On Mon, Dec 13, 2021 at 04:57:06PM +0800, Mark-PK Tsai wrote:
Subject: [PATCH 5.4 1/5] memblock: free_unused_memmap: use pageblock units instead of MAX_ORDER
I'd replace memblock: with arm: in the subject. I believe it's clearer this way.
The same applies for the second patch in the series and for 5.10 posting.
From: Mike Rapoport rppt@linux.ibm.com
commit e2a86800d58639b3acde7eaeb9eb393dca066e08 upstream.
The code that frees unused memory map uses rounds start and end of the holes that are freed to MAX_ORDER_NR_PAGES to preserve continuity of the memory map for MAX_ORDER regions.
Lots of core memory management functionality relies on homogeneity of the memory map within each pageblock which size may differ from MAX_ORDER in certain configurations.
Although currently, for the architectures that use free_unused_memmap(), pageblock_order and MAX_ORDER are equivalent, it is cleaner to have common notation thought mm code.
Replace MAX_ORDER_NR_PAGES with pageblock_nr_pages and update the comments to make it more clear why the alignment to pageblock boundaries is required.
Signed-off-by: Mike Rapoport rppt@linux.ibm.com Tested-by: Tony Lindgren tony@atomide.com Link: https://lore.kernel.org/lkml/20210630071211.21011-1-rppt@kernel.org/ [backport upstream modification in mm/memblock.c to arch/arm/mm/init.c] Signed-off-by: Mark-PK Tsai mark-pk.tsai@mediatek.com
arch/arm/mm/init.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 7ea4d3b43444..6905dd8bc03f 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -381,11 +381,11 @@ static void __init free_unused_memmap(void) ALIGN(prev_end, PAGES_PER_SECTION)); #else /*
* Align down here since the VM subsystem insists that the* memmap entries are valid from the bank start aligned to* MAX_ORDER_NR_PAGES.
* Align down here since many operations in VM subsystem* presume that there are no holes in the memory map inside* a pageblock
start = round_down(start, MAX_ORDER_NR_PAGES);
start = round_down(start, pageblock_nr_pages);#endif /* * If we had a previous bank, and there is a space @@ -395,12 +395,12 @@ static void __init free_unused_memmap(void) free_memmap(prev_end, start); /*
* Align up here since the VM subsystem insists that the* memmap entries are valid from the bank end aligned to* MAX_ORDER_NR_PAGES.
* Align up here since many operations in VM subsystem* presume that there are no holes in the memory map inside* a pageblock
MAX_ORDER_NR_PAGES);
pageblock_nr_pages);#ifdef CONFIG_SPARSEMEM
2.18.0