From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:44418 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753030AbdJSNj3 (ORCPT ); Thu, 19 Oct 2017 09:39:29 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stephen Hemminger , "K. Y. Srinivasan" Subject: [PATCH 4.13 10/11] vmbus: eliminate duplicate cached index Date: Thu, 19 Oct 2017 15:39:05 +0200 Message-Id: <20171019131700.825231545@linuxfoundation.org> In-Reply-To: <20171019131659.388456140@linuxfoundation.org> References: <20171019131659.388456140@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephen Hemminger commit 05d00bc94ac27d220d8a78e365d7fa3a26dcca17 upstream. Don't need cached read index anymore now that packet iterator is used. The iterator has the original read index until the visible read_index is updated. Signed-off-by: Stephen Hemminger Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/hv/ring_buffer.c | 17 ++++------------- include/linux/hyperv.h | 14 -------------- 2 files changed, 4 insertions(+), 27 deletions(-) --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -358,9 +358,6 @@ struct vmpacket_descriptor *hv_pkt_iter_ { struct hv_ring_buffer_info *rbi = &channel->inbound; - /* set state for later hv_pkt_iter_close */ - rbi->cached_read_index = rbi->ring_buffer->read_index; - if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor)) return NULL; @@ -388,10 +385,7 @@ __hv_pkt_iter_next(struct vmbus_channel rbi->priv_read_index -= dsize; /* more data? */ - if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor)) - return NULL; - else - return hv_get_ring_buffer(rbi) + rbi->priv_read_index; + return hv_pkt_iter_first(channel); } EXPORT_SYMBOL_GPL(__hv_pkt_iter_next); @@ -401,7 +395,7 @@ EXPORT_SYMBOL_GPL(__hv_pkt_iter_next); void hv_pkt_iter_close(struct vmbus_channel *channel) { struct hv_ring_buffer_info *rbi = &channel->inbound; - u32 cur_write_sz, cached_write_sz; + u32 orig_write_sz = hv_get_bytes_to_write(rbi); u32 pending_sz; /* @@ -430,13 +424,10 @@ void hv_pkt_iter_close(struct vmbus_chan if (pending_sz == 0) return; - cur_write_sz = hv_get_bytes_to_write(rbi); - - if (cur_write_sz < pending_sz) + if (hv_get_bytes_to_write(rbi) < pending_sz) return; - cached_write_sz = hv_get_cached_bytes_to_write(rbi); - if (cached_write_sz < pending_sz) + if (orig_write_sz < pending_sz) vmbus_setevent(channel); } EXPORT_SYMBOL_GPL(hv_pkt_iter_close); --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -127,7 +127,6 @@ struct hv_ring_buffer_info { u32 ring_data_startoffset; u32 priv_write_index; u32 priv_read_index; - u32 cached_read_index; }; /* @@ -180,19 +179,6 @@ static inline u32 hv_get_bytes_to_write( return write; } -static inline u32 hv_get_cached_bytes_to_write( - const struct hv_ring_buffer_info *rbi) -{ - u32 read_loc, write_loc, dsize, write; - - dsize = rbi->ring_datasize; - read_loc = rbi->cached_read_index; - write_loc = rbi->ring_buffer->write_index; - - write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : - read_loc - write_loc; - return write; -} /* * VMBUS version is 32 bit entity broken up into * two 16 bit quantities: major_number. minor_number.