From mboxrd@z Thu Jan 1 00:00:00 1970 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 81BD8EE49A6 for ; Mon, 21 Aug 2023 20:52:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231473AbjHUUwo (ORCPT ); Mon, 21 Aug 2023 16:52:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47716 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231493AbjHUUwc (ORCPT ); Mon, 21 Aug 2023 16:52:32 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B58F81721 for ; Mon, 21 Aug 2023 13:44:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=RORJVnZ1xjomMTeygi3JJ1E6/B1esghHOmLJuCDuVL8=; b=cX48794hHeiyAzu9fcQmsTqm/r aqdYpWMbkTSg7sdRenY7DY184Sjqx0L5TE1lRgR1Rv/aCmpiho/0J8NfdRRgDvgFHaQ9sh85P0saE Ey1GDns++lTylnBp8OVqiMfqhFMzLA0fpZGEodGibshcHZBSYp3j6aPLIDFwP1ocmxTHjfQXSr6px xr/QshlBPusGF0zTRlEZH8lHdsFiiY9YmUKnFUHdiJr3VPUBOpZfpiAhZnQ8FyqDrjkrlCHWc+dgm 7+hR/W6e6bBmn7K8tUqHbHnagtZH6cUOlrhdg4Auy7hyJ8bNsFbqaLdZ3mv0bZKbpg7B9GN6tG/LJ C4P1H2Sg==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qYBlE-00CL08-JJ; Mon, 21 Aug 2023 20:44:28 +0000 From: "Matthew Wilcox (Oracle)" To: Mateusz Guzik , linux-kernel@vger.kernel.org, dennis@kernel.org, tj@kernel.org, cl@linux.com, akpm@linux-foundation.org, shakeelb@google.com, linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" Subject: [PATCH 3/7] mm: Add free_unref_folios() Date: Mon, 21 Aug 2023 21:44:21 +0100 Message-Id: <20230821204425.2940496-3-willy@infradead.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20230821204425.2940496-1-willy@infradead.org> References: <20230821204425.2940496-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Iterate over a folio_batch rather than a linked list. This is easier for the CPU to prefetch and has a batch count naturally built in so we don't need to track it. Signed-off-by: Matthew Wilcox (Oracle) --- mm/internal.h | 5 +++-- mm/page_alloc.c | 59 ++++++++++++++++++++++++++++++------------------- 2 files changed, 39 insertions(+), 25 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 5c777b6779fa..3e6b448e7d63 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -440,8 +440,9 @@ extern void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags); extern int user_min_free_kbytes; -extern void free_unref_page(struct page *page, unsigned int order); -extern void free_unref_page_list(struct list_head *list); +void free_unref_page(struct page *page, unsigned int order); +void free_unref_folios(struct folio_batch *fbatch); +void free_unref_page_list(struct list_head *list); extern void zone_pcp_reset(struct zone *zone); extern void zone_pcp_disable(struct zone *zone); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2f2185929fcb..4354938ca3b0 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include #include @@ -2493,24 +2494,21 @@ void free_unref_page(struct page *page, unsigned int order) } /* - * Free a list of 0-order pages + * Free a batch of 0-order pages */ -void free_unref_page_list(struct list_head *list) +void free_unref_folios(struct folio_batch *folios) { unsigned long __maybe_unused UP_flags; - struct folio *folio, *next; struct per_cpu_pages *pcp = NULL; struct zone *locked_zone = NULL; - int batch_count = 0; - int migratetype; + int i, j, migratetype; - /* Prepare pages for freeing */ - list_for_each_entry_safe(folio, next, list, lru) { + /* Prepare folios for freeing */ + for (i = 0, j = 0; i < folios->nr; i++) { + struct folio *folio = folios->folios[i]; unsigned long pfn = folio_pfn(folio); - if (!free_unref_page_prepare(&folio->page, pfn, 0)) { - list_del(&folio->lru); + if (!free_unref_page_prepare(&folio->page, pfn, 0)) continue; - } /* * Free isolated pages directly to the allocator, see @@ -2518,34 +2516,31 @@ void free_unref_page_list(struct list_head *list) */ migratetype = get_pcppage_migratetype(&folio->page); if (unlikely(is_migrate_isolate(migratetype))) { - list_del(&folio->lru); free_one_page(folio_zone(folio), &folio->page, pfn, 0, migratetype, FPI_NONE); continue; } + if (j != i) + folios->folios[j] = folio; + j++; } + folios->nr = j; - list_for_each_entry_safe(folio, next, list, lru) { + for (i = 0; i < folios->nr; i++) { + struct folio *folio = folios->folios[i]; struct zone *zone = folio_zone(folio); - list_del(&folio->lru); migratetype = get_pcppage_migratetype(&folio->page); - /* - * Either different zone requiring a different pcp lock or - * excessive lock hold times when freeing a large list of - * folios. - */ - if (zone != locked_zone || batch_count == SWAP_CLUSTER_MAX) { + /* Different zone requires a different pcp lock */ + if (zone != locked_zone) { if (pcp) { pcp_spin_unlock(pcp); pcp_trylock_finish(UP_flags); } - batch_count = 0; - /* - * trylock is necessary as folios may be getting freed + * trylock is necessary as pages may be getting freed * from IRQ or SoftIRQ context after an IO completion. */ pcp_trylock_prepare(UP_flags); @@ -2570,7 +2565,6 @@ void free_unref_page_list(struct list_head *list) trace_mm_page_free_batched(&folio->page); free_unref_page_commit(zone, pcp, &folio->page, migratetype, 0); - batch_count++; } if (pcp) { @@ -2579,6 +2573,25 @@ void free_unref_page_list(struct list_head *list) } } +void free_unref_page_list(struct list_head *list) +{ + struct folio_batch fbatch; + + folio_batch_init(&fbatch); + while (!list_empty(list)) { + struct folio *folio = list_first_entry(list, struct folio, lru); + + list_del(&folio->lru); + if (folio_batch_add(&fbatch, folio) > 0) + continue; + free_unref_folios(&fbatch); + fbatch.nr = 0; + } + + if (fbatch.nr) + free_unref_folios(&fbatch); +} + /* * split_page takes a non-compound higher-order page, and splits it into * n (1<