[lxc-devel] [lxc/master] cgroups: unify cgfsng_{un}freeze()

[brauner on Github]

A non-text attachment was scrubbed...
Name: not available
Type: text/x-mailbox
Size: 364 bytes
Desc: not available
URL: <http://lists.linuxcontainers.org/pipermail/lxc-devel/attachments/20190902/b59495dc/attachment.bin>
-------------- next part --------------
From ee3a77758dfaafaf3a8dbf4ee25b66f5e04632b7 Mon Sep 17 00:00:00 2001
From: Christian Brauner <christian.brauner at ubuntu.com>
Date: Mon, 2 Sep 2019 23:51:19 +0200
Subject: [PATCH] cgroups: unify cgfsng_{un}freeze()

Signed-off-by: Christian Brauner <christian.brauner at ubuntu.com>
---
 src/lxc/cgroups/cgfsng.c | 93 ++++++++++++++++++++++++----------------
 1 file changed, 56 insertions(+), 37 deletions(-)

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index a5d6c01895..1e6a45cff2 100644
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -1995,40 +1995,38 @@ static bool poll_file_ready(int lfd)
 	return (pfd.revents & POLLIN);
 }
 
-__cgfsng_ops static bool cgfsng_freeze(struct cgroup_ops *ops)
+static bool cg_legacy_freeze(struct cgroup_ops *ops)
 {
-	int ret;
-	__do_close_prot_errno int fd = -EBADF;
-	__do_free char *events_file = NULL, *fullpath = NULL, *line = NULL;
-	__do_fclose FILE *f = NULL;
+	__do_free char *path = NULL;
 	struct hierarchy *h;
 
-	if (!ops->hierarchies)
-		return true;
+	h = get_hierarchy(ops, "freezer");
+	if (!h)
+		return false;
 
-	if (ops->cgroup_layout != CGROUP_LAYOUT_UNIFIED) {
-		h = get_hierarchy(ops, "freezer");
-		if (!h)
-			return false;
+	path = must_make_path(h->container_full_path, "freezer.state", NULL);
+	return lxc_write_to_file(path, "FROZEN", STRLITERALLEN("FROZEN"), false,
+				 0666) == 0;
+}
 
-		fullpath = must_make_path(h->container_full_path,
-					  "freezer.state", NULL);
-		return lxc_write_to_file(fullpath, "FROZEN",
-					 STRLITERALLEN("FROZEN"), false,
-					 0666) == 0;
-	}
+static bool cg_unified_freeze(struct cgroup_ops *ops)
+{
+	int ret;
+	__do_close_prot_errno int fd = -EBADF;
+	__do_free char *events_file = NULL, *path = NULL, *line = NULL;
+	__do_fclose FILE *f = NULL;
+	struct hierarchy *h;
 
 	h = ops->unified;
 	if (!h)
 		return false;
 
-	fullpath = must_make_path(h->container_full_path, "cgroup.freeze", NULL);
-	ret = lxc_write_to_file(fullpath, "1", 1, false, 0666);
+	path = must_make_path(h->container_full_path, "cgroup.freeze", NULL);
+	ret = lxc_write_to_file(path, "1", 1, false, 0666);
 	if (ret < 0)
 		return false;
 
-	events_file =
-	    must_make_path(h->container_full_path, "cgroup.events", NULL);
+	events_file = must_make_path(h->container_full_path, "cgroup.events", NULL);
 	fd = open(events_file, O_RDONLY | O_CLOEXEC);
 	if (fd < 0)
 		return false;
@@ -2052,32 +2050,53 @@ __cgfsng_ops static bool cgfsng_freeze(struct cgroup_ops *ops)
 	return false;
 }
 
-__cgfsng_ops static bool cgfsng_unfreeze(struct cgroup_ops *ops)
+__cgfsng_ops static bool cgfsng_freeze(struct cgroup_ops *ops)
 {
-	__do_free char *fullpath = NULL;
-	struct hierarchy *h;
-
 	if (!ops->hierarchies)
 		return true;
 
-	if (ops->cgroup_layout != CGROUP_LAYOUT_UNIFIED) {
-		h = get_hierarchy(ops, "freezer");
-		if (!h)
-			return false;
+	if (ops->cgroup_layout != CGROUP_LAYOUT_UNIFIED)
+		return cg_legacy_freeze(ops);
 
-		fullpath = must_make_path(h->container_full_path,
-					  "freezer.state", NULL);
-		return lxc_write_to_file(fullpath, "THAWED",
-					 STRLITERALLEN("THAWED"), false,
-					 0666) == 0;
-	}
+	return cg_unified_freeze(ops);
+}
+
+static bool cg_legacy_unfreeze(struct cgroup_ops *ops)
+{
+	__do_free char *path = NULL;
+	struct hierarchy *h;
+
+	h = get_hierarchy(ops, "freezer");
+	if (!h)
+		return false;
+
+	path = must_make_path(h->container_full_path, "freezer.state", NULL);
+	return lxc_write_to_file(path, "THAWED", STRLITERALLEN("THAWED"), false,
+				 0666) == 0;
+}
+
+static bool cg_unified_unfreeze(struct cgroup_ops *ops)
+{
+	__do_free char *path = NULL;
+	struct hierarchy *h;
 
 	h = ops->unified;
 	if (!h)
 		return false;
 
-	fullpath = must_make_path(h->container_full_path, "cgroup.freeze", NULL);
-	return lxc_write_to_file(fullpath, "0", 1, false, 0666) == 0;
+	path = must_make_path(h->container_full_path, "cgroup.freeze", NULL);
+	return lxc_write_to_file(path, "0", 1, false, 0666) == 0;
+}
+
+__cgfsng_ops static bool cgfsng_unfreeze(struct cgroup_ops *ops)
+{
+	if (!ops->hierarchies)
+		return true;
+
+	if (ops->cgroup_layout != CGROUP_LAYOUT_UNIFIED)
+		return cg_legacy_unfreeze(ops);
+
+	return cg_unified_unfreeze(ops);
 }
 
 __cgfsng_ops static const char *cgfsng_get_cgroup(struct cgroup_ops *ops,