From patchwork Fri Dec 16 14:58:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juergen Gross X-Patchwork-Id: 13075077 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 549ECC4332F for ; Fri, 16 Dec 2022 14:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231288AbiLPO7F (ORCPT ); Fri, 16 Dec 2022 09:59:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231289AbiLPO6o (ORCPT ); Fri, 16 Dec 2022 09:58:44 -0500 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 280546036B; Fri, 16 Dec 2022 06:58:38 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id C4D0734319; Fri, 16 Dec 2022 14:58:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1671202716; h=from:from:reply-to: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=x36AuY9fdrueTpOox7l4aH9J7+eTrfGAHM9OlY2CQHU=; b=SpGCTUY9+p3OSfiSSP0kSXj9iihsB9mtnEn6ajE8dHqS/FXFp5u52Ir2MnnMN0A0cCXhCR /nXL0RpYDQ5qQuU2FRxvLaqebBWdRkl6u08yKZs+ggqLcW7K2N/SgFEgEOusM82T6Xk9rN 7dJmWlPYvDa0JU/uSa6/ZfB3W7Wi8OE= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 93C0B138FD; Fri, 16 Dec 2022 14:58:36 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id ccTCIpyHnGPPeAAAMHmgww (envelope-from ); Fri, 16 Dec 2022 14:58:36 +0000 From: Juergen Gross To: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org Cc: Juergen Gross , =?utf-8?q?Roger_Pau_Monn=C3=A9?= , Jens Axboe , xen-devel@lists.xenproject.org Subject: [PATCH 3/4] xen/blkback: simplify free_persistent_gnts() interface Date: Fri, 16 Dec 2022 15:58:15 +0100 Message-Id: <20221216145816.27374-4-jgross@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20221216145816.27374-1-jgross@suse.com> References: <20221216145816.27374-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org The interface of free_persistent_gnts() can be simplified, as there is only a single caller of free_persistent_gnts() and the 2nd and 3rd parameters are easily obtainable via the ring pointer, which is passed as the first parameter anyway. Signed-off-by: Juergen Gross --- drivers/block/xen-blkback/blkback.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 6e2163aaf362..243712b59a05 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -239,9 +239,9 @@ static void put_persistent_gnt(struct xen_blkif_ring *ring, atomic_dec(&ring->persistent_gnt_in_use); } -static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root, - unsigned int num) +static void free_persistent_gnts(struct xen_blkif_ring *ring) { + struct rb_root *root = &ring->persistent_gnts; struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; @@ -249,6 +249,9 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro int segs_to_unmap = 0; struct gntab_unmap_queue_data unmap_data; + if (RB_EMPTY_ROOT(root)) + return; + unmap_data.pages = pages; unmap_data.unmap_ops = unmap; unmap_data.kunmap_ops = NULL; @@ -277,9 +280,11 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro rb_erase(&persistent_gnt->node, root); kfree(persistent_gnt); - num--; + ring->persistent_gnt_c--; } - BUG_ON(num != 0); + + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); + BUG_ON(ring->persistent_gnt_c != 0); } void xen_blkbk_unmap_purged_grants(struct work_struct *work) @@ -631,12 +636,7 @@ int xen_blkif_schedule(void *arg) void xen_blkbk_free_caches(struct xen_blkif_ring *ring) { /* Free all persistent grant pages */ - if (!RB_EMPTY_ROOT(&ring->persistent_gnts)) - free_persistent_gnts(ring, &ring->persistent_gnts, - ring->persistent_gnt_c); - - BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); - ring->persistent_gnt_c = 0; + free_persistent_gnts(ring); /* Since we are shutting down remove all pages from the buffer */ gnttab_page_cache_shrink(&ring->free_pages, 0 /* All */);