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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D68FC43444 for ; Thu, 10 Jan 2019 09:51:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE8A02183F for ; Thu, 10 Jan 2019 09:51:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547113898; bh=oWUTePOMtpHziylhL0nsoA2h1dUu5DecFxkNSlxT8M8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=K1xER3RuwzF8WVBVy2rwz9BeOKCTXeCHja1GbKjxgaWBu4DfmfKHzGRf4StKF8Ru3 w9d85oMtvM6bEK8YOM7MvFpkCvNODcS9xAvcC1ewzgDy6JonBd6pRLO5cQw20MjA/4 XQID33k89wVTHfO1y/NxpGUC0RNEJcSOQOW03vF4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728104AbfAJJvh (ORCPT ); Thu, 10 Jan 2019 04:51:37 -0500 Received: from mx2.suse.de ([195.135.220.15]:33546 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727916AbfAJJvg (ORCPT ); Thu, 10 Jan 2019 04:51:36 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 07F6AAFFC; Thu, 10 Jan 2019 09:51:34 +0000 (UTC) Date: Thu, 10 Jan 2019 10:51:31 +0100 From: Michal Hocko To: Arun KS Cc: arunks.linux@gmail.com, alexander.h.duyck@linux.intel.com, akpm@linux-foundation.org, vbabka@suse.cz, osalvador@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, getarunks@gmail.com Subject: Re: [PATCH v9] mm/page_alloc.c: memory_hotplug: free pages as higher order Message-ID: <20190110095131.GJ31793@dhcp22.suse.cz> References: <1547098543-26452-1-git-send-email-arunks@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1547098543-26452-1-git-send-email-arunks@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 10-01-19 11:05:43, Arun KS wrote: > When freeing pages are done with higher order, time spent on coalescing > pages by buddy allocator can be reduced. With section size of 256MB, hot > add latency of a single section shows improvement from 50-60 ms to less > than 1 ms, hence improving the hot add latency by 60 times. Modify > external providers of online callback to align with the change. > > Signed-off-by: Arun KS > Acked-by: Michal Hocko JFTR. I have mentioned that previously but let me repeat. You should be dropping any acks/reviewed-bys when making any non trivial changes to a patch and reposting. Nevertheless, the patch still looks ok so my Acked-by still applies to the core MM parts but do not assume that in future please. > Reviewed-by: Oscar Salvador > --- > Changes since v8: > - Remove return type change for online_page_callback. > - Use consistent names for external online_page providers. > - Fix onlined_pages accounting. > > Changes since v7: > - Rebased to 5.0-rc1. > - Fixed onlined_pages accounting. > - Added comment for return value of online_page_callback. > - Renamed xen_bring_pgs_online to xen_online_pages. > > Changes since v6: > - Rebased to 4.20 > - Changelog updated. > - No improvement seen on arm64, hence removed removal of prefetch. > > Changes since v5: > - Rebased to 4.20-rc1. > - Changelog updated. > > Changes since v4: > - As suggested by Michal Hocko, > - Simplify logic in online_pages_block() by using get_order(). > - Seperate out removal of prefetch from __free_pages_core(). > > Changes since v3: > - Renamed _free_pages_boot_core -> __free_pages_core. > - Removed prefetch from __free_pages_core. > - Removed xen_online_page(). > > Changes since v2: > - Reuse code from __free_pages_boot_core(). > > Changes since v1: > - Removed prefetch(). > > Changes since RFC: > - Rebase. > - As suggested by Michal Hocko remove pages_per_block. > - Modifed external providers of online_page_callback. > > v8: https://lore.kernel.org/patchwork/patch/1030332/ > v7: https://lore.kernel.org/patchwork/patch/1028908/ > v6: https://lore.kernel.org/patchwork/patch/1007253/ > v5: https://lore.kernel.org/patchwork/patch/995739/ > v4: https://lore.kernel.org/patchwork/patch/995111/ > v3: https://lore.kernel.org/patchwork/patch/992348/ > v2: https://lore.kernel.org/patchwork/patch/991363/ > v1: https://lore.kernel.org/patchwork/patch/989445/ > RFC: https://lore.kernel.org/patchwork/patch/984754/ > --- > --- > drivers/hv/hv_balloon.c | 4 ++-- > drivers/xen/balloon.c | 15 ++++++++++----- > include/linux/memory_hotplug.h | 2 +- > mm/internal.h | 1 + > mm/memory_hotplug.c | 37 +++++++++++++++++++++++++------------ > mm/page_alloc.c | 8 ++++---- > 6 files changed, 43 insertions(+), 24 deletions(-) > > diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c > index 5301fef..55d79f8 100644 > --- a/drivers/hv/hv_balloon.c > +++ b/drivers/hv/hv_balloon.c > @@ -771,7 +771,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size, > } > } > > -static void hv_online_page(struct page *pg) > +static void hv_online_page(struct page *pg, unsigned int order) > { > struct hv_hotadd_state *has; > unsigned long flags; > @@ -783,7 +783,7 @@ static void hv_online_page(struct page *pg) > if ((pfn < has->start_pfn) || (pfn >= has->end_pfn)) > continue; > > - hv_page_online_one(has, pg); > + hv_bring_pgs_online(has, pfn, (1UL << order)); > break; > } > spin_unlock_irqrestore(&dm_device.ha_lock, flags); > diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c > index ceb5048..d107447 100644 > --- a/drivers/xen/balloon.c > +++ b/drivers/xen/balloon.c > @@ -369,14 +369,19 @@ static enum bp_state reserve_additional_memory(void) > return BP_ECANCELED; > } > > -static void xen_online_page(struct page *page) > +static void xen_online_page(struct page *page, unsigned int order) > { > - __online_page_set_limits(page); > + unsigned long i, size = (1 << order); > + unsigned long start_pfn = page_to_pfn(page); > + struct page *p; > > + pr_debug("Online %lu pages starting at pfn 0x%lx\n", size, start_pfn); > mutex_lock(&balloon_mutex); > - > - __balloon_append(page); > - > + for (i = 0; i < size; i++) { > + p = pfn_to_page(start_pfn + i); > + __online_page_set_limits(p); > + __balloon_append(p); > + } > mutex_unlock(&balloon_mutex); > } > > diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > index 07da5c6..e368730 100644 > --- a/include/linux/memory_hotplug.h > +++ b/include/linux/memory_hotplug.h > @@ -87,7 +87,7 @@ extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, > unsigned long *valid_start, unsigned long *valid_end); > extern void __offline_isolated_pages(unsigned long, unsigned long); > > -typedef void (*online_page_callback_t)(struct page *page); > +typedef void (*online_page_callback_t)(struct page *page, unsigned int order); > > extern int set_online_page_callback(online_page_callback_t callback); > extern int restore_online_page_callback(online_page_callback_t callback); > diff --git a/mm/internal.h b/mm/internal.h > index f4a7bb0..536bc2a 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -163,6 +163,7 @@ static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, > extern int __isolate_free_page(struct page *page, unsigned int order); > extern void memblock_free_pages(struct page *page, unsigned long pfn, > unsigned int order); > +extern void __free_pages_core(struct page *page, unsigned int order); > extern void prep_compound_page(struct page *page, unsigned int order); > extern void post_alloc_hook(struct page *page, unsigned int order, > gfp_t gfp_flags); > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index b9a667d..77dff24 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -47,7 +47,7 @@ > * and restore_online_page_callback() for generic callback restore. > */ > > -static void generic_online_page(struct page *page); > +static void generic_online_page(struct page *page, unsigned int order); > > static online_page_callback_t online_page_callback = generic_online_page; > static DEFINE_MUTEX(online_page_callback_lock); > @@ -656,26 +656,39 @@ void __online_page_free(struct page *page) > } > EXPORT_SYMBOL_GPL(__online_page_free); > > -static void generic_online_page(struct page *page) > +static void generic_online_page(struct page *page, unsigned int order) > { > - __online_page_set_limits(page); > - __online_page_increment_counters(page); > - __online_page_free(page); > + __free_pages_core(page, order); > + totalram_pages_add(1UL << order); > +#ifdef CONFIG_HIGHMEM > + if (PageHighMem(page)) > + totalhigh_pages_add(1UL << order); > +#endif > +} > + > +static int online_pages_blocks(unsigned long start, unsigned long nr_pages) > +{ > + unsigned long end = start + nr_pages; > + int order, ret, onlined_pages = 0; > + > + while (start < end) { > + order = min(MAX_ORDER - 1, > + get_order(PFN_PHYS(end) - PFN_PHYS(start))); > + (*online_page_callback)(pfn_to_page(start), order); > + > + onlined_pages += (1UL << order); > + start += (1UL << order); > + } > + return onlined_pages; > } > > static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, > void *arg) > { > - unsigned long i; > unsigned long onlined_pages = *(unsigned long *)arg; > - struct page *page; > > if (PageReserved(pfn_to_page(start_pfn))) > - for (i = 0; i < nr_pages; i++) { > - page = pfn_to_page(start_pfn + i); > - (*online_page_callback)(page); > - onlined_pages++; > - } > + onlined_pages += online_pages_blocks(start_pfn, nr_pages); > > online_mem_sections(start_pfn, start_pfn + nr_pages); > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index d295c9b..883212a 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1303,7 +1303,7 @@ static void __free_pages_ok(struct page *page, unsigned int order) > local_irq_restore(flags); > } > > -static void __init __free_pages_boot_core(struct page *page, unsigned int order) > +void __free_pages_core(struct page *page, unsigned int order) > { > unsigned int nr_pages = 1 << order; > struct page *p = page; > @@ -1382,7 +1382,7 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, > { > if (early_page_uninitialised(pfn)) > return; > - return __free_pages_boot_core(page, order); > + __free_pages_core(page, order); > } > > /* > @@ -1472,14 +1472,14 @@ static void __init deferred_free_range(unsigned long pfn, > if (nr_pages == pageblock_nr_pages && > (pfn & (pageblock_nr_pages - 1)) == 0) { > set_pageblock_migratetype(page, MIGRATE_MOVABLE); > - __free_pages_boot_core(page, pageblock_order); > + __free_pages_core(page, pageblock_order); > return; > } > > for (i = 0; i < nr_pages; i++, page++, pfn++) { > if ((pfn & (pageblock_nr_pages - 1)) == 0) > set_pageblock_migratetype(page, MIGRATE_MOVABLE); > - __free_pages_boot_core(page, 0); > + __free_pages_core(page, 0); > } > } > > -- > 1.9.1 -- Michal Hocko SUSE Labs