Re: [PATCH v4 3/3] mm/mempolicy: introduce MPOL_WEIGHTED_INTERLEAVE for weighted interleaving

From: Gregory Price
Date: Wed Jan 31 2024 - 00:12:50 EST


On Tue, Jan 30, 2024 at 01:20:46PM -0500, Gregory Price wrote:
> + /* Continue allocating from most recent node and adjust the nr_pages */
> + node = me->il_prev;
> + weight = me->il_weight;
> + if (weight && node_isset(node, nodes)) {
> + node_pages = min(rem_pages, weight);
> + nr_allocated = __alloc_pages_bulk(gfp, node, NULL, node_pages,
> + NULL, page_array);
> + page_array += nr_allocated;
> + total_allocated += nr_allocated;
> + /* if that's all the pages, no need to interleave */
> + if (rem_pages < weight) {
> + /* stay on current node, adjust il_weight */
> + me->il_weight -= rem_pages;
> + return total_allocated;
> + } else if (rem_pages == weight) {
> + /* move to next node / weight */
> + me->il_prev = next_node_in(node, nodes);
> + me->il_weight = get_il_weight(next_node);

Sigh, I managed to miss a small update that killed next_node in favor of
operating directly on il_prev. Can you squash this fix into the patch?
Otherwise I can submit a separate patch.

~Gregory


diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 7cd92f4ec0d7..2c1aef8eab70 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2382,7 +2382,7 @@ static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp,
unsigned int weight_total = 0;
unsigned long rem_pages = nr_pages;
nodemask_t nodes;
- int nnodes, node, next_node;
+ int nnodes, node;
int resume_node = MAX_NUMNODES - 1;
u8 resume_weight = 0;
int prev_node;
@@ -2412,7 +2412,7 @@ static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp,
} else if (rem_pages == weight) {
/* move to next node / weight */
me->il_prev = next_node_in(node, nodes);
- me->il_weight = get_il_weight(next_node);
+ me->il_weight = get_il_weight(me->il_prev);
return total_allocated;
}
/* Otherwise we adjust remaining pages, continue from there */