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rule=notspam policy=default score=0 phishscore=0 malwarescore=0 adultscore=0 suspectscore=0 spamscore=0 mlxlogscore=999 bulkscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2208160082 X-Proofpoint-GUID: 62xLIFfpr8JS2rO5KPTzC0h1AAlg656f X-Proofpoint-ORIG-GUID: 62xLIFfpr8JS2rO5KPTzC0h1AAlg656f Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/16/22 21:05, Miaohe Lin wrote: > There should be pages_per_huge_page(h) / pages_per_huge_page(target_hstate) > pages incremented for target_hstate->max_huge_pages when page is demoted. > Update max_huge_pages accordingly for consistency. > > Signed-off-by: Miaohe Lin > --- > mm/hugetlb.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index ea1c7bfa1cc3..e72052964fb5 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -3472,7 +3472,8 @@ static int demote_free_huge_page(struct hstate *h, struct page *page) > * based on pool changes for the demoted page. > */ > h->max_huge_pages--; > - target_hstate->max_huge_pages += pages_per_huge_page(h); > + target_hstate->max_huge_pages += > + pages_per_huge_page(h) / pages_per_huge_page(target_hstate); Thanks! That is indeed incorrect. However the miscalculation should not have any consequences. Correct? The value is used when initially populating the pools. It is never read and used again. It is written to in set_max_huge_pages if someone changes the number of hugetlb pages. I guess that is a long way of saying I am not sure why we care about trying to keep max_huge_pages up to date? I do not think it matters. I also thought, if we are going to adjust max_huge_pages here we may also want to adjust the node specific value: h->max_huge_pages_node[node]. There are a few other places where the global max_huge_pages is adjusted without adjusting the node specific value. The more I think about it, the more I think we should explore just eliminating any adjustment of this/these values after initially populating the pools. -- Mike Kravetz > > return rc; > } > -- > 2.23.0 >