On Fri, 19 May 2023 16:41:41 +0800 Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> wrote:
> any comments?
Have any of the regular CMA developers commented on a version of this?
I have a couple of little complaints:
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index bd6637f..19fb445 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -2225,10 +2225,16 @@ static unsigned long isolate_lru_folios(unsigned long nr_to_scan,
> unsigned long nr_skipped[MAX_NR_ZONES] = { 0, };
> unsigned long skipped = 0;
> unsigned long scan, total_scan, nr_pages;
> + bool cma_cap = true;
> + struct page *page;
> LIST_HEAD(folios_skipped);
>
> total_scan = 0;
> scan = 0;
> + if ((IS_ENABLED(CONFIG_CMA)) && !current_is_kswapd()
> + && (gfp_migratetype(sc->gfp_mask) != MIGRATE_MOVABLE))
> + cma_cap = false;
> +
A code comment above this alteration would be good. Tell the reader
why we're doing this.
> while (scan < nr_to_scan && !list_empty(src)) {
> struct list_head *move_to = src;
> struct folio *folio;
> @@ -2239,12 +2245,17 @@ static unsigned long isolate_lru_folios(unsigned long nr_to_scan,
> nr_pages = folio_nr_pages(folio);
> total_scan += nr_pages;
>
> - if (folio_zonenum(folio) > sc->reclaim_idx) {
> + page = &folio->page;
> +
> + if ((folio_zonenum(folio) > sc->reclaim_idx)
> +#ifdef CONFIG_CMA
> + || (get_pageblock_migratetype(page) == MIGRATE_CMA && !cma_cap)
> +#endif
> + ) {
> nr_skipped[folio_zonenum(folio)] += nr_pages;
> move_to = &folios_skipped;
> goto move;
> }
That's pretty ugly. Can we use IS_ENABLED(CONFIG_CMA) here to avoid
the ifdef?
