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| author | Uladzislau Rezki (Sony) <urezki@gmail.com> | 2021-11-05 13:39:34 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-11-06 13:30:37 -0700 |
| commit | 066fed59d8a1bab4f3213e8fe413c54e4a76b77a (patch) | |
| tree | 17eefc3480df5183ccbb1a5c2ae974542c706167 | |
| parent | 9f531973dff39c671219352573ad5df6d0d9a58c (diff) | |
| download | lwn-066fed59d8a1bab4f3213e8fe413c54e4a76b77a.tar.gz lwn-066fed59d8a1bab4f3213e8fe413c54e4a76b77a.zip | |
mm/vmalloc: check various alignments when debugging
Before we did not guarantee a free block with lowest start address for
allocations with alignment >= PAGE_SIZE. Because an alignment overhead
was included into a search length like below:
length = size + align - 1;
doing so we make sure that a bigger block would fit after applying an
alignment adjustment. Now there is no such limitation, i.e. any
alignment that user wants to apply will result to a lowest address of
returned free area.
Link: https://lkml.kernel.org/r/20211004142829.22222-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Ping Fang <pifang@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/vmalloc.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 0d835bd7fb5f..d4770396799a 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1269,7 +1269,7 @@ find_vmap_lowest_linear_match(unsigned long size, } static void -find_vmap_lowest_match_check(unsigned long size) +find_vmap_lowest_match_check(unsigned long size, unsigned long align) { struct vmap_area *va_1, *va_2; unsigned long vstart; @@ -1278,8 +1278,8 @@ find_vmap_lowest_match_check(unsigned long size) get_random_bytes(&rnd, sizeof(rnd)); vstart = VMALLOC_START + rnd; - va_1 = find_vmap_lowest_match(size, 1, vstart); - va_2 = find_vmap_lowest_linear_match(size, 1, vstart); + va_1 = find_vmap_lowest_match(size, align, vstart); + va_2 = find_vmap_lowest_linear_match(size, align, vstart); if (va_1 != va_2) pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n", @@ -1458,7 +1458,7 @@ __alloc_vmap_area(unsigned long size, unsigned long align, return vend; #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK - find_vmap_lowest_match_check(size); + find_vmap_lowest_match_check(size, align); #endif return nva_start_addr; |