netprio_cgroup: use cgroup->id instead of cgroup_netprio_state->prioidx

With priomap expansion no longer depending on knowing max id
allocated, netprio_cgroup can use cgroup->id insted of cs->prioidx.
Drop prioidx alloc/free logic and convert all uses to cgroup->id.

* In cgrp_css_alloc(), parent->id test is moved above @cs allocation
  to simplify error path.

* In cgrp_css_free(), @cs assignment is made initialization.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Tested-and-Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tejun Heo 2012-11-22 07:32:47 -08:00
parent 4a6ee25c7e
commit 88d642fa2c
2 changed files with 15 additions and 61 deletions

View file

@ -27,7 +27,6 @@ struct netprio_map {
struct cgroup_netprio_state {
struct cgroup_subsys_state css;
u32 prioidx;
};
extern void sock_update_netprioidx(struct sock *sk, struct task_struct *task);
@ -36,13 +35,12 @@ extern void sock_update_netprioidx(struct sock *sk, struct task_struct *task);
static inline u32 task_netprioidx(struct task_struct *p)
{
struct cgroup_netprio_state *state;
struct cgroup_subsys_state *css;
u32 idx;
rcu_read_lock();
state = container_of(task_subsys_state(p, net_prio_subsys_id),
struct cgroup_netprio_state, css);
idx = state->prioidx;
css = task_subsys_state(p, net_prio_subsys_id);
idx = css->cgroup->id;
rcu_read_unlock();
return idx;
}
@ -57,8 +55,7 @@ static inline u32 task_netprioidx(struct task_struct *p)
rcu_read_lock();
css = task_subsys_state(p, net_prio_subsys_id);
if (css)
idx = container_of(css,
struct cgroup_netprio_state, css)->prioidx;
idx = css->cgroup->id;
rcu_read_unlock();
return idx;
}

View file

@ -28,10 +28,6 @@
#include <linux/fdtable.h>
#define PRIOMAP_MIN_SZ 128
#define PRIOIDX_SZ 128
static unsigned long prioidx_map[PRIOIDX_SZ];
static DEFINE_SPINLOCK(prioidx_map_lock);
static inline struct cgroup_netprio_state *cgrp_netprio_state(struct cgroup *cgrp)
{
@ -39,32 +35,6 @@ static inline struct cgroup_netprio_state *cgrp_netprio_state(struct cgroup *cgr
struct cgroup_netprio_state, css);
}
static int get_prioidx(u32 *prio)
{
unsigned long flags;
u32 prioidx;
spin_lock_irqsave(&prioidx_map_lock, flags);
prioidx = find_first_zero_bit(prioidx_map, sizeof(unsigned long) * PRIOIDX_SZ);
if (prioidx == sizeof(unsigned long) * PRIOIDX_SZ) {
spin_unlock_irqrestore(&prioidx_map_lock, flags);
return -ENOSPC;
}
set_bit(prioidx, prioidx_map);
spin_unlock_irqrestore(&prioidx_map_lock, flags);
*prio = prioidx;
return 0;
}
static void put_prioidx(u32 idx)
{
unsigned long flags;
spin_lock_irqsave(&prioidx_map_lock, flags);
clear_bit(idx, prioidx_map);
spin_unlock_irqrestore(&prioidx_map_lock, flags);
}
/*
* Extend @dev->priomap so that it's large enough to accomodate
* @target_idx. @dev->priomap.priomap_len > @target_idx after successful
@ -120,62 +90,50 @@ static int extend_netdev_table(struct net_device *dev, u32 target_idx)
static struct cgroup_subsys_state *cgrp_css_alloc(struct cgroup *cgrp)
{
struct cgroup_netprio_state *cs;
int ret = -EINVAL;
if (cgrp->parent && cgrp->parent->id)
return ERR_PTR(-EINVAL);
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs)
return ERR_PTR(-ENOMEM);
if (cgrp->parent && cgrp_netprio_state(cgrp->parent)->prioidx)
goto out;
ret = get_prioidx(&cs->prioidx);
if (ret < 0) {
pr_warn("No space in priority index array\n");
goto out;
}
return &cs->css;
out:
kfree(cs);
return ERR_PTR(ret);
}
static void cgrp_css_free(struct cgroup *cgrp)
{
struct cgroup_netprio_state *cs;
struct cgroup_netprio_state *cs = cgrp_netprio_state(cgrp);
struct net_device *dev;
struct netprio_map *map;
cs = cgrp_netprio_state(cgrp);
rtnl_lock();
for_each_netdev(&init_net, dev) {
map = rtnl_dereference(dev->priomap);
if (map && cs->prioidx < map->priomap_len)
map->priomap[cs->prioidx] = 0;
if (map && cgrp->id < map->priomap_len)
map->priomap[cgrp->id] = 0;
}
rtnl_unlock();
put_prioidx(cs->prioidx);
kfree(cs);
}
static u64 read_prioidx(struct cgroup *cgrp, struct cftype *cft)
{
return (u64)cgrp_netprio_state(cgrp)->prioidx;
return cgrp->id;
}
static int read_priomap(struct cgroup *cont, struct cftype *cft,
struct cgroup_map_cb *cb)
{
struct net_device *dev;
u32 prioidx = cgrp_netprio_state(cont)->prioidx;
u32 id = cont->id;
u32 priority;
struct netprio_map *map;
rcu_read_lock();
for_each_netdev_rcu(&init_net, dev) {
map = rcu_dereference(dev->priomap);
priority = (map && prioidx < map->priomap_len) ? map->priomap[prioidx] : 0;
priority = (map && id < map->priomap_len) ? map->priomap[id] : 0;
cb->fill(cb, dev->name, priority);
}
rcu_read_unlock();
@ -185,7 +143,6 @@ static int read_priomap(struct cgroup *cont, struct cftype *cft,
static int write_priomap(struct cgroup *cgrp, struct cftype *cft,
const char *buffer)
{
u32 prioidx = cgrp_netprio_state(cgrp)->prioidx;
char devname[IFNAMSIZ + 1];
struct net_device *dev;
struct netprio_map *map;
@ -201,13 +158,13 @@ static int write_priomap(struct cgroup *cgrp, struct cftype *cft,
rtnl_lock();
ret = extend_netdev_table(dev, prioidx);
ret = extend_netdev_table(dev, cgrp->id);
if (ret)
goto out_unlock;
map = rtnl_dereference(dev->priomap);
if (map)
map->priomap[prioidx] = prio;
map->priomap[cgrp->id] = prio;
out_unlock:
rtnl_unlock();
dev_put(dev);