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author | Vineet Gupta <Vineet.Gupta1@synopsys.com> | 2019-11-30 17:51:06 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-12-01 06:29:19 -0800 |
commit | 6aae3425aa9ca776e8201a93494a4a482353d2c3 (patch) | |
tree | 92a2ea5d629f3f56c6fde9d5f04e3c2581166f79 /arch/arc/include | |
parent | ff68dac6d65cd1347dad5d780dd8c90f29dc1b0b (diff) | |
download | linux-stable-6aae3425aa9ca776e8201a93494a4a482353d2c3.tar.gz linux-stable-6aae3425aa9ca776e8201a93494a4a482353d2c3.tar.bz2 linux-stable-6aae3425aa9ca776e8201a93494a4a482353d2c3.zip |
ARC: mm: remove __ARCH_USE_5LEVEL_HACK
Patch series "elide extraneous generated code for folded p4d/pud/pmd", v3.
This series came out of seemingly benign excursion into
understanding/removing __ARCH_USE_5LEVEL_HACK from ARC port showing some
extraneous code being generated despite folded p4d/pud/pmd
| bloat-o-meter2 vmlinux-[AB]*
| add/remove: 0/0 grow/shrink: 3/0 up/down: 130/0 (130)
| function old new delta
| free_pgd_range 548 660 +112
| p4d_clear_bad 2 20 +18
The patches here address that
| bloat-o-meter2 vmlinux-[BF]*
| add/remove: 0/2 grow/shrink: 0/1 up/down: 0/-386 (-386)
| function old new delta
| pud_clear_bad 20 - -20
| p4d_clear_bad 20 - -20
| free_pgd_range 660 314 -346
The code savings are not a whole lot, but still worthwhile IMHO.
This patch (of 5):
With paging code made 5-level compliant, this is no longer needed. ARC
has software page walker with 2 lookup levels (pgd -> pte)
This was expected to be non functional change but ended with slight
code bloat due to needless inclusions of p*d_free_tlb() macros which
will be addressed in further patches.
| bloat-o-meter2 vmlinux-[AB]*
| add/remove: 0/0 grow/shrink: 2/0 up/down: 128/0 (128)
| function old new delta
| free_pgd_range 546 656 +110
| p4d_clear_bad 2 20 +18
| Total: Before=4137148, After=4137276, chg 0.000000%
Link: http://lkml.kernel.org/r/20191016162400.14796-2-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/arc/include')
-rw-r--r-- | arch/arc/include/asm/pgtable.h | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index 7addd0301c51..b917b596f7fb 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -33,7 +33,6 @@ #define _ASM_ARC_PGTABLE_H #include <linux/bits.h> -#define __ARCH_USE_5LEVEL_HACK #include <asm-generic/pgtable-nopmd.h> #include <asm/page.h> #include <asm/mmu.h> /* to propagate CONFIG_ARC_MMU_VER <n> */ |