From f2400abc782dc38a1fee9cfc13589d31f1a0404f Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Sat, 30 Nov 2019 17:51:20 -0800 Subject: asm-generic/mm: stub out p{4,u}d_clear_bad() if __PAGETABLE_P{4,U}D_FOLDED This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat. With this patch we see the following code reduction. | bloat-o-meter2 vmlinux-D-elide-p4d_free_tlb vmlinux-E-elide-p?d_clear_bad | add/remove: 0/2 grow/shrink: 0/0 up/down: 0/-40 (-40) | function old new delta | pud_clear_bad 20 - -20 | p4d_clear_bad 20 - -20 | Total: Before=4136930, After=4136890, chg -1.000000% Link: http://lkml.kernel.org/r/20191016162400.14796-6-vgupta@synopsys.com Signed-off-by: Vineet Gupta Acked-by: Kirill A. Shutemov Cc: Arnd Bergmann Cc: Will Deacon Cc: "Aneesh Kumar K . V" Cc: Nick Piggin Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 11 +++++++++++ mm/pgtable-generic.c | 9 +++++++++ 2 files changed, 20 insertions(+) diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 818691846c90..9cdcbc7c0b7b 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -558,8 +558,19 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) * Do the tests inline, but report and clear the bad entry in mm/memory.c. */ void pgd_clear_bad(pgd_t *); + +#ifndef __PAGETABLE_P4D_FOLDED void p4d_clear_bad(p4d_t *); +#else +#define p4d_clear_bad(p4d) do { } while (0) +#endif + +#ifndef __PAGETABLE_PUD_FOLDED void pud_clear_bad(pud_t *); +#else +#define pud_clear_bad(p4d) do { } while (0) +#endif + void pmd_clear_bad(pmd_t *); static inline int pgd_none_or_clear_bad(pgd_t *pgd) diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 532c29276fce..3d7c01e76efc 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -24,18 +24,27 @@ void pgd_clear_bad(pgd_t *pgd) pgd_clear(pgd); } +#ifndef __PAGETABLE_P4D_FOLDED void p4d_clear_bad(p4d_t *p4d) { p4d_ERROR(*p4d); p4d_clear(p4d); } +#endif +#ifndef __PAGETABLE_PUD_FOLDED void pud_clear_bad(pud_t *pud) { pud_ERROR(*pud); pud_clear(pud); } +#endif +/* + * Note that the pmd variant below can't be stub'ed out just as for p4d/pud + * above. pmd folding is special and typically pmd_* macros refer to upper + * level even when folded + */ void pmd_clear_bad(pmd_t *pmd) { pmd_ERROR(*pmd); -- cgit