From patchwork Thu Mar 30 11:36:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 13194000 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 6A7E3C77B60 for ; Thu, 30 Mar 2023 11:38:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231688AbjC3Li0 (ORCPT ); Thu, 30 Mar 2023 07:38:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231657AbjC3LiV (ORCPT ); Thu, 30 Mar 2023 07:38:21 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE9C56A7F for ; Thu, 30 Mar 2023 04:36:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1680176216; 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=cMvtAiZrEHr/RuIr5EK3Qcf9yPL0DeQpzw5d26wmtC4=; b=VnxVlDK1+obyJCE1HGKZLPeMbWuSVA5PCswgluKcF+KZF6lUMcM6OtrNyIuDRkj+lH/Suu lssFFBIlGj6rIDJFZ9fA5K8xXPNNixAS/wt2lJYvVsyvGB2LMuX56Ze4bodgnyYOSBSvBV OevpIVlCtJhDJKb44Keq0AFt4YK6EOs= 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-528-PTeUdGuBPCWYIzRDacSIJA-1; Thu, 30 Mar 2023 07:36:54 -0400 X-MC-Unique: PTeUdGuBPCWYIzRDacSIJA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5717585A588; Thu, 30 Mar 2023 11:36:54 +0000 (UTC) Received: from localhost (ovpn-8-19.pek2.redhat.com [10.72.8.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 675CE14171BE; Thu, 30 Mar 2023 11:36:52 +0000 (UTC) From: Ming Lei To: Jens Axboe , io-uring@vger.kernel.org, linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Miklos Szeredi , ZiyangZhang , Xiaoguang Wang , Bernd Schubert , Pavel Begunkov , Stefan Hajnoczi , Dan Williams , Ming Lei Subject: [PATCH V6 02/17] io_uring: use ctx->cached_sq_head to calculate left sqes Date: Thu, 30 Mar 2023 19:36:15 +0800 Message-Id: <20230330113630.1388860-3-ming.lei@redhat.com> In-Reply-To: <20230330113630.1388860-1-ming.lei@redhat.com> References: <20230330113630.1388860-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Use ctx->cached_sq_head to calculate 'left' sqes, and prepare for supporting fused requests, which need to get req/sqe in its own ->prep() callback. ctx->cached_sq_head should always be cached or to be fetched, so this change is just fine. Signed-off-by: Ming Lei --- io_uring/io_uring.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 693558c4b10b..25a940f0ab68 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -2429,15 +2429,16 @@ int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) __must_hold(&ctx->uring_lock) { unsigned int entries = io_sqring_entries(ctx); - unsigned int left; + unsigned old_head = ctx->cached_sq_head; + unsigned int left = 0; int ret; if (unlikely(!entries)) return 0; /* make sure SQ entry isn't read before tail */ - ret = left = min3(nr, ctx->sq_entries, entries); - io_get_task_refs(left); - io_submit_state_start(&ctx->submit_state, left); + ret = min3(nr, ctx->sq_entries, entries); + io_get_task_refs(ret); + io_submit_state_start(&ctx->submit_state, ret); do { const struct io_uring_sqe *sqe; @@ -2456,11 +2457,12 @@ int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) */ if (unlikely(io_submit_sqe(ctx, req, sqe)) && !(ctx->flags & IORING_SETUP_SUBMIT_ALL)) { - left--; + left = 1; break; } - } while (--left); + } while ((ctx->cached_sq_head - old_head) < ret); + left = ret - (ctx->cached_sq_head - old_head) - left; if (unlikely(left)) { ret -= left; /* try again if it submitted nothing and can't allocate a req */