Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758685AbaKUPHP (ORCPT ); Fri, 21 Nov 2014 10:07:15 -0500 Received: from mail-ig0-f181.google.com ([209.85.213.181]:42286 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758510AbaKUPHI (ORCPT ); Fri, 21 Nov 2014 10:07:08 -0500 From: Pranith Kumar To: "K. Y. Srinivasan" , Haiyang Zhang , devel@linuxdriverproject.org (open list:Hyper-V CORE AND...), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 4/9] hyperv: Replace smp_read_barrier_depends() with lockless_dereference() Date: Fri, 21 Nov 2014 10:05:58 -0500 Message-Id: <1416582363-20661-5-git-send-email-bobby.prani@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> References: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Recently lockless_dereference() was added which can be used in place of hard-coding smp_read_barrier_depends(). The following PATCH makes the change. Signed-off-by: Pranith Kumar --- include/linux/hyperv.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 08cfaff..06418b1 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -127,13 +127,12 @@ hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi, u32 *read, u32 *write) { u32 read_loc, write_loc, dsize; - - smp_read_barrier_depends(); + struct hv_ring_buffer_info *rbi_p = lockless_dereference(rbi); /* Capture the read/write indices before they changed */ - read_loc = rbi->ring_buffer->read_index; - write_loc = rbi->ring_buffer->write_index; - dsize = rbi->ring_datasize; + read_loc = rbi_p->ring_buffer->read_index; + write_loc = rbi_p->ring_buffer->write_index; + dsize = rbi_p->ring_datasize; *write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : read_loc - write_loc; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/