Messages in this thread | | | Date | Mon, 12 Mar 2012 16:38:26 +0400 | From | Glauber Costa <> | Subject | Re: [PATCH v2 02/13] memcg: Kernel memory accounting infrastructure. |
| |
On 03/10/2012 12:39 AM, Suleiman Souhlal wrote: > +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM > +int > +memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, long long delta) > +{ > + struct res_counter *fail_res; > + struct mem_cgroup *_memcg; > + int may_oom, ret; > + > + may_oom = (gfp& __GFP_WAIT)&& (gfp& __GFP_FS)&& > + !(gfp& __GFP_NORETRY); > + > + ret = 0; > + > + _memcg = memcg; > + if (memcg&& !mem_cgroup_test_flag(memcg, > + MEMCG_INDEPENDENT_KMEM_LIMIT)) { > + ret = __mem_cgroup_try_charge(NULL, gfp, delta / PAGE_SIZE, > + &_memcg, may_oom); > + if (ret == -ENOMEM) > + return ret; > + } > + > + if (memcg&& _memcg == memcg) > + ret = res_counter_charge(&memcg->kmem, delta,&fail_res); > + > + return ret; > +} > + > +void Ok.
So I've spent most of the day today trying to come up with a way not to kill the whole performance we gain from consume_stock() by this res_counter_charge() to kmem afterwards...
You mentioned you want to still be able to bill to memcg->kmem mostly for debugging/display purposes. So we're surely not using all of the res_counter infrastructure (limiting, soft limits, etc)
I was thinking: Can't we have a percpu_counter that we use for this purpose when !kmem_independent ?
we may not even need to bloat the struct, since we can fold it into a union with struct res_counter kmem (which is bigger than a percpu counter anyway).
We just need to be a bit more careful not to allow kmem_independent to change when we already have charges to any of them (but we need to do it anyway)
| |