Re: [PATCH 03/10] netprio: use css ID instead of cgroup ID

From: Neil Horman
Date: Tue Nov 05 2019 - 08:28:05 EST


On Mon, Nov 04, 2019 at 03:59:37PM -0800, Tejun Heo wrote:
> netprio uses cgroup ID to index the priority mapping table. This is
> currently okay as cgroup IDs are allocated using idr and packed.
> However, cgroup IDs will be changed to use full 64bit range and won't
> be packed making this impractical. netprio doesn't care what type of
> IDs it uses as long as they can identify the controller instances and
> are packed. Let's switch to css IDs instead of cgroup IDs.
>
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Neil Horman <nhorman@xxxxxxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> Hello,
>
> This is to prepare for kernfs 64bit ino support. It'd be best to
> route this with the rest of kernfs patchset.
>
> Thanks.
>
> include/net/netprio_cgroup.h | 2 +-
> net/core/netprio_cgroup.c | 8 ++++----
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/include/net/netprio_cgroup.h b/include/net/netprio_cgroup.h
> index cfc9441ef074..dec7522b6ce1 100644
> --- a/include/net/netprio_cgroup.h
> +++ b/include/net/netprio_cgroup.h
> @@ -26,7 +26,7 @@ static inline u32 task_netprioidx(struct task_struct *p)
>
> rcu_read_lock();
> css = task_css(p, net_prio_cgrp_id);
> - idx = css->cgroup->id;
> + idx = css->id;
> rcu_read_unlock();
> return idx;
> }
> diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
> index 256b7954b720..8881dd943dd0 100644
> --- a/net/core/netprio_cgroup.c
> +++ b/net/core/netprio_cgroup.c
> @@ -93,7 +93,7 @@ static int extend_netdev_table(struct net_device *dev, u32 target_idx)
> static u32 netprio_prio(struct cgroup_subsys_state *css, struct net_device *dev)
> {
> struct netprio_map *map = rcu_dereference_rtnl(dev->priomap);
> - int id = css->cgroup->id;
> + int id = css->id;
>
> if (map && id < map->priomap_len)
> return map->priomap[id];
> @@ -113,7 +113,7 @@ static int netprio_set_prio(struct cgroup_subsys_state *css,
> struct net_device *dev, u32 prio)
> {
> struct netprio_map *map;
> - int id = css->cgroup->id;
> + int id = css->id;
> int ret;
>
> /* avoid extending priomap for zero writes */
> @@ -177,7 +177,7 @@ static void cgrp_css_free(struct cgroup_subsys_state *css)
>
> static u64 read_prioidx(struct cgroup_subsys_state *css, struct cftype *cft)
> {
> - return css->cgroup->id;
> + return css->id;
> }
>
> static int read_priomap(struct seq_file *sf, void *v)
> @@ -237,7 +237,7 @@ static void net_prio_attach(struct cgroup_taskset *tset)
> struct cgroup_subsys_state *css;
>
> cgroup_taskset_for_each(p, css, tset) {
> - void *v = (void *)(unsigned long)css->cgroup->id;
> + void *v = (void *)(unsigned long)css->id;
>
> task_lock(p);
> iterate_fd(p->files, 0, update_netprio, v);
> --
> 2.17.1
>
>
Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx>