On 7/22/20 1:49 AM, Baoquan He wrote:
> On 07/20/20 at 05:38pm, Mike Kravetz wrote:
>>> + if (count != h->max_huge_pages) {
>>> + char buf[32];
>>> +
>>> + string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
>>> + pr_warn("HugeTLB: %s %lu of page size %s failed. Only %s %lu hugepages.\n",
>>> + count > old_max ? "increasing" : "decreasing",
>>> + abs(count - old_max), buf,
>>> + count > old_max ? "increased" : "decreased",
>>> + abs(old_max - h->max_huge_pages));
>>> + }
>>> spin_unlock(&hugetlb_lock);
>>
>> I would prefer if we drop the lock before logging the message. That would
>> involve grabbing the value of h->max_huge_pages before dropping the lock.
>
> Do you think the below change is OK to you to move the message logging
> after lock dropping? If yes, I will repost with updated patches.
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 6a9b7556ce5b..b5aa32a13569 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -2661,7 +2661,7 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
> static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
> nodemask_t *nodes_allowed)
> {
> - unsigned long min_count, ret, old_max;
> + unsigned long min_count, ret, old_max, new_max;
> NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL);
>
> /*
> @@ -2780,7 +2780,10 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
> }
> out:
> h->max_huge_pages = persistent_huge_pages(h);
> - if (count != h->max_huge_pages) {
> + new_max = h->max_huge_pages;
> + spin_unlock(&hugetlb_lock);
> +
> + if (count != new_max) {
> char buf[32];
>
> string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
> @@ -2788,9 +2791,8 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
> count > old_max ? "increasing" : "decreasing",
> abs(count - old_max), buf,
> count > old_max ? "increased" : "decreased",
> - abs(old_max - h->max_huge_pages));
> + abs(old_max - new_max));
> }
> - spin_unlock(&hugetlb_lock);
>
> NODEMASK_FREE(node_alloc_noretry);
Yes, that looks better. Thank you.
--
Mike Kravetz
