From 5bf65b9ba67226eae9ffc398a0369fc4da35c259 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Tue, 24 Nov 2009 02:46:59 -0800 Subject: [PATCH] x86, mtrr: Fix sorting of mtrr after subtracting In some cases we can coalesce MTRR entries after cleanup; this may allow us to have more entries. As such, introduce clean_sort_range to to sort and coaelsce the MTRR entries. Signed-off-by: Yinghai Lu LKML-Reference: <4B0BB9A3.5020908@kernel.org> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/mtrr/cleanup.c | 49 ++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c index 6e49f6f91f3..6987af786c0 100644 --- a/arch/x86/kernel/cpu/mtrr/cleanup.c +++ b/arch/x86/kernel/cpu/mtrr/cleanup.c @@ -170,6 +170,41 @@ static int __init cmp_range(const void *x1, const void *x2) return start1 - start2; } +static int __init clean_sort_range(struct res_range *range, int az) +{ + int i, j, k = az - 1, nr_range = 0; + + for (i = 0; i < k; i++) { + if (range[i].end) + continue; + for (j = k; j > i; j--) { + if (range[j].end) { + k = j; + break; + } + } + if (j == i) + break; + range[i].start = range[k].start; + range[i].end = range[k].end; + range[k].start = 0; + range[k].end = 0; + k--; + } + /* count it */ + for (i = 0; i < az; i++) { + if (!range[i].end) { + nr_range = i; + break; + } + } + + /* sort them */ + sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL); + + return nr_range; +} + #define BIOS_BUG_MSG KERN_WARNING \ "WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n" @@ -223,22 +258,18 @@ x86_get_mtrr_mem_range(struct res_range *range, int nr_range, subtract_range(range, extra_remove_base, extra_remove_base + extra_remove_size - 1); - /* get new range num */ - nr_range = 0; - for (i = 0; i < RANGE_NUM; i++) { - if (!range[i].end) - continue; - nr_range++; - } if (debug_print) { printk(KERN_DEBUG "After UC checking\n"); - for (i = 0; i < nr_range; i++) + for (i = 0; i < RANGE_NUM; i++) { + if (!range[i].end) + continue; printk(KERN_DEBUG "MTRR MAP PFN: %016lx - %016lx\n", range[i].start, range[i].end + 1); + } } /* sort the ranges */ - sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL); + nr_range = clean_sort_range(range, RANGE_NUM); if (debug_print) { printk(KERN_DEBUG "After sorting\n"); for (i = 0; i < nr_range; i++) -- 2.39.3