> + /* try to charge */
> + ret = res_counter_charge(&mem->res, mem->borrow_unit);
> + if (!ret) { /* success */
> + *bwp += (mem->borrow_unit - size);
> + goto out;
> + }
> + }
> + spin_lock(&mem->res.lock);
> + ret = res_counter_charge_locked(&mem->res, size);
> + spin_unlock(&mem->res.lock);
although i don't know if it matters, this retrying of charge affects failcnt.
> +static void mem_cgroup_return_and_uncharge(struct mem_cgroup *mem, int size)
> +{
> + unsigned long flags;
> + int uncharge_size = 0;
> +
> + local_irq_save(flags);
> + if (mem->borrow_unit) {
> + int limit = mem->borrow_unit * 2;
> + int cpu;
> + s64 *bwp;
> + cpu = smp_processor_id();
> + bwp = &mem->stat.cpustat[cpu].count[MEM_CGROUP_STAT_BORROW];
> + *bwp += size;
> + if (*bwp > limit) {
> + uncharge_size = *bwp - mem->borrow_unit;
> + *bwp = mem->borrow_unit;
> + }
> + } else
> + uncharge_size = size;
> +
> + if (uncharge_size) {
> + spin_lock(&mem->res.lock);
> + res_counter_uncharge_locked(&mem->res, size);
s/size/uncharge_size/
> @@ -1109,12 +1202,29 @@ static u64 mem_throttle_read(struct cgro
> return (u64)mem->throttle.limit;
> }
>
> +static int mem_bulkratio_write(struct cgroup *cont, struct cftype *cft, u64
> val)
> +{
> + struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
> + int unit = val * PAGE_SIZE;
> + if (unit > (PAGE_SIZE << (MAX_ORDER/2)))
> + return -EINVAL;
> + mem->borrow_unit = unit;
> + return 0;
> +}
it seems unsafe with concurrent mem_cgroup_borrow_and_charge or
mem_cgroup_return_and_uncharge.
YAMAMOTO Takashi
_______________________________________________
Containers mailing list
[EMAIL PROTECTED]
https://lists.linux-foundation.org/mailman/listinfo/containers
_______________________________________________
Devel mailing list
Devel@openvz.org
https://openvz.org/mailman/listinfo/devel
