From owner-svn-src-all@freebsd.org Fri Feb 5 05:31:32 2016 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id E085CA9BB80; Fri, 5 Feb 2016 05:31:32 +0000 (UTC) (envelope-from sephe@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 97114CF7; Fri, 5 Feb 2016 05:31:32 +0000 (UTC) (envelope-from sephe@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u155VVj6072683; Fri, 5 Feb 2016 05:31:31 GMT (envelope-from sephe@FreeBSD.org) Received: (from sephe@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u155VVH0072682; Fri, 5 Feb 2016 05:31:31 GMT (envelope-from sephe@FreeBSD.org) Message-Id: <201602050531.u155VVH0072682@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: sephe set sender to sephe@FreeBSD.org using -f From: Sepherosa Ziehau Date: Fri, 5 Feb 2016 05:31:31 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r295303 - head/sys/dev/hyperv/netvsc X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Feb 2016 05:31:33 -0000 Author: sephe Date: Fri Feb 5 05:31:31 2016 New Revision: 295303 URL: https://svnweb.freebsd.org/changeset/base/295303 Log: hyperv/hn: Recover half of the chimney sending space We lost half of the chimney sending space, because we mis-used ffs() on a 64 bits mask, where ffsl() should be used. While I'm here: - Use system atomic operation instead. - Stringent chimney sending index assertion. Reviewed by: adrian Approved by: adrian (mentor) MFC after: 1 week Sponsored by: Microsoft OSTC Differential Revision: https://reviews.freebsd.org/D5159 Modified: head/sys/dev/hyperv/netvsc/hv_net_vsc.c Modified: head/sys/dev/hyperv/netvsc/hv_net_vsc.c ============================================================================== --- head/sys/dev/hyperv/netvsc/hv_net_vsc.c Fri Feb 5 05:25:11 2016 (r295302) +++ head/sys/dev/hyperv/netvsc/hv_net_vsc.c Fri Feb 5 05:31:31 2016 (r295303) @@ -136,15 +136,15 @@ hv_nv_get_next_send_section(netvsc_dev * int i; for (i = 0; i < bitsmap_words; i++) { - idx = ffs(~bitsmap[i]); + idx = ffsl(~bitsmap[i]); if (0 == idx) continue; idx--; - if (i * BITS_PER_LONG + idx >= net_dev->send_section_count) - return (ret); + KASSERT(i * BITS_PER_LONG + idx < net_dev->send_section_count, + ("invalid i %d and idx %lu", i, idx)); - if (synch_test_and_set_bit(idx, &bitsmap[i])) + if (atomic_testandset_long(&bitsmap[i], idx)) continue; ret = i * BITS_PER_LONG + idx; @@ -789,8 +789,27 @@ hv_nv_on_send_completion(netvsc_dev *net if (NULL != net_vsc_pkt) { if (net_vsc_pkt->send_buf_section_idx != NVSP_1_CHIMNEY_SEND_INVALID_SECTION_INDEX) { - synch_change_bit(net_vsc_pkt->send_buf_section_idx, - net_dev->send_section_bitsmap); + u_long mask; + int idx; + + idx = net_vsc_pkt->send_buf_section_idx / + BITS_PER_LONG; + KASSERT(idx < net_dev->bitsmap_words, + ("invalid section index %u", + net_vsc_pkt->send_buf_section_idx)); + mask = 1UL << + (net_vsc_pkt->send_buf_section_idx % + BITS_PER_LONG); + + KASSERT(net_dev->send_section_bitsmap[idx] & + mask, + ("index bitmap 0x%lx, section index %u, " + "bitmap idx %d, bitmask 0x%lx", + net_dev->send_section_bitsmap[idx], + net_vsc_pkt->send_buf_section_idx, + idx, mask)); + atomic_clear_long( + &net_dev->send_section_bitsmap[idx], mask); } /* Notify the layer above us */