont_name_t cont_name, int flags)
                         */
                        if (output) {
                                if ((flags &  FL_MOUNT) != 0)
-                                       printf("%s %s\n", name, path);
+                                       print_controller_mount(first_controller,
+                                                       controller_list, path,
+                                                       flags);
                                else
-                                       printf("%s\n", name);
+                                       printf("%s\n", controller_list);
                                if ((flags & FL_LIST) != 0) {
-                                       /* we succesfully finish printing */
+                                       /* we successfully finish printing */
                                        output = 0;
                                        break;
                                }
                        }
 
                        output = 0;
-                       strncpy(name, controller.name, FILENAME_MAX);
-                       name[FILENAME_MAX-1] = '\0';
+                       strncpy(controller_list, controller.name, FILENAME_MAX);
+                       controller_list[FILENAME_MAX-1] = '\0';
                        strncpy(path, controller.path, FILENAME_MAX);
                        path[FILENAME_MAX-1] = '\0';
+                       strncpy(first_controller, controller.name,
+                                       FILENAME_MAX);
+                       first_controller[FILENAME_MAX-1] = '\0';
                }
 
                /* set output flag */
@@ -114,9 +150,10 @@ static int print_controller(cont_name_t cont_name, int flags)
 
        if (output) {
                if ((flags &  FL_MOUNT) != 0)
-                       printf("%s %s\n", name, path);
+                       print_controller_mount(first_controller,
+                                       controller_list, path, flags);
                else
-                       printf("%s\n", name);
+                       printf("%s\n", controller_list);
                if ((flags & FL_LIST) != 0)
                        ret = 0;
        }
@@ -328,6 +365,7 @@ int main(int argc, char *argv[])
        static struct option options[] = {
                {"help", 0, 0, 'h'},
                {"mount-points", 0, 0, 'm'},
+               {"all-mount-points", 0, 0, 'M'},
                {"all", 0, 0, 'a'},
                {"hierarchies", 0, 0, 'i'},
                {0, 0, 0, 0}
@@ -337,7 +375,7 @@ int main(int argc, char *argv[])
                cont_name[i][0] = '\0';
 
        /* parse arguments */
-       while ((c = getopt_long(argc, argv, "mhai", options, NULL)) > 0) {
+       while ((c = getopt_long(argc, argv, "mMhai", options, NULL)) > 0) {
                switch (c) {
                case 'h':
                        usage(0, argv[0]);
@@ -345,6 +383,9 @@ int main(int argc, char *argv[])
                case 'm':
                        flags |= FL_MOUNT;
                        break;
+               case 'M':
+                       flags |= FL_MOUNT | FL_MOUNT_ALL;
+                       break;
                case 'a':
                        flags |= FL_ALL;
                        break;