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Subject[PATCH 37/46] x86, mm: use pfn instead of pos in split_mem_range
Date
could save some bit shifting operations.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
arch/x86/mm/init.c | 29 ++++++++++++++---------------
1 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index a4fdf31..e430f1e 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -200,12 +200,11 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
unsigned long end)
{
unsigned long start_pfn, end_pfn;
- unsigned long pos;
+ unsigned long pfn;
int i;

/* head if not big page alignment ? */
- start_pfn = PFN_DOWN(start);
- pos = PFN_PHYS(start_pfn);
+ pfn = start_pfn = PFN_DOWN(start);
#ifdef CONFIG_X86_32
/*
* Don't use a large page for the first 2/4MB of memory
@@ -213,26 +212,26 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
* and overlapping MTRRs into large pages can cause
* slowdowns.
*/
- if (pos == 0)
+ if (pfn == 0)
end_pfn = PFN_DOWN(PMD_SIZE);
else
- end_pfn = PFN_DOWN(round_up(pos, PMD_SIZE));
+ end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
#else /* CONFIG_X86_64 */
- end_pfn = PFN_DOWN(round_up(pos, PMD_SIZE));
+ end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
#endif
if (end_pfn > PFN_DOWN(end))
end_pfn = PFN_DOWN(end);
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
- pos = PFN_PHYS(end_pfn);
+ pfn = end_pfn;
}

/* big page (2M) range */
- start_pfn = PFN_DOWN(round_up(pos, PMD_SIZE));
+ start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
#ifdef CONFIG_X86_32
end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
#else /* CONFIG_X86_64 */
- end_pfn = PFN_DOWN(round_up(pos, PUD_SIZE));
+ end_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
if (end_pfn > PFN_DOWN(round_down(end, PMD_SIZE)))
end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
#endif
@@ -240,32 +239,32 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask & (1<<PG_LEVEL_2M));
- pos = PFN_PHYS(end_pfn);
+ pfn = end_pfn;
}

#ifdef CONFIG_X86_64
/* big page (1G) range */
- start_pfn = PFN_DOWN(round_up(pos, PUD_SIZE));
+ start_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
end_pfn = PFN_DOWN(round_down(end, PUD_SIZE));
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask &
((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
- pos = PFN_PHYS(end_pfn);
+ pfn = end_pfn;
}

/* tail is not big page (1G) alignment */
- start_pfn = PFN_DOWN(round_up(pos, PMD_SIZE));
+ start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask & (1<<PG_LEVEL_2M));
- pos = PFN_PHYS(end_pfn);
+ pfn = end_pfn;
}
#endif

/* tail is not big page (2M) alignment */
- start_pfn = PFN_DOWN(pos);
+ start_pfn = pfn;
end_pfn = PFN_DOWN(end);
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);

--
1.7.7


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