[PATCH v2] mm/numa: Use SZ_1M macro to denote bytes to MB conversion

[PATCH v2] mm/numa: Use SZ_1M macro to denote bytes to MB conversion

[pratyush.brahma]

From: Pratyush Brahma <pratyush.brahma@oss.qualcomm.com>

Replace the manual bitwise conversion of bytes to MB with
SZ_1M macro, a standard macro used within the mm subsystem,
to improve readability.

Signed-off-by: Pratyush Brahma <pratyush.brahma@oss.qualcomm.com>
---
Changes in v2:
- Replaced the implementations in numa_emulation.c and memblock.c as
  well as per Mike's recommendation.
- Link to v1: https://lore.kernel.org/r/20250819-numa-memblks-refac-v1-1-936b4fd35000@oss.qualcomm.com
---
 mm/memblock.c       | 4 ++--
 mm/numa_emulation.c | 4 ++--
 mm/numa_memblks.c   | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index 154f1d73b61f2234efe61c5cce5105be160d0041..8a0ed3074af4b4dacb87e45f3fecaeb6b3222fcf 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -780,9 +780,9 @@ bool __init_memblock memblock_validate_numa_coverage(unsigned long threshold_byt
 	}
 
 	if ((nr_pages << PAGE_SHIFT) > threshold_bytes) {
-		mem_size_mb = memblock_phys_mem_size() >> 20;
+		mem_size_mb = memblock_phys_mem_size() / SZ_1M;
 		pr_err("NUMA: no nodes coverage for %luMB of %luMB RAM\n",
-		       (nr_pages << PAGE_SHIFT) >> 20, mem_size_mb);
+		       (nr_pages << PAGE_SHIFT) / SZ_1M, mem_size_mb);
 		return false;
 	}
 
diff --git a/mm/numa_emulation.c b/mm/numa_emulation.c
index 9d55679d99ceea9807d41840cf097eb449afaf8e..703c8fa05048019317bc2a011d7b928884ddc934 100644
--- a/mm/numa_emulation.c
+++ b/mm/numa_emulation.c
@@ -73,7 +73,7 @@ static int __init emu_setup_memblk(struct numa_meminfo *ei,
 	}
 
 	printk(KERN_INFO "Faking node %d at [mem %#018Lx-%#018Lx] (%LuMB)\n",
-	       nid, eb->start, eb->end - 1, (eb->end - eb->start) >> 20);
+	       nid, eb->start, eb->end - 1, (eb->end - eb->start) / SZ_1M);
 	return 0;
 }
 
@@ -264,7 +264,7 @@ static int __init split_nodes_size_interleave_uniform(struct numa_meminfo *ei,
 	min_size = ALIGN(max(min_size, FAKE_NODE_MIN_SIZE), FAKE_NODE_MIN_SIZE);
 	if (size < min_size) {
 		pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
-			size >> 20, min_size >> 20);
+			size / SZ_1M, min_size / SZ_1M);
 		size = min_size;
 	}
 	size = ALIGN_DOWN(size, FAKE_NODE_MIN_SIZE);
diff --git a/mm/numa_memblks.c b/mm/numa_memblks.c
index 541a99c4071a67e5b0ef66f4136dee268a880003..a47aa262a33366337c38ccc7c7064da818523dd2 100644
--- a/mm/numa_memblks.c
+++ b/mm/numa_memblks.c
@@ -427,9 +427,9 @@ static int __init numa_register_meminfo(struct numa_meminfo *mi)
 		unsigned long pfn_align = node_map_pfn_alignment();
 
 		if (pfn_align && pfn_align < PAGES_PER_SECTION) {
-			unsigned long node_align_mb = PFN_PHYS(pfn_align) >> 20;
+			unsigned long node_align_mb = PFN_PHYS(pfn_align) / SZ_1M;
 
-			unsigned long sect_align_mb = PFN_PHYS(PAGES_PER_SECTION) >> 20;
+			unsigned long sect_align_mb = PFN_PHYS(PAGES_PER_SECTION) / SZ_1M;
 
 			pr_warn("Node alignment %luMB < min %luMB, rejecting NUMA config\n",
 				node_align_mb, sect_align_mb);

---
base-commit: c17b750b3ad9f45f2b6f7e6f7f4679844244f0b9
change-id: 20250819-numa-memblks-refac-7b4b5017b598

Best regards,
-- 
Pratyush Brahma <pratyush.brahma@oss.qualcomm.com>

Re: [PATCH v2] mm/numa: Use SZ_1M macro to denote bytes to MB conversion

[Mike Rapoport]

From: Mike Rapoport (Microsoft) <rppt@kernel.org>

On Wed, 20 Aug 2025 06:29:34 +0530, pratyush.brahma@oss.qualcomm.com wrote:
> Replace the manual bitwise conversion of bytes to MB with
> SZ_1M macro, a standard macro used within the mm subsystem,
> to improve readability.
> 
> 

Applied to fixes branch of memblock.git tree, thanks!

I've updated the commit subject:
[1/1] mm: numa,memblock: Use SZ_1M macro to denote bytes to MB conversion
      commit: 4647c4deadcc17f40858be06bcf416369a8f1d57

tree: https://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock
branch: fixes

--
Sincerely yours,
Mike.