On Fri, Apr 08, 2022 at 04:57:40AM +0000, Yosry Ahmed wrote:
> +static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf,
> + size_t nbytes, loff_t off)
> +{
> + struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
> + unsigned int nr_retries = MAX_RECLAIM_RETRIES;
> + unsigned long nr_to_reclaim, nr_reclaimed = 0;
> + int err;
> +
> + buf = strstrip(buf);
> + err = page_counter_memparse(buf, "", &nr_to_reclaim);
Is there a reason not to support "max"? Empty string seems odd to me
here.
> + if (err)
> + return err;
> +
> + while (nr_reclaimed < nr_to_reclaim) {
> + unsigned long reclaimed;
> +
> + if (signal_pending(current))
> + break;
I think this should be `return -EINTR;`
> +
> + reclaimed = try_to_free_mem_cgroup_pages(memcg,
> + nr_to_reclaim - nr_reclaimed,
> + GFP_KERNEL, true);
> +
> + if (!reclaimed && !nr_retries--)
> + break;
Here you can just `return -EAGAIN;`
> +
> + nr_reclaimed += reclaimed;
> + }
> +
> + return nr_reclaimed < nr_to_reclaim ? -EAGAIN : nbytes;
Then this can just be `return nbytes;`
I'm very much in favor of this new interface. Thanks for working on
it!
