On 11.07.23 06:48, Aneesh Kumar K.V wrote:
Some architectures would want different restrictions. Hence add an
architecture-specific override.
Both the PMD_SIZE check and pageblock alignment check are moved there.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 1b19462f4e72..07c99b0cc371 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1247,12 +1247,20 @@ static int online_memory_block(struct memory_block *mem, void *arg)
return device_online(&mem->dev);
}
-static bool mhp_supports_memmap_on_memory(unsigned long size)
+#ifndef arch_supports_memmap_on_memory
Can we make that a __weak function instead?
+static inline bool arch_supports_memmap_on_memory(unsigned long size)
{
- unsigned long nr_vmemmap_pages = size / PAGE_SIZE;
+ unsigned long nr_vmemmap_pages = size >> PAGE_SHIFT;
unsigned long vmemmap_size = nr_vmemmap_pages * sizeof(struct page);
unsigned long remaining_size = size - vmemmap_size;
+ return IS_ALIGNED(vmemmap_size, PMD_SIZE) &&
+ IS_ALIGNED(remaining_size, (pageblock_nr_pages << PAGE_SHIFT));
You're moving that check back to mhp_supports_memmap_on_memory() in the
following patch, where it actually belongs. So this check should stay in
mhp_supports_memmap_on_memory(). Might be reasonable to factor out the
vmemmap_size calculation.
Also, let's a comment
/*
* As default, we want the vmemmap to span a complete PMD such that we
* can map the vmemmap using a single PMD if supported by the
* architecture.
*/
return IS_ALIGNED(vmemmap_size, PMD_SIZE);
+}
+#endif
+
+static bool mhp_supports_memmap_on_memory(unsigned long size)
+{
/*
* Besides having arch support and the feature enabled at runtime, we
* need a few more assumptions to hold true:
@@ -1280,9 +1288,8 @@ static bool mhp_supports_memmap_on_memory(unsigned long size)
* populate a single PMD.
*/
return mhp_memmap_on_memory() &&
- size == memory_block_size_bytes() &&
- IS_ALIGNED(vmemmap_size, PMD_SIZE) &&
- IS_ALIGNED(remaining_size, (pageblock_nr_pages << PAGE_SHIFT));
+ size == memory_block_size_bytes() &&
If you keep the properly aligned indentation, this will not be detected
as a change by git.
+ arch_supports_memmap_on_memory(size);
}
/*
--
Cheers,
David / dhildenb
