[PATCH] mm/mm_init.c: add debug messsge for dma zone

From: Haifeng Xu
Date: Wed Jun 07 2023 - 05:08:59 EST


If freesize is less than dma_reserve, print warning message to report
this case.

Signed-off-by: Haifeng Xu <haifeng.xu@xxxxxxxxxx>
---
mm/mm_init.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 232efac9a929..9a9d6a52471c 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -1561,9 +1561,14 @@ static void __init free_area_init_core(struct pglist_data *pgdat)
}

/* Account for reserved pages */
- if (j == 0 && freesize > dma_reserve) {
- freesize -= dma_reserve;
- pr_debug(" %s zone: %lu pages reserved\n", zone_names[0], dma_reserve);
+ if (j == 0) {
+ if (freesize >= dma_reserve) {
+ freesize -= dma_reserve;
+ pr_debug(" %s zone: %lu pages reserved\n",
+ zone_names[0], dma_reserve);
+ } else
+ pr_warn(" %s zone: %lu reserved pages exceeds freesize %lu\n",
+ zone_names[0], dma_reserve, freesize);
}

if (!is_highmem_idx(j))
--
2.25.1