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 E438CC43334 for ; Mon, 20 Jun 2022 11:07:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239899AbiFTLH0 (ORCPT ); Mon, 20 Jun 2022 07:07:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241235AbiFTLHY (ORCPT ); Mon, 20 Jun 2022 07:07:24 -0400 Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E349D15803 for ; Mon, 20 Jun 2022 04:07:22 -0700 (PDT) Received: by mail-pl1-x632.google.com with SMTP id p2so37879pls.4 for ; Mon, 20 Jun 2022 04:07:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=mM7s3v4b97sYa4DNCsb4b4pY8OOrPntnEzMKTxkrZCM=; b=gIu6W0ZIr/zYXLZR0jiYfFo6E18oWdKoXjARFWXS+zZf7fY/UQtXQsa0q11G5ojxlh QPaT79UFh/2Be873OwRYKLBoDMkwtiApXCRGrvc9Qu1E40kH4y9DOZ1Wlkt3mbSVY4f4 AJZeBzIYxFP2CPQ3ucPs8G377XblLDiz1tZ2bV9v2/CMkAcEY7wGx5AN82RVvaoz18nZ mv9nljhR8AXVEmfjx2gbRaPS3SF3IoVSwH3UwVA0lPUBiiiP8kjxlkY5iFcPdlv8Pf9h I0oGIkmib6iaVtMoK9CVeiRgrZnLV2u5xwvz72yAlNeUQAdANv09B3o3ZkNysai1sQxM Bmhg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=mM7s3v4b97sYa4DNCsb4b4pY8OOrPntnEzMKTxkrZCM=; b=Q6KlfPDeQetx9u6xfkaV6Uksrm4bg+veXuEdWzCogKBTyb196U3DeF4XMs90Xh3/o2 ZewAmY5Dzby+FhKMW8x9ORQ4c2BL/NiV+z4dsiApPmHyGZb9bH3mwEjFgnzO/4FNPC75 JC3CzkX+W5ec010Canbp0yv98zJGk01Z8chvvBGGrosvkE4Vj42mvMPzZtFB3CEMHwRu xdRru/m1P5lovThZWsO7VnqozMfz66WSZHN1tErveJh1uukEuqjwC8fOqHyDWWaeFKZ2 d/JqFhCFINkNZ7SdmGlcQHOfAjdj/GLcTK1gy2JfT09YWeI/aCQtIqd1HPGGOtXRRkFZ uviw== X-Gm-Message-State: AJIora/e+zAAJB+9yX7uRjYWcoQ4ftuS7cjFds5B9PKEBS87Tu6aZxO7 jvjam5rOLlKRl7AT+bE8Eq2Opg== X-Google-Smtp-Source: AGRyM1uFiRFO3G72OlGQJs4sGnpULsAK3KSRtJN9Fgt8rFs5zX6qpNiEZwdJU5OUBW4nsQpQGLcK2A== X-Received: by 2002:a17:902:7042:b0:16a:2156:c325 with SMTP id h2-20020a170902704200b0016a2156c325mr5882728plt.166.1655723242390; Mon, 20 Jun 2022 04:07:22 -0700 (PDT) Received: from FVFYT0MHHV2J.bytedance.net ([139.177.225.255]) by smtp.gmail.com with ESMTPSA id iw10-20020a170903044a00b0016a214e4afasm2385962plb.125.2022.06.20.04.07.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Jun 2022 04:07:22 -0700 (PDT) From: Muchun Song To: akpm@linux-foundation.org, corbet@lwn.net, david@redhat.com, mike.kravetz@oracle.com, osalvador@suse.de, paulmck@kernel.org Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, smuchun@gmail.com, Muchun Song Subject: [PATCH v5 1/2] mm: memory_hotplug: enumerate all supported section flags Date: Mon, 20 Jun 2022 19:06:15 +0800 Message-Id: <20220620110616.12056-2-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.1 (Apple Git-133) In-Reply-To: <20220620110616.12056-1-songmuchun@bytedance.com> References: <20220620110616.12056-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org We are almost running out of section flags, only one bit is available in the worst case (powerpc with 256k pages). However, there are still some free bits (in ->section_mem_map) on other architectures (e.g. x86_64 has 10 bits available, arm64 has 8 bits available with worst case of 64K pages). We have hard coded those numbers in code, it is inconvenient to use those bits on other architectures except powerpc. So transfer those section flags to enumeration to make it easy to add new section flags in the future. Also, move SECTION_TAINT_ZONE_DEVICE into the scope of CONFIG_ZONE_DEVICE to save a bit on non-zone-device case. Signed-off-by: Muchun Song --- include/linux/mmzone.h | 41 ++++++++++++++++++++++++++++++++--------- mm/memory_hotplug.c | 6 ++++++ mm/sparse.c | 2 +- 3 files changed, 39 insertions(+), 10 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index aab70355d64f..2b5757752333 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1418,16 +1418,32 @@ extern size_t mem_section_usage_size(void); * (equal SECTION_SIZE_BITS - PAGE_SHIFT), and the * worst combination is powerpc with 256k pages, * which results in PFN_SECTION_SHIFT equal 6. - * To sum it up, at least 6 bits are available. + * To sum it up, at least 6 bits are available on all architectures. + * However, we can exceed 6 bits on some other architectures except + * powerpc (e.g. 15 bits are available on x86_64, 13 bits are available + * with the worst case of 64K pages on arm64) if we make sure the + * exceeded bit is not applicable to powerpc. */ -#define SECTION_MARKED_PRESENT (1UL<<0) -#define SECTION_HAS_MEM_MAP (1UL<<1) -#define SECTION_IS_ONLINE (1UL<<2) -#define SECTION_IS_EARLY (1UL<<3) -#define SECTION_TAINT_ZONE_DEVICE (1UL<<4) -#define SECTION_MAP_LAST_BIT (1UL<<5) -#define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1)) -#define SECTION_NID_SHIFT 6 +enum { + SECTION_MARKED_PRESENT_BIT, + SECTION_HAS_MEM_MAP_BIT, + SECTION_IS_ONLINE_BIT, + SECTION_IS_EARLY_BIT, +#ifdef CONFIG_ZONE_DEVICE + SECTION_TAINT_ZONE_DEVICE_BIT, +#endif + SECTION_MAP_LAST_BIT, +}; + +#define SECTION_MARKED_PRESENT BIT(SECTION_MARKED_PRESENT_BIT) +#define SECTION_HAS_MEM_MAP BIT(SECTION_HAS_MEM_MAP_BIT) +#define SECTION_IS_ONLINE BIT(SECTION_IS_ONLINE_BIT) +#define SECTION_IS_EARLY BIT(SECTION_IS_EARLY_BIT) +#ifdef CONFIG_ZONE_DEVICE +#define SECTION_TAINT_ZONE_DEVICE BIT(SECTION_TAINT_ZONE_DEVICE_BIT) +#endif +#define SECTION_MAP_MASK (~(BIT(SECTION_MAP_LAST_BIT) - 1)) +#define SECTION_NID_SHIFT SECTION_MAP_LAST_BIT static inline struct page *__section_mem_map_addr(struct mem_section *section) { @@ -1466,12 +1482,19 @@ static inline int online_section(struct mem_section *section) return (section && (section->section_mem_map & SECTION_IS_ONLINE)); } +#ifdef CONFIG_ZONE_DEVICE static inline int online_device_section(struct mem_section *section) { unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE; return section && ((section->section_mem_map & flags) == flags); } +#else +static inline int online_device_section(struct mem_section *section) +{ + return 0; +} +#endif static inline int online_section_nr(unsigned long nr) { diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 1f1a730c4499..6662b86e9e64 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -670,12 +670,18 @@ static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned lon } +#ifdef CONFIG_ZONE_DEVICE static void section_taint_zone_device(unsigned long pfn) { struct mem_section *ms = __pfn_to_section(pfn); ms->section_mem_map |= SECTION_TAINT_ZONE_DEVICE; } +#else +static inline void section_taint_zone_device(unsigned long pfn) +{ +} +#endif /* * Associate the pfn range with the given zone, initializing the memmaps diff --git a/mm/sparse.c b/mm/sparse.c index cb3bfae64036..e5a8a3a0edd7 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -281,7 +281,7 @@ static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long p { unsigned long coded_mem_map = (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); - BUILD_BUG_ON(SECTION_MAP_LAST_BIT > (1UL< PFN_SECTION_SHIFT); BUG_ON(coded_mem_map & ~SECTION_MAP_MASK); return coded_mem_map; } -- 2.11.0