X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=cgroup.c;h=86d4d5ea3b4331c1758561249b8583bce1e2ecc8;hp=29d89dd3e316c4ec8c6dfc385488129beb6f193a;hb=521da527743088a9bd2ab882f8b64799d49d5848;hpb=ed81ee199ec8f3cdfcdc78ff067a0397c3b02f5f

diff --git a/cgroup.c b/cgroup.c
index 29d89dd3..86d4d5ea 100644
--- a/cgroup.c
+++ b/cgroup.c
@@ -3,6 +3,9 @@
  */
 #include <stdio.h>
 #include <stdlib.h>
+#include <mntent.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include "fio.h"
 #include "flist.h"
 #include "cgroup.h"
@@ -13,16 +16,47 @@ static struct fio_mutex *lock;
 struct cgroup_member {
 	struct flist_head list;
 	char *root;
+	unsigned int cgroup_nodelete;
 };
 
-static void add_cgroup(const char *name, struct flist_head *clist)
+static char *find_cgroup_mnt(struct thread_data *td)
+{
+	char *mntpoint = NULL;
+	struct mntent *mnt, dummy;
+	char buf[256] = {0};
+	FILE *f;
+
+	f = setmntent("/proc/mounts", "r");
+	if (!f) {
+		td_verror(td, errno, "setmntent /proc/mounts");
+		return NULL;
+	}
+
+	while ((mnt = getmntent_r(f, &dummy, buf, sizeof(buf))) != NULL) {
+		if (!strcmp(mnt->mnt_type, "cgroup") &&
+		    strstr(mnt->mnt_opts, "blkio"))
+			break;
+	}
+
+	if (mnt)
+		mntpoint = smalloc_strdup(mnt->mnt_dir);
+	else
+		log_err("fio: cgroup blkio does not appear to be mounted\n");
+
+	endmntent(f);
+	return mntpoint;
+}
+
+static void add_cgroup(struct thread_data *td, const char *name,
+			struct flist_head *clist)
 {
 	struct cgroup_member *cm;
 
 	cm = smalloc(sizeof(*cm));
 	INIT_FLIST_HEAD(&cm->list);
 	cm->root = smalloc_strdup(name);
-
+	if (td->o.cgroup_nodelete)
+		cm->cgroup_nodelete = 1;
 	fio_mutex_down(lock);
 	flist_add_tail(&cm->list, clist);
 	fio_mutex_up(lock);
@@ -37,7 +71,8 @@ void cgroup_kill(struct flist_head *clist)
 
 	flist_for_each_safe(n, tmp, clist) {
 		cm = flist_entry(n, struct cgroup_member, list);
-		rmdir(cm->root);
+		if (!cm->cgroup_nodelete)
+			rmdir(cm->root);
 		flist_del(&cm->list);
 		sfree(cm->root);
 		sfree(cm);
@@ -46,26 +81,14 @@ void cgroup_kill(struct flist_head *clist)
 	fio_mutex_up(lock);
 }
 
-/*
- * Check if the given root appears valid
- */
-static int cgroup_check_fs(struct thread_data *td)
-{
-	struct stat sb;
-	char tmp[256];
-
-	sprintf(tmp, "%s/tasks", td->o.cgroup_root);
-	return stat(tmp, &sb);
-}
-
-static char *get_cgroup_root(struct thread_data *td)
+static char *get_cgroup_root(struct thread_data *td, char *mnt)
 {
 	char *str = malloc(64);
 
 	if (td->o.cgroup)
-		sprintf(str, "%s/%s", td->o.cgroup_root, td->o.cgroup);
+		sprintf(str, "%s%s%s", mnt, FIO_OS_PATH_SEPARATOR, td->o.cgroup);
 	else
-		sprintf(str, "%s/%s", td->o.cgroup_root, td->o.name);
+		sprintf(str, "%s%s%s", mnt, FIO_OS_PATH_SEPARATOR, td->o.name);
 
 	return str;
 }
@@ -76,8 +99,8 @@ static int write_int_to_file(struct thread_data *td, const char *path,
 {
 	char tmp[256];
 	FILE *f;
-	
-	sprintf(tmp, "%s/%s", path, filename);
+
+	sprintf(tmp, "%s%s%s", path, FIO_OS_PATH_SEPARATOR, filename);
 	f = fopen(tmp, "w");
 	if (!f) {
 		td_verror(td, errno, onerr);
@@ -100,34 +123,35 @@ static int cgroup_write_pid(struct thread_data *td, const char *root)
 /*
  * Move pid to root class
  */
-static int cgroup_del_pid(struct thread_data *td)
+static int cgroup_del_pid(struct thread_data *td, char *mnt)
 {
-	return cgroup_write_pid(td, td->o.cgroup_root);
+	return cgroup_write_pid(td, mnt);
 }
 
-int cgroup_setup(struct thread_data *td, struct flist_head *clist)
+int cgroup_setup(struct thread_data *td, struct flist_head *clist, char **mnt)
 {
 	char *root;
 
-	if (cgroup_check_fs(td)) {
-		log_err("fio: blkio cgroup mount point %s not valid\n",
-							td->o.cgroup_root);
-		return 1;
+	if (!*mnt) {
+		*mnt = find_cgroup_mnt(td);
+		if (!*mnt)
+			return 1;
 	}
 
 	/*
 	 * Create container, if it doesn't exist
 	 */
-	root = get_cgroup_root(td);
+	root = get_cgroup_root(td, *mnt);
 	if (mkdir(root, 0755) < 0) {
 		int __e = errno;
 
 		if (__e != EEXIST) {
 			td_verror(td, __e, "cgroup mkdir");
+			log_err("fio: path %s\n", root);
 			goto err;
 		}
 	} else
-		add_cgroup(root, clist);
+		add_cgroup(td, root, clist);
 
 	if (td->o.cgroup_weight) {
 		if (write_int_to_file(td, root, "blkio.weight",
@@ -146,19 +170,19 @@ err:
 	return 1;
 }
 
-void cgroup_shutdown(struct thread_data *td)
+void cgroup_shutdown(struct thread_data *td, char **mnt)
 {
-	if (cgroup_check_fs(td))
+	if (*mnt == NULL)
 		return;
 	if (!td->o.cgroup_weight && !td->o.cgroup)
 		return;
 
-	cgroup_del_pid(td);
+	cgroup_del_pid(td, *mnt);
 }
 
 static void fio_init cgroup_init(void)
 {
-	lock = fio_mutex_init(1);
+	lock = fio_mutex_init(FIO_MUTEX_UNLOCKED);
 }
 
 static void fio_exit cgroup_exit(void)