From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755134AbeE3Ec3 (ORCPT ); Wed, 30 May 2018 00:32:29 -0400 Received: from mx2.suse.de ([195.135.220.15]:44137 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750737AbeE3EcZ (ORCPT ); Wed, 30 May 2018 00:32:25 -0400 Subject: Re: [PATCH 2/8] xen/balloon: Move common memory reservation routines to a module To: Oleksandr Andrushchenko , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com Cc: daniel.vetter@intel.com, dongwon.kim@intel.com, matthew.d.roper@intel.com, Oleksandr Andrushchenko References: <20180525153331.31188-1-andr2000@gmail.com> <20180525153331.31188-3-andr2000@gmail.com> From: Juergen Gross Openpgp: preference=signencrypt Autocrypt: addr=jgross@suse.com; prefer-encrypt=mutual; keydata= xsBNBFOMcBYBCACgGjqjoGvbEouQZw/ToiBg9W98AlM2QHV+iNHsEs7kxWhKMjrioyspZKOB ycWxw3ie3j9uvg9EOB3aN4xiTv4qbnGiTr3oJhkB1gsb6ToJQZ8uxGq2kaV2KL9650I1SJve dYm8Of8Zd621lSmoKOwlNClALZNew72NjJLEzTalU1OdT7/i1TXkH09XSSI8mEQ/ouNcMvIJ NwQpd369y9bfIhWUiVXEK7MlRgUG6MvIj6Y3Am/BBLUVbDa4+gmzDC9ezlZkTZG2t14zWPvx XP3FAp2pkW0xqG7/377qptDmrk42GlSKN4z76ELnLxussxc7I2hx18NUcbP8+uty4bMxABEB AAHNHkp1ZXJnZW4gR3Jvc3MgPGpncm9zc0BzdXNlLmRlPsLAeQQTAQIAIwUCU4xw6wIbAwcL CQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJELDendYovxMvi4UH/Ri+OXlObzqMANruTd4N zmVBAZgx1VW6jLc8JZjQuJPSsd/a+bNr3BZeLV6lu4Pf1Yl2Log129EX1KWYiFFvPbIiq5M5 kOXTO8Eas4CaScCvAZ9jCMQCgK3pFqYgirwTgfwnPtxFxO/F3ZcS8jovza5khkSKL9JGq8Nk czDTruQ/oy0WUHdUr9uwEfiD9yPFOGqp4S6cISuzBMvaAiC5YGdUGXuPZKXLpnGSjkZswUzY d9BVSitRL5ldsQCg6GhDoEAeIhUC4SQnT9SOWkoDOSFRXZ+7+WIBGLiWMd+yKDdRG5RyP/8f 3tgGiB6cyuYfPDRGsELGjUaTUq3H2xZgIPfOwE0EU4xwFgEIAMsx+gDjgzAY4H1hPVXgoLK8 B93sTQFN9oC6tsb46VpxyLPfJ3T1A6Z6MVkLoCejKTJ3K9MUsBZhxIJ0hIyvzwI6aYJsnOew cCiCN7FeKJ/oA1RSUemPGUcIJwQuZlTOiY0OcQ5PFkV5YxMUX1F/aTYXROXgTmSaw0aC1Jpo w7Ss1mg4SIP/tR88/d1+HwkJDVW1RSxC1PWzGizwRv8eauImGdpNnseneO2BNWRXTJumAWDD pYxpGSsGHXuZXTPZqOOZpsHtInFyi5KRHSFyk2Xigzvh3b9WqhbgHHHE4PUVw0I5sIQt8hJq 5nH5dPqz4ITtCL9zjiJsExHuHKN3NZsAEQEAAcLAXwQYAQIACQUCU4xwFgIbDAAKCRCw3p3W KL8TL0P4B/9YWver5uD/y/m0KScK2f3Z3mXJhME23vGBbMNlfwbr+meDMrJZ950CuWWnQ+d+ Ahe0w1X7e3wuLVODzjcReQ/v7b4JD3wwHxe+88tgB9byc0NXzlPJWBaWV01yB2/uefVKryAf AHYEd0gCRhx7eESgNBe3+YqWAQawunMlycsqKa09dBDL1PFRosF708ic9346GLHRc6Vj5SRA UTHnQqLetIOXZm3a2eQ1gpQK9MmruO86Vo93p39bS1mqnLLspVrL4rhoyhsOyh0Hd28QCzpJ wKeHTd0MAWAirmewHXWPco8p1Wg+V+5xfZzuQY0f4tQxvOpXpt4gQ1817GQ5/Ed/wsDtBBgB CAAgFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAlrd8NACGwIAgQkQsN6d1ii/Ey92IAQZFggA HRYhBFMtsHpB9jjzHji4HoBcYbtP2GO+BQJa3fDQAAoJEIBcYbtP2GO+TYsA/30H/0V6cr/W V+J/FCayg6uNtm3MJLo4rE+o4sdpjjsGAQCooqffpgA+luTT13YZNV62hAnCLKXH9n3+ZAgJ RtAyDWk1B/0SMDVs1wxufMkKC3Q/1D3BYIvBlrTVKdBYXPxngcRoqV2J77lscEvkLNUGsu/z W2pf7+P3mWWlrPMJdlbax00vevyBeqtqNKjHstHatgMZ2W0CFC4hJ3YEetuRBURYPiGzuJXU pAd7a7BdsqWC4o+GTm5tnGrCyD+4gfDSpkOT53S/GNO07YkPkm/8J4OBoFfgSaCnQ1izwgJQ jIpcG2fPCI2/hxf2oqXPYbKr1v4Z1wthmoyUgGN0LPTIm+B5vdY82wI5qe9uN6UOGyTH2B3p hRQUWqCwu2sqkI3LLbTdrnyDZaixT2T0f4tyF5Lfs+Ha8xVMhIyzNb1byDI5FKCb Message-ID: Date: Wed, 30 May 2018 06:32:23 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180525153331.31188-3-andr2000@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25/05/18 17:33, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko > > Memory {increase|decrease}_reservation and VA mappings update/reset > code used in balloon driver can be made common, so other drivers can > also re-use the same functionality without open-coding. > Create a dedicated module for the shared code and export corresponding > symbols for other kernel modules. > > Signed-off-by: Oleksandr Andrushchenko > --- > drivers/xen/Makefile | 1 + > drivers/xen/balloon.c | 71 ++---------------- > drivers/xen/mem-reservation.c | 134 ++++++++++++++++++++++++++++++++++ > include/xen/mem_reservation.h | 29 ++++++++ > 4 files changed, 170 insertions(+), 65 deletions(-) > create mode 100644 drivers/xen/mem-reservation.c > create mode 100644 include/xen/mem_reservation.h Can you please name this include/xen/mem-reservation.h ? > > diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile > index 451e833f5931..3c87b0c3aca6 100644 > --- a/drivers/xen/Makefile > +++ b/drivers/xen/Makefile > @@ -2,6 +2,7 @@ > obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o > obj-$(CONFIG_X86) += fallback.o > obj-y += grant-table.o features.o balloon.o manage.o preempt.o time.o > +obj-y += mem-reservation.o > obj-y += events/ > obj-y += xenbus/ > > diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c > index 065f0b607373..57b482d67a3a 100644 > --- a/drivers/xen/balloon.c > +++ b/drivers/xen/balloon.c > @@ -71,6 +71,7 @@ > #include > #include > #include > +#include > > static int xen_hotplug_unpopulated; > > @@ -157,13 +158,6 @@ static DECLARE_DELAYED_WORK(balloon_worker, balloon_process); > #define GFP_BALLOON \ > (GFP_HIGHUSER | __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC) > > -static void scrub_page(struct page *page) > -{ > -#ifdef CONFIG_XEN_SCRUB_PAGES > - clear_highpage(page); > -#endif > -} > - > /* balloon_append: add the given page to the balloon. */ > static void __balloon_append(struct page *page) > { > @@ -463,11 +457,6 @@ static enum bp_state increase_reservation(unsigned long nr_pages) > int rc; > unsigned long i; > struct page *page; > - struct xen_memory_reservation reservation = { > - .address_bits = 0, > - .extent_order = EXTENT_ORDER, > - .domid = DOMID_SELF > - }; > > if (nr_pages > ARRAY_SIZE(frame_list)) > nr_pages = ARRAY_SIZE(frame_list); > @@ -486,9 +475,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages) > page = balloon_next_page(page); > } > > - set_xen_guest_handle(reservation.extent_start, frame_list); > - reservation.nr_extents = nr_pages; > - rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation); > + rc = xenmem_reservation_increase(nr_pages, frame_list); > if (rc <= 0) > return BP_EAGAIN; > > @@ -496,29 +483,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages) > page = balloon_retrieve(false); > BUG_ON(page == NULL); > > -#ifdef CONFIG_XEN_HAVE_PVMMU > - /* > - * We don't support PV MMU when Linux and Xen is using > - * different page granularity. > - */ > - BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE); > - > - if (!xen_feature(XENFEAT_auto_translated_physmap)) { > - unsigned long pfn = page_to_pfn(page); > - > - set_phys_to_machine(pfn, frame_list[i]); > - > - /* Link back into the page tables if not highmem. */ > - if (!PageHighMem(page)) { > - int ret; > - ret = HYPERVISOR_update_va_mapping( > - (unsigned long)__va(pfn << PAGE_SHIFT), > - mfn_pte(frame_list[i], PAGE_KERNEL), > - 0); > - BUG_ON(ret); > - } > - } > -#endif > + xenmem_reservation_va_mapping_update(1, &page, &frame_list[i]); > > /* Relinquish the page back to the allocator. */ > free_reserved_page(page); > @@ -535,11 +500,6 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) > unsigned long i; > struct page *page, *tmp; > int ret; > - struct xen_memory_reservation reservation = { > - .address_bits = 0, > - .extent_order = EXTENT_ORDER, > - .domid = DOMID_SELF > - }; > LIST_HEAD(pages); > > if (nr_pages > ARRAY_SIZE(frame_list)) > @@ -553,7 +513,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) > break; > } > adjust_managed_page_count(page, -1); > - scrub_page(page); > + xenmem_reservation_scrub_page(page); > list_add(&page->lru, &pages); > } > > @@ -575,25 +535,8 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) > /* XENMEM_decrease_reservation requires a GFN */ > frame_list[i++] = xen_page_to_gfn(page); > > -#ifdef CONFIG_XEN_HAVE_PVMMU > - /* > - * We don't support PV MMU when Linux and Xen is using > - * different page granularity. > - */ > - BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE); > - > - if (!xen_feature(XENFEAT_auto_translated_physmap)) { > - unsigned long pfn = page_to_pfn(page); > + xenmem_reservation_va_mapping_reset(1, &page); > > - if (!PageHighMem(page)) { > - ret = HYPERVISOR_update_va_mapping( > - (unsigned long)__va(pfn << PAGE_SHIFT), > - __pte_ma(0), 0); > - BUG_ON(ret); > - } > - __set_phys_to_machine(pfn, INVALID_P2M_ENTRY); > - } > -#endif > list_del(&page->lru); > > balloon_append(page); > @@ -601,9 +544,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) > > flush_tlb_all(); > > - set_xen_guest_handle(reservation.extent_start, frame_list); > - reservation.nr_extents = nr_pages; > - ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation); > + ret = xenmem_reservation_decrease(nr_pages, frame_list); > BUG_ON(ret != nr_pages); > > balloon_stats.current_pages -= nr_pages; > diff --git a/drivers/xen/mem-reservation.c b/drivers/xen/mem-reservation.c > new file mode 100644 > index 000000000000..29882e4324f5 > --- /dev/null > +++ b/drivers/xen/mem-reservation.c > @@ -0,0 +1,134 @@ > +// SPDX-License-Identifier: GPL-2.0 OR MIT > + > +/****************************************************************************** > + * Xen memory reservation utilities. > + * > + * Copyright (c) 2003, B Dragovic > + * Copyright (c) 2003-2004, M Williamson, K Fraser > + * Copyright (c) 2005 Dan M. Smith, IBM Corporation > + * Copyright (c) 2010 Daniel Kiper > + * Copyright (c) 2018, Oleksandr Andrushchenko, EPAM Systems Inc. > + */ > + > +#include > +#include > + > +#include > +#include > + > +#include > +#include > + > +/* > + * Use one extent per PAGE_SIZE to avoid to break down the page into > + * multiple frame. > + */ > +#define EXTENT_ORDER (fls(XEN_PFN_PER_PAGE) - 1) > + > +void xenmem_reservation_scrub_page(struct page *page) > +{ > +#ifdef CONFIG_XEN_SCRUB_PAGES > + clear_highpage(page); > +#endif > +} > +EXPORT_SYMBOL(xenmem_reservation_scrub_page); EXPORT_SYMBOL_GPL() Multiple times below, too. As a general rule of thumb: new exports should all be EXPORT_SYMBOL_GPL() if you can't give a reason why they shouldn't be. Juergen