From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ross Zwisler Subject: [PATCH 4/6] x86: Use clwb in clflush_cache_range Date: Tue, 11 Nov 2014 11:43:14 -0700 Message-ID: <1415731396-19364-5-git-send-email-ross.zwisler@linux.intel.com> References: <1415731396-19364-1-git-send-email-ross.zwisler@linux.intel.com> Return-path: In-Reply-To: <1415731396-19364-1-git-send-email-ross.zwisler@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org Cc: Ross Zwisler , H Peter Anvin , Ingo Molnar , Thomas Gleixner , David Airlie , dri-devel@lists.freedesktop.org, x86@kernel.org List-Id: dri-devel@lists.freedesktop.org If clwb is available on the system, use it in clflush_cache_range. If clwb is not available, fall back to clflushopt if you can. If clflushopt is not supported, fall all the way back to clflush. Signed-off-by: Ross Zwisler Cc: H Peter Anvin Cc: Ingo Molnar Cc: Thomas Gleixner Cc: David Airlie Cc: dri-devel@lists.freedesktop.org Cc: x86@kernel.org --- arch/x86/mm/pageattr.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 36de293..5229d45 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -126,8 +126,8 @@ within(unsigned long addr, unsigned long start, unsigned long end) * @vaddr: virtual start address * @size: number of bytes to flush * - * clflushopt is an unordered instruction which needs fencing with mfence or - * sfence to avoid ordering issues. + * clflushopt and clwb are unordered instructions which need fencing with + * mfence or sfence to avoid ordering issues. */ void clflush_cache_range(void *vaddr, unsigned int size) { @@ -136,11 +136,11 @@ void clflush_cache_range(void *vaddr, unsigned int size) mb(); for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size) - clflushopt(vaddr); + clwb(vaddr); /* * Flush any possible final partial cacheline: */ - clflushopt(vend); + clwb(vend); mb(); } -- 1.9.3