[PATCH v10 2/4] cgroups: replace explicit ss_mask checking with for_each_subsys_which

Aleksa Sarai
2015-04-19T12:22:32Z

Replace the explicit checking against ss_masks inside a for_each_subsys
block with for_each_subsys_which(ss_mask, ...), to take advantage of the
more readable macro.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
---
kernel/cgroup.c | 42 ++++++++++++++----------------------------
1 file changed, 14 insertions(+), 28 deletions(-)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 1d69a085..abd491f 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1099,9 +1099,8 @@ static unsigned int cgroup_calc_child_subsys_mask(struct cgroup *cgrp,
while (true) {
unsigned int new_ss_mask = cur_ss_mask;

- for_each_subsys(ss, ssid)
- if (cur_ss_mask & (1 << ssid))
- new_ss_mask |= ss->depends_on;
+ for_each_subsys_which(cur_ss_mask, ss, ssid)
+ new_ss_mask |= ss->depends_on;

/*
* Mask out subsystems which aren't available. This can
@@ -1238,10 +1237,7 @@ static int rebind_subsystems(struct cgroup_root *dst_root, unsigned int ss_mask)

lockdep_assert_held(&cgroup_mutex);

- for_each_subsys(ss, ssid) {
- if (!(ss_mask & (1 << ssid)))
- continue;
-
+ for_each_subsys_which(ss_mask, ss, ssid) {
/* if @ss has non-root csses attached to it, can't move */
if (css_next_child(NULL, cgroup_css(&ss->root->cgrp, ss)))
return -EBUSY;
@@ -1278,18 +1274,14 @@ static int rebind_subsystems(struct cgroup_root *dst_root, unsigned int ss_mask)
* Nothing can fail from this point on. Remove files for the
* removed subsystems and rebind each subsystem.
*/
- for_each_subsys(ss, ssid)
- if (ss_mask & (1 << ssid))
- cgroup_clear_dir(&ss->root->cgrp, 1 << ssid);
+ for_each_subsys_which(ss_mask, ss, ssid)
+ cgroup_clear_dir(&ss->root->cgrp, 1 << ssid);

- for_each_subsys(ss, ssid) {
+ for_each_subsys_which(ss_mask, ss, ssid) {
struct cgroup_root *src_root;
struct cgroup_subsys_state *css;
struct css_set *cset;

- if (!(ss_mask & (1 << ssid)))
- continue;
-
src_root = ss->root;
css = cgroup_css(&src_root->cgrp, ss);

@@ -2563,13 +2555,11 @@ static void cgroup_print_ss_mask(struct seq_file *seq, unsigned int ss_mask)
bool printed = false;
int ssid;

- for_each_subsys(ss, ssid) {
- if (ss_mask & (1 << ssid)) {
- if (printed)
- seq_putc(seq, ' ');
- seq_printf(seq, "%s", ss->name);
- printed = true;
- }
+ for_each_subsys_which(ss_mask, ss, ssid) {
+ if (printed)
+ seq_putc(seq, ' ');
+ seq_printf(seq, "%s", ss->name);
+ printed = true;
}
if (printed)
seq_putc(seq, '\n');
@@ -2719,9 +2709,8 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
while ((tok = strsep(&buf, " "))) {
if (tok[0] == '\0')
continue;
- for_each_subsys(ss, ssid) {
- if (ss->disabled || strcmp(tok + 1, ss->name) ||
- ((1 << ss->id) & cgrp_dfl_root_inhibit_ss_mask))
+ for_each_subsys_which(~cgrp_dfl_root_inhibit_ss_mask, ss, ssid) {
+ if (ss->disabled || strcmp(tok + 1, ss->name))
continue;

if (*tok == '+') {
@@ -2808,10 +2797,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
* still around. In such cases, wait till it's gone using
* offline_waitq.
*/
- for_each_subsys(ss, ssid) {
- if (!(css_enable & (1 << ssid)))
- continue;
-
+ for_each_subsys_which(css_enable, ss, ssid) {
cgroup_for_each_live_child(child, cgrp) {
DEFINE_WAIT(wait);

--
2.3.5