[PATCH RESEND 2/3] x86, mm: Update min_pfn_mapped in add_pfn_range_mapped().

From: Tang Chen
Date: Mon Sep 02 2013 - 06:32:18 EST


In current kernel, we update min_pfn_mapped and max_pfn_mapped like this:

init_mem_mapping()
{
while ( a loop iterates all memory ranges ) {
init_range_memory_mapping();
|->init_memory_mapping()
|->kernel_physical_mapping_init()
|->add_pfn_range_mapped()
|-> update max_pfn_mapped;

update min_pfn_mapped;
}
}

max_pfn_mapped is updated in add_pfn_range_mapped() when a range of memory
is mapped. But min_pfn_mapped is updated in init_mem_mapping(). We can also
update min_pfn_mapped in add_pfn_range_mapped().

Signed-off-by: Tang Chen <tangchen@xxxxxxxxxxxxxx>
---
arch/x86/mm/init.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 5b2eaca..a97749f 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -313,6 +313,7 @@ static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn)
nr_pfn_mapped = clean_sort_range(pfn_mapped, E820_X_MAX);

max_pfn_mapped = max(max_pfn_mapped, end_pfn);
+ min_pfn_mapped = min(min_pfn_mapped, start_pfn);
}

bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn)
@@ -442,7 +443,6 @@ void __init init_mem_mapping(void)
new_mapped_ram_size = init_range_memory_mapping(start,
last_start);
last_start = start;
- min_pfn_mapped = last_start >> PAGE_SHIFT;
/* only increase step_size after big range get mapped */
if (new_mapped_ram_size > mapped_ram_size)
step_size <<= STEP_SIZE_SHIFT;
--
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/