From patchwork Mon Jul 25 12:21:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 1660327 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=gbUgGS0l; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4LrzhR6LMSz9sGH for ; Mon, 25 Jul 2022 22:22:47 +1000 (AEST) Received: from localhost ([::1]:52264 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oFx6j-0002aM-IV for incoming@patchwork.ozlabs.org; Mon, 25 Jul 2022 08:22:45 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48564) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFx5X-0002XV-SV for qemu-devel@nongnu.org; Mon, 25 Jul 2022 08:21:33 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:39497) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFx5U-00061a-0K for qemu-devel@nongnu.org; Mon, 25 Jul 2022 08:21:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658751687; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xl16RQ27IbssBeTxi2z23S4vpV8WJZdQC/pP649MYjo=; b=gbUgGS0lYulxZj8dttigI2cBcbm7X/zCqixcE0Ng47fGYZ8JJQtM4yKoCtWLAEij6UMSAV EF5BN7WgzhP6ku72adczoeSx9u0G6yd1Dmz6f1lE68ohxf3A5DPWXggqTL7x0agAidANd0 oyTBhQHURt68TI1ey/TyZuR9H6SPEXQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-457-zw5qGrT8MPGuOR0wh5cT5Q-1; Mon, 25 Jul 2022 08:21:26 -0400 X-MC-Unique: zw5qGrT8MPGuOR0wh5cT5Q-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C44628853AB; Mon, 25 Jul 2022 12:21:23 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 753E618EB5; Mon, 25 Jul 2022 12:21:23 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Cc: Kevin Wolf , Hanna Reitz , Paolo Bonzini , John Snow , Vladimir Sementsov-Ogievskiy , Markus Armbruster , Stefan Hajnoczi , qemu-devel@nongnu.org, Emanuele Giuseppe Esposito Subject: [PATCH v2 03/11] bdrv_change_aio_context: use hash table instead of list of visited nodes Date: Mon, 25 Jul 2022 08:21:12 -0400 Message-Id: <20220725122120.309236-4-eesposit@redhat.com> In-Reply-To: <20220725122120.309236-1-eesposit@redhat.com> References: <20220725122120.309236-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Minor performance improvement, but given that we have hash tables available, avoid iterating in the visited nodes list every time just to check if a node has been already visited. The data structure is not actually a proper hash map, but an hash set, as we are just adding nodes and not key,value pairs. Suggested-by: Hanna Reitz Signed-off-by: Emanuele Giuseppe Esposito Reviewed-by: Kevin Wolf --- block.c | 28 ++++++++++++++++------------ include/block/block-global-state.h | 2 +- include/block/block_int-common.h | 3 ++- 3 files changed, 19 insertions(+), 14 deletions(-) diff --git a/block.c b/block.c index c80e49009a..c02a628336 100644 --- a/block.c +++ b/block.c @@ -109,7 +109,7 @@ static void bdrv_reopen_abort(BDRVReopenState *reopen_state); static bool bdrv_backing_overridden(BlockDriverState *bs); static bool bdrv_change_aio_context(BlockDriverState *bs, AioContext *ctx, - GSList **visited, Transaction *tran, + GHashTable *visited, Transaction *tran, Error **errp); /* If non-zero, use only whitelisted block drivers */ @@ -7444,14 +7444,15 @@ typedef struct BdrvStateSetAioContext { } BdrvStateSetAioContext; static bool bdrv_parent_change_aio_context(BdrvChild *c, AioContext *ctx, - GSList **visited, Transaction *tran, + GHashTable *visited, + Transaction *tran, Error **errp) { GLOBAL_STATE_CODE(); - if (g_slist_find(*visited, c)) { + if (g_hash_table_contains(visited, c)) { return true; } - *visited = g_slist_prepend(*visited, c); + g_hash_table_add(visited, c); /* * A BdrvChildClass that doesn't handle AioContext changes cannot @@ -7482,14 +7483,14 @@ bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, } bool bdrv_child_change_aio_context(BdrvChild *c, AioContext *ctx, - GSList **visited, Transaction *tran, + GHashTable *visited, Transaction *tran, Error **errp) { GLOBAL_STATE_CODE(); - if (g_slist_find(*visited, c)) { + if (g_hash_table_contains(visited, c)) { return true; } - *visited = g_slist_prepend(*visited, c); + g_hash_table_add(visited, c); return bdrv_change_aio_context(c->bs, ctx, visited, tran, errp); } @@ -7561,7 +7562,7 @@ static TransactionActionDrv set_aio_context = { * responsible for freeing the list afterwards. */ static bool bdrv_change_aio_context(BlockDriverState *bs, AioContext *ctx, - GSList **visited, Transaction *tran, + GHashTable *visited, Transaction *tran, Error **errp) { BdrvChild *c; @@ -7646,16 +7647,19 @@ int bdrv_child_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, BdrvChild *ignore_child, Error **errp) { Transaction *tran; - GSList *visited; + GHashTable *visited; int ret; AioContext *old_context = bdrv_get_aio_context(bs); GLOBAL_STATE_CODE(); /* Recursion phase: go through all nodes of the graph */ tran = tran_new(); - visited = ignore_child ? g_slist_prepend(NULL, ignore_child) : NULL; - ret = bdrv_change_aio_context(bs, ctx, &visited, tran, errp); - g_slist_free(visited); + visited = g_hash_table_new(NULL, NULL); + if (ignore_child) { + g_hash_table_add(visited, ignore_child); + } + ret = bdrv_change_aio_context(bs, ctx, visited, tran, errp); + g_hash_table_destroy(visited); /* Linear phase: go through all callbacks collected in the transaction */ diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index fdcb81a175..ceecf0aa8e 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -230,7 +230,7 @@ bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, AioContext *bdrv_child_get_parent_aio_context(BdrvChild *c); bool bdrv_child_change_aio_context(BdrvChild *c, AioContext *ctx, - GSList **visited, Transaction *tran, + GHashTable *visited, Transaction *tran, Error **errp); int bdrv_child_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, BdrvChild *ignore_child, Error **errp); diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index 43828cf74f..c639873487 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -897,7 +897,8 @@ struct BdrvChildClass { void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore); bool (*change_aio_ctx)(BdrvChild *child, AioContext *ctx, - GSList **visited, Transaction *tran, Error **errp); + GHashTable *visited, Transaction *tran, + Error **errp); AioContext *(*get_parent_aio_context)(BdrvChild *child);