• Peter Zijlstra's avatar
    arch/tlb: Clean up simple architectures · 6137fed0
    Peter Zijlstra authored
    For the architectures that do not implement their own tlb_flush() but
    do already use the generic mmu_gather, there are two options:
    
     1) the platform has an efficient flush_tlb_range() and
        asm-generic/tlb.h doesn't need any overrides at all.
    
     2) the platform lacks an efficient flush_tlb_range() and
        we select MMU_GATHER_NO_RANGE to minimize full invalidates.
    
    Convert all 'simple' architectures to one of these two forms.
    
    alpha:	    has no range invalidate -> 2
    arc:	    already used flush_tlb_range() -> 1
    c6x:	    has no range invalidate -> 2
    hexagon:    has an efficient flush_tlb_range() -> 1
                (flush_tlb_mm() is in fact a full range invalidate,
    	     so no need to shoot down everything)
    m68k:	    has inefficient flush_tlb_range() -> 2
    microblaze: has no flush_tlb_range() -> 2
    mips:	    has efficient flush_tlb_range() -> 1
    	    (even though it currently seems to use flush_tlb_mm())
    nds32:	    already uses flush_tlb_range() -> 1
    nios2:	    has inefficient flush_tlb_range() -> 2
    	    (no limit on range iteration)
    openrisc:   has inefficient flush_tlb_range() -> 2
    	    (no limit on range iteration)
    parisc:	    already uses flush_tlb_range() -> 1
    sparc32:    already uses flush_tlb_range() -> 1
    unicore32:  has inefficient flush_tlb_range() -> 2
    	    (no limit on range iteration)
    xtensa:	    has efficient flush_tlb_range() -> 1
    
    Note this also fixes a bug in the existing code for a number
    platforms. Those platforms that did:
    
      tlb_end_vma() -> if (!full_mm) flush_tlb_*()
      tlb_flush -> if (full_mm) flush_tlb_mm()
    
    missed the case of shift_arg_pages(), which doesn't have @fullmm set,
    nor calls into tlb_*vma(), but still frees page-tables and thus needs
    an invalidate. The new code handles this by detecting a non-empty
    range, and either issuing the matching range invalidate or a full
    invalidate, depending on the capabilities.
    
    No change in behavior intended.
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Dave Hansen <dave.hansen@linux.intel.com>
    Cc: David S. Miller <davem@davemloft.net>
    Cc: Greentime Hu <green.hu@gmail.com>
    Cc: Guan Xuetao <gxt@pku.edu.cn>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Helge Deller <deller@gmx.de>
    Cc: Jonas Bonn <jonas@southpole.se>
    Cc: Ley Foon Tan <lftan@altera.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Mark Salter <msalter@redhat.com>
    Cc: Max Filippov <jcmvbkbc@gmail.com>
    Cc: Michal Simek <monstr@monstr.eu>
    Cc: Nick Piggin <npiggin@gmail.com>
    Cc: Paul Burton <paul.burton@mips.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Richard Henderson <rth@twiddle.net>
    Cc: Richard Kuo <rkuo@codeaurora.org>
    Cc: Rik van Riel <riel@surriel.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Vineet Gupta <vgupta@synopsys.com>
    Cc: Will Deacon <will.deacon@arm.com>
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    6137fed0
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