From patchwork Sun Mar 6 01:57:25 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Yang X-Patchwork-Id: 8512131 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 578E99F314 for ; Sun, 6 Mar 2016 02:01:56 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 967282010C for ; Sun, 6 Mar 2016 02:01:55 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DE888200F4 for ; Sun, 6 Mar 2016 02:01:54 +0000 (UTC) Received: from localhost ([::1]:48828 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1acO14-0004vq-0V for patchwork-qemu-devel@patchwork.kernel.org; Sat, 05 Mar 2016 21:01:54 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53815) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1acO0w-0004vX-8O for qemu-devel@nongnu.org; Sat, 05 Mar 2016 21:01:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1acO0t-00051K-1L for qemu-devel@nongnu.org; Sat, 05 Mar 2016 21:01:46 -0500 Received: from mail-pf0-x22a.google.com ([2607:f8b0:400e:c00::22a]:36449) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1acO0s-00051G-PY for qemu-devel@nongnu.org; Sat, 05 Mar 2016 21:01:42 -0500 Received: by mail-pf0-x22a.google.com with SMTP id 63so57994079pfe.3 for ; Sat, 05 Mar 2016 18:01:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=ZY/M2zK9SxghpRix15w+QfMP2DR+O1wg/KSGOrIhRAs=; b=X6idyoI0oAdT2lxAIB9rJCsg6Z5rYb/6VJwZQEp9gJRYjfV7fs0P3mUFFsVOVYrWyW 8bnIuMopuwc1JqxkkDQnNwQtr/AbYiQYPGRfvHx3VtbZb3O3GNUBMo5WSkl1jDTB7lIC sfb/G+LBPb3cy71sKbAFnOwC0G7t+fmoEksv60TmfXyRxFuYcC9rvb8DQLRV0jWIIGfg FKgJnuJAFdRkU3dsDa55jO8A1HDA1zoA6Tc7/XYUoEa2z3vTauxAisVXd2lEysmdqCX+ vK7hFsgtikLRR0shtACT5oIVfeAn1TDdwgOvEFUUyQdFH3nQgxK19EISQKDlihe4AU9Q N0Iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=ZY/M2zK9SxghpRix15w+QfMP2DR+O1wg/KSGOrIhRAs=; b=GIkbx8t6ayJFzeC113sB0HM6aPI/UwgZCdsjf9mIVSrqwTynlvXfniEzOBuGDvS8Ho bQJB5GN5qZmhNYpVQY9UdSKqn9VDtJDTNOX5tnANwYXiUwXTb061NDQMWzkX+PWjDsAi 7fbMuQ3j6n48KAph39mmnYL22gaD6Bztcbd3SKVFnfE+RZLX5EUAr9i4AWgAliT9CTCX 1z18wWS+c0kp6kkfS9i4MRuCpYF4B0FT7GOxndlxnXvpU3pYYfqS58t/kXfUgiEgdfsg dTKNkgC6UZhlxTfROxaVBok55ChfzNsfFoZHVJhhS6fFX2MyOQpvHKd3tJuxkcgqKdyo AMvw== X-Gm-Message-State: AD7BkJKp1koV2O80rmaGapGLcoVS3mUkOVB5tuoOX2VQmKelNj9dfGSJWIkTaUtBS0X7ZA== X-Received: by 10.98.93.155 with SMTP id n27mr23368890pfj.88.1457229701767; Sat, 05 Mar 2016 18:01:41 -0800 (PST) Received: from localhost ([45.32.44.20]) by smtp.gmail.com with ESMTPSA id ux2sm14942830pac.46.2016.03.05.18.01.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 05 Mar 2016 18:01:41 -0800 (PST) From: Wei Yang To: jan.kiszka@siemens.com, pbonzini@redhat.com Date: Sun, 6 Mar 2016 01:57:25 +0000 Message-Id: <1457229445-25954-1-git-send-email-richard.weiyang@gmail.com> X-Mailer: git-send-email 2.5.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2607:f8b0:400e:c00::22a Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, Wei Yang Subject: [Qemu-devel] [PATCH] kvm/irqchip: use bitmap utility for gsi tracking X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP By using utilities in bitops and bitmap, this patch tries to make it more friendly to audience. No functional change. Signed-off-by: Wei Yang --- kvm-all.c | 34 ++++++++++------------------------ 1 file changed, 10 insertions(+), 24 deletions(-) diff --git a/kvm-all.c b/kvm-all.c index bd9e764..ed3f4a2 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -90,7 +90,7 @@ struct KVMState #ifdef KVM_CAP_IRQ_ROUTING struct kvm_irq_routing *irq_routes; int nr_allocated_irq_routes; - uint32_t *used_gsi_bitmap; + unsigned long *used_gsi_bitmap; unsigned int gsi_count; QTAILQ_HEAD(msi_hashtab, KVMMSIRoute) msi_hashtab[KVM_MSI_HASHTAB_SIZE]; #endif @@ -951,12 +951,12 @@ typedef struct KVMMSIRoute { static void set_gsi(KVMState *s, unsigned int gsi) { - s->used_gsi_bitmap[gsi / 32] |= 1U << (gsi % 32); + set_bit(gsi, s->used_gsi_bitmap); } static void clear_gsi(KVMState *s, unsigned int gsi) { - s->used_gsi_bitmap[gsi / 32] &= ~(1U << (gsi % 32)); + clear_bit(gsi, s->used_gsi_bitmap); } void kvm_init_irq_routing(KVMState *s) @@ -965,17 +965,9 @@ void kvm_init_irq_routing(KVMState *s) gsi_count = kvm_check_extension(s, KVM_CAP_IRQ_ROUTING) - 1; if (gsi_count > 0) { - unsigned int gsi_bits, i; - /* Round up so we can search ints using ffs */ - gsi_bits = ALIGN(gsi_count, 32); - s->used_gsi_bitmap = g_malloc0(gsi_bits / 8); + s->used_gsi_bitmap = bitmap_new(gsi_count); s->gsi_count = gsi_count; - - /* Mark any over-allocated bits as already in use */ - for (i = gsi_count; i < gsi_bits; i++) { - set_gsi(s, i); - } } s->irq_routes = g_malloc0(sizeof(*s->irq_routes)); @@ -1105,9 +1097,7 @@ static void kvm_flush_dynamic_msi_routes(KVMState *s) static int kvm_irqchip_get_virq(KVMState *s) { - uint32_t *word = s->used_gsi_bitmap; - int max_words = ALIGN(s->gsi_count, 32) / 32; - int i, zeroes; + int next_virq; /* * PIC and IOAPIC share the first 16 GSI numbers, thus the available @@ -1120,16 +1110,12 @@ static int kvm_irqchip_get_virq(KVMState *s) } /* Return the lowest unused GSI in the bitmap */ - for (i = 0; i < max_words; i++) { - zeroes = ctz32(~word[i]); - if (zeroes == 32) { - continue; - } - - return zeroes + i * 32; + next_virq = find_first_zero_bit(s->used_gsi_bitmap, s->gsi_count); + if (next_virq >= s->gsi_count) { + return -ENOSPC; + } else { + return next_virq; } - return -ENOSPC; - } static KVMMSIRoute *kvm_lookup_msi_route(KVMState *s, MSIMessage msg)