From patchwork Wed Mar 28 00:48:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Long Li X-Patchwork-Id: 10311951 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1A9966037D for ; Wed, 28 Mar 2018 00:50:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 10DA929E67 for ; Wed, 28 Mar 2018 00:50:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0586A29E6C; Wed, 28 Mar 2018 00:50:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B58C029E72 for ; Wed, 28 Mar 2018 00:50:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752744AbeC1AuC (ORCPT ); Tue, 27 Mar 2018 20:50:02 -0400 Received: from a2nlsmtp01-03.prod.iad2.secureserver.net ([198.71.225.37]:53112 "EHLO a2nlsmtp01-03.prod.iad2.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752008AbeC1At6 (ORCPT ); Tue, 27 Mar 2018 20:49:58 -0400 Received: from linuxonhyperv2.linuxonhyperv.com ([107.180.71.197]) by : HOSTING RELAY : with SMTP id 0zGqf11TaTrNg0zGqfYeNk; Tue, 27 Mar 2018 17:48:56 -0700 x-originating-ip: 107.180.71.197 Received: from longli by linuxonhyperv2.linuxonhyperv.com with local (Exim 4.89_1) (envelope-from ) id 1f0zGq-0005wF-M8; Tue, 27 Mar 2018 17:48:56 -0700 From: Long Li To: "K . Y . Srinivasan" , Haiyang Zhang , Stephen Hemminger , "James E . J . Bottomley" , "Martin K . Petersen" , devel@linuxdriverproject.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Long Li Subject: [Resend Patch 1/3] Vmbus: Add function to report available ring buffer to write in total ring size percentage Date: Tue, 27 Mar 2018 17:48:38 -0700 Message-Id: <20180328004840.22787-1-longli@linuxonhyperv.com> X-Mailer: git-send-email 2.15.1 Reply-To: longli@microsoft.com X-CMAE-Envelope: MS4wfNJ6pGtR6gGAFdPhrWcC9kiZ9fcY+GIdI4EPrRfQwpWOSV6mwKrIzdEA1/pU9cZrm5I3e/VbeROWV/AX4TdVkymFXUoVRpBc/yteVC8Bu/u9GKjRN9lT +0VCyMBM1NY3BlN1/oRsTF2cLcCEYIojwXzdP7cDY/BT/XpDkmwz3L//7gAyOvcc/4moHPY3fZgPtPDqMYxmbgE341inpye7Pe9CfLWauDnrR7Qj/v4bA9vs Md3SvZh6owgEYGdVLiI7i6p7CprmjSO79t2vBHIHYM77rMpGLJJGHB34u+V0SrGcgRTHhoBarG0wstORu7BJb4DSLJoO4SWbBoqNUlhH6q6pwW1m8U1I6XGQ a84a4MlWL8dfN0zgaDT9VxBsM2IWiaikbduErwhT0++EyLL3a21yIeTwsEwm+PULbAB/ybMoakb7SPkRLC9VuKIXEjyEk48PSPLmm7EJLuYz3zTpGQ2D9vy+ 8M4459AccNe0D6moXR2HPXLYWhcmTnxRetFLjru6fBiuQOOVFDUlu8A2WbtWpABm9omA08OF6wU4i4GG Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Long Li Netvsc has a function to calculate how much ring buffer in percentage is available to write. This function is also useful for storvsc and other vmbus devices. Define a similar function in vmbus to be used by other vmbus devices. Signed-off-by: Long Li --- drivers/hv/ring_buffer.c | 2 ++ include/linux/hyperv.h | 12 ++++++++++++ 2 files changed, 14 insertions(+) diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 8699bb969e7e..3c836c099a8f 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -227,6 +227,8 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, ring_info->ring_buffer->feature_bits.value = 1; ring_info->ring_size = page_cnt << PAGE_SHIFT; + ring_info->ring_size_div10_reciprocal = + reciprocal_value(ring_info->ring_size / 10); ring_info->ring_datasize = ring_info->ring_size - sizeof(struct hv_ring_buffer); diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 2048f3c3b68a..eb7204851089 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -36,6 +36,7 @@ #include #include #include +#include #define MAX_PAGE_BUFFER_COUNT 32 #define MAX_MULTIPAGE_BUFFER_COUNT 32 /* 128K */ @@ -121,6 +122,7 @@ struct hv_ring_buffer { struct hv_ring_buffer_info { struct hv_ring_buffer *ring_buffer; u32 ring_size; /* Include the shared header */ + struct reciprocal_value ring_size_div10_reciprocal; spinlock_t ring_lock; u32 ring_datasize; /* < ring_size */ @@ -155,6 +157,16 @@ static inline u32 hv_get_bytes_to_write(const struct hv_ring_buffer_info *rbi) return write; } +static inline u32 hv_get_avail_to_write_percent( + const struct hv_ring_buffer_info *rbi) +{ + u32 avail_write = hv_get_bytes_to_write(rbi); + + return reciprocal_divide( + (avail_write << 3) + (avail_write << 1), + rbi->ring_size_div10_reciprocal); +} + /* * VMBUS version is 32 bit entity broken up into * two 16 bit quantities: major_number. minor_number.