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From: Mark Salter <msalter@redhat.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Mark Salter <msalter@redhat.com>
Subject: [PATCH 0/2] arm64: TLB flush issues
Date: Fri,  2 May 2014 11:20:33 -0400	[thread overview]
Message-ID: <1399044035-11274-1-git-send-email-msalter@redhat.com> (raw)

As explained in more detail in the second patch, I have observed a soft
lockup under some loads. These lockups were in flush_tlb_kernel_range()
which was looping through a very large address range. While looking into
this, I also noticed the flush routines in tlb.S were not properly
handling pages larger than 4k. This is corrected in the first patch.
The second patch limits the loop size for the flush_tlb_[kernel_]range
functions. It uses an arbitrary constant to limit the loop, but it
would be better if it were based on actual tlb size or some other
heuristic.

Mark Salter (2):
  arm64: fix unnecessary tlb flushes
  arm64: fix soft lockup due to large tlb flush range

 arch/arm64/include/asm/tlbflush.h | 28 +++++++++++++++++++++++++---
 arch/arm64/mm/tlb.S               |  4 ++--
 2 files changed, 27 insertions(+), 5 deletions(-)

-- 
1.9.0


             reply	other threads:[~2014-05-02 15:21 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-02 15:20 Mark Salter [this message]
2014-05-02 15:20 ` [PATCH 1/2] arm64: fix unnecessary tlb flushes Mark Salter
2014-05-02 15:20 ` [PATCH 2/2] arm64: fix soft lockup due to large tlb flush range Mark Salter
2014-05-02 15:30 ` [PATCH 0/2] arm64: TLB flush issues Steve Capper
2014-05-02 15:50   ` Mark Salter

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