Better support for setting up and removing private cgroups

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/cgroup.c b/cgroup.c
index 548740a08e9bd0f12741def199e40dc8843cc50d..b0c7ea2003ac1a78937c45d562a57809fdd4e739 100644 (file)
--- a/cgroup.c
+++ b/cgroup.c
@@ -4,7 +4,59 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include "fio.h"
+#include "flist.h"
 #include "cgroup.h"
+#include "smalloc.h"
+
+static struct flist_head *cgroup_list;
+static struct fio_mutex *lock;
+
+struct cgroup_member {
+       struct flist_head list;
+       char *root;
+};
+
+static void add_cgroup(const char *name)
+{
+       struct cgroup_member *cm;
+
+       cm = smalloc(sizeof(*cm));
+       INIT_FLIST_HEAD(&cm->list);
+       cm->root = smalloc_strdup(name);
+
+       fio_mutex_down(lock);
+
+       if (!cgroup_list) {
+               cgroup_list = smalloc(sizeof(struct flist_head));
+               INIT_FLIST_HEAD(cgroup_list);
+       }
+
+       flist_add_tail(&cm->list, cgroup_list);
+       fio_mutex_up(lock);
+}
+
+void cgroup_kill(void)
+{
+       struct flist_head *n, *tmp;
+       struct cgroup_member *cm;
+
+       fio_mutex_down(lock);
+       if (!cgroup_list)
+               goto out;
+
+       flist_for_each_safe(n, tmp, cgroup_list) {
+               cm = flist_entry(n, struct cgroup_member, list);
+               rmdir(cm->root);
+               flist_del(&cm->list);
+               sfree(cm->root);
+               sfree(cm);
+       }
+
+       sfree(cgroup_list);
+       cgroup_list = NULL;
+out:
+       fio_mutex_up(lock);
+}
 
 /*
  * Check if the given root appears valid
@@ -40,7 +92,6 @@ static int cgroup_add_pid(struct thread_data *td)
 
        root = get_cgroup_root(td);
        sprintf(tmp, "%s/tasks", root);
-
        f = fopen(tmp, "w");
        if (!f) {
                td_verror(td, errno, "cgroup open tasks");
@@ -97,17 +148,20 @@ int cgroup_setup(struct thread_data *td)
                        return 1;
                }
        } else
-               td->o.cgroup_was_created = 1;
+               add_cgroup(root);
 
-       sprintf(tmp, "%s/blkio.weight", root);
-       f = fopen(tmp, "w");
-       if (!f) {
-               td_verror(td, errno, "cgroup open weight");
-               return 1;
+       if (td->o.cgroup_weight) {
+               sprintf(tmp, "%s/blkio.weight", root);
+               f = fopen(tmp, "w");
+               if (!f) {
+                       td_verror(td, errno, "cgroup open weight");
+                       return 1;
+               }
+
+               fprintf(f, "%d", td->o.cgroup_weight);
+               fclose(f);
        }
 
-       fprintf(f, "%d", td->o.cgroup_weight);
-       fclose(f);
        free(root);
 
        if (cgroup_add_pid(td))
@@ -120,16 +174,19 @@ void cgroup_shutdown(struct thread_data *td)
 {
        if (cgroup_check_fs(td))
                return;
-       if (!td->o.cgroup_weight)
+       if (!td->o.cgroup_weight && td->o.cgroup)
                return;
 
        cgroup_del_pid(td);
+}
 
-       if (td->o.cgroup_was_created) {
-               char *root;
 
-               root = get_cgroup_root(td);
-               rmdir(root);
-               free(root);
-       }
+static void fio_init cgroup_init(void)
+{
+       lock = fio_mutex_init(1);
+}
+
+static void fio_exit cgroup_exit(void)
+{
+       fio_mutex_remove(lock);
 }

diff --git a/cgroup.h b/cgroup.h
index 65fa3ad128ce5d036d74a0f9ca5e80f26deb3c1b..1c67ba80ab36ee1e67f9b454e3d9ed8d62875e53 100644 (file)
--- a/cgroup.h
+++ b/cgroup.h
@@ -6,6 +6,8 @@
 int cgroup_setup(struct thread_data *td);
 void cgroup_shutdown(struct thread_data *td);
 
+void cgroup_kill(void);
+
 #else
 
 static inline int cgroup_setup(struct thread_data *td)
@@ -18,5 +20,9 @@ static inline void cgroup_shutdown(struct thread_data *td)
 {
 }
 
+void cgroup_kill(void)
+{
+}
+
 #endif
 #endif

diff --git a/fio.c b/fio.c
index 4bbab5af9a12e9c0d00fa559bdddb94107b42f77..a18ca1b63f185fdca01d2ae677cd669fdefb4e58 100644 (file)
--- a/fio.c
+++ b/fio.c
@@ -1668,6 +1668,8 @@ int main(int argc, char *argv[])
                }
        }
 
+       cgroup_kill();
+
        fio_mutex_remove(startup_mutex);
        fio_mutex_remove(writeout_mutex);
        return exit_value;

diff --git a/fio.h b/fio.h
index aa5124cd03a805d9158391131d3e1788c1f4b9e9..17aeaadae07cedf53cd137ed23475bf2b622e86d 100644 (file)
--- a/fio.h
+++ b/fio.h
@@ -278,7 +278,6 @@ struct thread_options {
        char *cgroup_root;
        char *cgroup;
        unsigned int cgroup_weight;
-       unsigned int cgroup_was_created;
 };
 
 #define FIO_VERROR_SIZE        128