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author | Yinghai Lu <yhlu.kernel@gmail.com> | 2008-10-05 01:50:32 +0400 |
---|---|---|
committer | H. Peter Anvin <hpa@zytor.com> | 2008-10-05 07:09:14 +0400 |
commit | 99e1aa17ce434010dd820b583628370cc15f10f3 (patch) | |
tree | f856dd2dd02d6986f590eb47b2fe3cf814807b57 | |
parent | 42fde7a05c5d6dc76e518ae12091ea897b1c132b (diff) | |
download | linux-99e1aa17ce434010dd820b583628370cc15f10f3.tar.xz |
x86: mtrr_cleanup: first 1M may be covered in var mtrrs
The first 1M is don't care when it comes to the variables MTRRs.
Cover it as WB as a heuristic approximation; this is generally what we
want to minimize the number of registers.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
-rw-r--r-- | arch/x86/kernel/cpu/mtrr/main.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 9086b38fbabe..663e530e08e0 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -1293,6 +1293,15 @@ static int __init mtrr_cleanup(unsigned address_bits) } nr_range = x86_get_mtrr_mem_range(range, 0, extra_remove_base, extra_remove_size); + /* + * [0, 1M) should always be coverred by var mtrr with WB + * and fixed mtrrs should take effective before var mtrr for it + */ + nr_range = add_range_with_merge(range, nr_range, 0, + (1ULL<<(20 - PAGE_SHIFT)) - 1); + /* sort the ranges */ + sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL); + range_sums = sum_ranges(range, nr_range); printk(KERN_INFO "total RAM coverred: %ldM\n", range_sums >> (20 - PAGE_SHIFT)); |