[PATCH 10/13] memblock, x86: Reimplement memblock_find_dma_reserve() using iterators
From: Tejun Heo <tj@kernel.org>
Date: 2011-07-12 09:17:34
Also in:
lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra
memblock_find_dma_reserve() wants to find out how much memory is reserved under MAX_DMA_PFN. memblock_x86_memory_[free_]in_range() are used to find out the amounts of all available and free memory in the area, which are then subtracted to find out the amount of reservation. memblock_x86_memblock_[free_]in_range() are implemented using __memblock_x86_memory_in_range() which builds ranges from memblock and then count them, which is rather unnecessarily complex. This patch open codes the counting logic directly in memblock_find_dma_reserve() using memblock iterators and removes now unused __memblock_x86_memory_in_range() and find_range_array(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <redacted> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> --- arch/x86/include/asm/memblock.h | 2 - arch/x86/kernel/e820.c | 25 +++++++++-- arch/x86/mm/memblock.c | 87 --------------------------------------- 3 files changed, 20 insertions(+), 94 deletions(-)
diff --git a/arch/x86/include/asm/memblock.h b/arch/x86/include/asm/memblock.h
index bc9e44b..a0cc7d6 100644
--- a/arch/x86/include/asm/memblock.h
+++ b/arch/x86/include/asm/memblock.h@@ -7,7 +7,5 @@ void memblock_x86_reserve_range(u64 start, u64 end, char *name); void memblock_x86_free_range(u64 start, u64 end); u64 memblock_x86_hole_size(u64 start, u64 end); -u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit); -u64 memblock_x86_memory_in_range(u64 addr, u64 limit); #endif
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index b99d940..84475f1 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c@@ -1093,15 +1093,30 @@ void __init memblock_x86_fill(void) void __init memblock_find_dma_reserve(void) { #ifdef CONFIG_X86_64 - u64 free_size_pfn; - u64 mem_size_pfn; + u64 nr_pages = 0, nr_free_pages = 0; + unsigned long start_pfn, end_pfn; + phys_addr_t start, end; + int i; + u64 u; + /* * need to find out used area below MAX_DMA_PFN * need to use memblock to get free size in [0, MAX_DMA_PFN] * at first, and assume boot_mem will not take below MAX_DMA_PFN */ - mem_size_pfn = memblock_x86_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT; - free_size_pfn = memblock_x86_free_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT; - set_dma_reserve(mem_size_pfn - free_size_pfn); + for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) { + start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN); + end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN); + nr_pages += end_pfn - start_pfn; + } + + for_each_free_mem_range(u, MAX_NUMNODES, &start, &end, NULL) { + start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN); + end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN); + if (start_pfn < end_pfn) + nr_free_pages += end_pfn - start_pfn; + } + + set_dma_reserve(nr_pages - nr_free_pages); #endif }
diff --git a/arch/x86/mm/memblock.c b/arch/x86/mm/memblock.c
index 4107c1a..a9d0972 100644
--- a/arch/x86/mm/memblock.c
+++ b/arch/x86/mm/memblock.c@@ -7,93 +7,6 @@ #include <linux/mm.h> #include <linux/range.h> -static __init struct range *find_range_array(int count) -{ - u64 end, size, mem; - struct range *range; - - size = sizeof(struct range) * count; - end = memblock.current_limit; - - mem = memblock_find_in_range(0, end, size, sizeof(struct range)); - if (!mem) - panic("can not find more space for range array"); - - /* - * This range is tempoaray, so don't reserve it, it will not be - * overlapped because We will not alloccate new buffer before - * We discard this one - */ - range = __va(mem); - memset(range, 0, size); - - return range; -} - -static u64 __init __memblock_x86_memory_in_range(u64 addr, u64 limit, bool get_free) -{ - int i, count; - struct range *range; - int nr_range; - u64 final_start, final_end; - u64 free_size; - struct memblock_region *r; - - count = (memblock.reserved.cnt + memblock.memory.cnt) * 2; - - range = find_range_array(count); - nr_range = 0; - - addr = PFN_UP(addr); - limit = PFN_DOWN(limit); - - for_each_memblock(memory, r) { - final_start = PFN_UP(r->base); - final_end = PFN_DOWN(r->base + r->size); - if (final_start >= final_end) - continue; - if (final_start >= limit || final_end <= addr) - continue; - - nr_range = add_range(range, count, nr_range, final_start, final_end); - } - subtract_range(range, count, 0, addr); - subtract_range(range, count, limit, -1ULL); - - /* Subtract memblock.reserved.region in range ? */ - if (!get_free) - goto sort_and_count_them; - for_each_memblock(reserved, r) { - final_start = PFN_DOWN(r->base); - final_end = PFN_UP(r->base + r->size); - if (final_start >= final_end) - continue; - if (final_start >= limit || final_end <= addr) - continue; - - subtract_range(range, count, final_start, final_end); - } - -sort_and_count_them: - nr_range = clean_sort_range(range, count); - - free_size = 0; - for (i = 0; i < nr_range; i++) - free_size += range[i].end - range[i].start; - - return free_size << PAGE_SHIFT; -} - -u64 __init memblock_x86_free_memory_in_range(u64 addr, u64 limit) -{ - return __memblock_x86_memory_in_range(addr, limit, true); -} - -u64 __init memblock_x86_memory_in_range(u64 addr, u64 limit) -{ - return __memblock_x86_memory_in_range(addr, limit, false); -} - void __init memblock_x86_reserve_range(u64 start, u64 end, char *name) { if (start == end)
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1.7.6