diff options
author | Andy Lutomirski <luto@kernel.org> | 2017-05-22 15:30:03 -0700 |
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committer | Ingo Molnar <mingo@kernel.org> | 2017-05-24 10:18:27 +0200 |
commit | e73ad5ff2f76da25390e9607cb549691639330c3 (patch) | |
tree | cb59d9a9fba1a6ee7463fa4114184b9f0c4ce8e2 /arch/x86/include | |
parent | b3b90e5af7976e46541f5029a369c9c38c5e4cea (diff) | |
download | linux-e73ad5ff2f76da25390e9607cb549691639330c3.tar.bz2 |
mm, x86/mm: Make the batched unmap TLB flush API more generic
try_to_unmap_flush() used to open-code a rather x86-centric flush
sequence: local_flush_tlb() + flush_tlb_others(). Rearrange the
code so that the arch (only x86 for now) provides
arch_tlbbatch_add_mm() and arch_tlbbatch_flush() and the core code
calls those functions instead.
I'll want this for x86 because, to enable address space ids, I can't
support the flush_tlb_others() mode used by exising
try_to_unmap_flush() implementation with good performance. I can
support the new API fairly easily, though.
I imagine that other architectures may be in a similar position.
Architectures with strong remote flush primitives (arm64?) may have
even worse performance problems with flush_tlb_others() the way that
try_to_unmap_flush() uses it.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/19f25a8581f9fb77876b7ff3b001f89835e34ea3.1495492063.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include')
-rw-r--r-- | arch/x86/include/asm/tlbbatch.h | 16 | ||||
-rw-r--r-- | arch/x86/include/asm/tlbflush.h | 8 |
2 files changed, 24 insertions, 0 deletions
diff --git a/arch/x86/include/asm/tlbbatch.h b/arch/x86/include/asm/tlbbatch.h new file mode 100644 index 000000000000..01a6de16fb96 --- /dev/null +++ b/arch/x86/include/asm/tlbbatch.h @@ -0,0 +1,16 @@ +#ifndef _ARCH_X86_TLBBATCH_H +#define _ARCH_X86_TLBBATCH_H + +#include <linux/cpumask.h> + +#ifdef CONFIG_SMP +struct arch_tlbflush_unmap_batch { + /* + * Each bit set is a CPU that potentially has a TLB entry for one of + * the PFNs being flushed.. + */ + struct cpumask cpumask; +}; +#endif + +#endif /* _ARCH_X86_TLBBATCH_H */ diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index b9db0f8fef55..8f6e2f87511b 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -329,6 +329,14 @@ static inline void reset_lazy_tlbstate(void) this_cpu_write(cpu_tlbstate.active_mm, &init_mm); } +static inline void arch_tlbbatch_add_mm(struct arch_tlbflush_unmap_batch *batch, + struct mm_struct *mm) +{ + cpumask_or(&batch->cpumask, &batch->cpumask, mm_cpumask(mm)); +} + +extern void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch); + #endif /* SMP */ #ifndef CONFIG_PARAVIRT |