From patchwork Mon Jun 27 13:35:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Xu X-Patchwork-Id: 12896654 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BDD71C43334 for ; Mon, 27 Jun 2022 13:36:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235949AbiF0NgP (ORCPT ); Mon, 27 Jun 2022 09:36:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44240 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234557AbiF0NgP (ORCPT ); Mon, 27 Jun 2022 09:36:15 -0400 Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FF246362 for ; Mon, 27 Jun 2022 06:36:14 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1656336973; 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=21GvqUh+eSxTwP7XE55aCv2mhTFoxlA4FnB4sAjQh+s=; b=BgPsTRcNrFcEgbyuW29P9KFbgM+a9001rA2WKXtw3rQP8PYr2qWvV5+XBO/VV2pMm9RgKe P6U7LMlWSlhnldOMGKnnKtldRinnnWJL6e09PZBqIkl+9Z8A7HPZj1HqzQQATV54ACHNFk Rz6+dsjpZhEQw7Wct/pUeQioR09+lyU= From: Hao Xu To: io-uring@vger.kernel.org Cc: Jens Axboe , Pavel Begunkov Subject: [PATCH 08/11] io-wq: batch the handling of fixed worker private works Date: Mon, 27 Jun 2022 21:35:38 +0800 Message-Id: <20220627133541.15223-9-hao.xu@linux.dev> In-Reply-To: <20220627133541.15223-1-hao.xu@linux.dev> References: <20220627133541.15223-1-hao.xu@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org From: Hao Xu Reduce acct->lock contension by batching the handling of private work list for fixed_workers. Signed-off-by: Hao Xu --- io_uring/io-wq.c | 42 +++++++++++++++++++++++++++++++++--------- io_uring/io-wq.h | 5 +++++ 2 files changed, 38 insertions(+), 9 deletions(-) diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c index c87ba38f27b1..ce754c78ecac 100644 --- a/io_uring/io-wq.c +++ b/io_uring/io-wq.c @@ -545,8 +545,23 @@ static bool io_wait_on_hash(struct io_wqe *wqe, unsigned int hash) return ret; } +static inline void conditional_acct_lock(struct io_wqe_acct *acct, + bool needs_lock) +{ + if (needs_lock) + raw_spin_lock(&acct->lock); +} + +static inline void conditional_acct_unlock(struct io_wqe_acct *acct, + bool needs_lock) +{ + if (needs_lock) + raw_spin_unlock(&acct->lock); +} + static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, - struct io_worker *worker) + struct io_worker *worker, + bool needs_lock) __must_hold(acct->lock) { struct io_wq_work_node *node, *prev; @@ -554,6 +569,7 @@ static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, unsigned int stall_hash = -1U; struct io_wqe *wqe = worker->wqe; + conditional_acct_lock(acct, needs_lock); wq_list_for_each(node, prev, &acct->work_list) { unsigned int hash; @@ -562,6 +578,7 @@ static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, /* not hashed, can run anytime */ if (!io_wq_is_hashed(work)) { wq_list_del(&acct->work_list, node, prev); + conditional_acct_unlock(acct, needs_lock); return work; } @@ -573,6 +590,7 @@ static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, if (!test_and_set_bit(hash, &wqe->wq->hash->map)) { wqe->hash_tail[hash] = NULL; wq_list_cut(&acct->work_list, &tail->list, prev); + conditional_acct_unlock(acct, needs_lock); return work; } if (stall_hash == -1U) @@ -589,15 +607,16 @@ static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, * work being added and clearing the stalled bit. */ set_bit(IO_ACCT_STALLED_BIT, &acct->flags); - raw_spin_unlock(&acct->lock); + conditional_acct_unlock(acct, needs_lock); unstalled = io_wait_on_hash(wqe, stall_hash); - raw_spin_lock(&acct->lock); + conditional_acct_lock(acct, needs_lock); if (unstalled) { clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); if (wq_has_sleeper(&wqe->wq->hash->wait)) wake_up(&wqe->wq->hash->wait); } } + conditional_acct_unlock(acct, needs_lock); return NULL; } @@ -631,7 +650,7 @@ static void io_assign_current_work(struct io_worker *worker, static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work); static void io_worker_handle_work(struct io_worker *worker, - struct io_wqe_acct *acct) + struct io_wqe_acct *acct, bool needs_lock) { struct io_wqe *wqe = worker->wqe; struct io_wq *wq = wqe->wq; @@ -647,9 +666,7 @@ static void io_worker_handle_work(struct io_worker *worker, * can't make progress, any work completion or insertion will * clear the stalled flag. */ - raw_spin_lock(&acct->lock); - work = io_get_next_work(acct, worker); - raw_spin_unlock(&acct->lock); + work = io_get_next_work(acct, worker, needs_lock); if (work) { __io_worker_busy(wqe, worker); @@ -706,12 +723,19 @@ static void io_worker_handle_work(struct io_worker *worker, static inline void io_worker_handle_private_work(struct io_worker *worker) { - io_worker_handle_work(worker, &worker->acct); + struct io_wqe_acct acct; + + raw_spin_lock(&worker->acct.lock); + acct = worker->acct; + wq_list_clean(&worker->acct.work_list); + worker->acct.nr_works = 0; + raw_spin_unlock(&worker->acct.lock); + io_worker_handle_work(worker, &acct, false); } static inline void io_worker_handle_public_work(struct io_worker *worker) { - io_worker_handle_work(worker, io_wqe_get_acct(worker)); + io_worker_handle_work(worker, io_wqe_get_acct(worker), true); } static int io_wqe_worker(void *data) diff --git a/io_uring/io-wq.h b/io_uring/io-wq.h index 10b80ef78bb8..78efbb8c53f0 100644 --- a/io_uring/io-wq.h +++ b/io_uring/io-wq.h @@ -32,6 +32,11 @@ enum io_wq_cancel { (list)->first = NULL; \ } while (0) +static inline void wq_list_clean(struct io_wq_work_list *list) +{ + list->first = list->last = NULL; +} + static inline void wq_list_add_after(struct io_wq_work_node *node, struct io_wq_work_node *pos, struct io_wq_work_list *list)