On Sat, 24 Sep 2011 10:30:42 -0300 Glauber Costa <glommer@xxxxxxxxxxxxx> wrote: > On 09/22/2011 03:01 AM, Greg Thelen wrote: > > On Sun, Sep 18, 2011 at 5:56 PM, Glauber Costa<glommer@xxxxxxxxxxxxx> wrote: > >> +static inline bool mem_cgroup_is_root(struct mem_cgroup *mem) > >> +{ > >> + return (mem == root_mem_cgroup); > >> +} > >> + > > > > Why are you adding a copy of mem_cgroup_is_root(). I see one already > > in v3.0. Was it deleted in a previous patch? > > Already answered by another good samaritan. > > >> +static int tcp_write_maxmem(struct cgroup *cgrp, struct cftype *cft, u64 val) > >> +{ > >> + struct mem_cgroup *sg = mem_cgroup_from_cont(cgrp); > >> + struct mem_cgroup *parent = parent_mem_cgroup(sg); > >> + struct net *net = current->nsproxy->net_ns; > >> + int i; > >> + > >> + if (!cgroup_lock_live_group(cgrp)) > >> + return -ENODEV; > > > > Why is cgroup_lock_live_cgroup() needed here? Does it protect updates > > to sg->tcp_prot_mem[*]? > > > >> +static u64 tcp_read_maxmem(struct cgroup *cgrp, struct cftype *cft) > >> +{ > >> + struct mem_cgroup *sg = mem_cgroup_from_cont(cgrp); > >> + u64 ret; > >> + > >> + if (!cgroup_lock_live_group(cgrp)) > >> + return -ENODEV; > > > > Why is cgroup_lock_live_cgroup() needed here? Does it protect updates > > to sg->tcp_max_memory? > > No, that is not my understanding. My understanding is this lock is > needed to protect against the cgroup just disappearing under our nose. > Hm. reference count of dentry for cgroup isn't enough ? Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>