From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f41.google.com (mail-wm0-f41.google.com [74.125.82.41]) by kanga.kvack.org (Postfix) with ESMTP id 8A3636B0005 for ; Wed, 27 Jan 2016 05:09:43 -0500 (EST) Received: by mail-wm0-f41.google.com with SMTP id n5so20113664wmn.1 for ; Wed, 27 Jan 2016 02:09:43 -0800 (PST) Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com. [195.75.94.106]) by mx.google.com with ESMTPS id q10si7512729wjo.159.2016.01.27.02.09.42 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 27 Jan 2016 02:09:42 -0800 (PST) Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 27 Jan 2016 10:09:41 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 0B8421B08077 for ; Wed, 27 Jan 2016 10:09:47 +0000 (GMT) Received: from d06av07.portsmouth.uk.ibm.com (d06av07.portsmouth.uk.ibm.com [9.149.37.248]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u0RA9d157274998 for ; Wed, 27 Jan 2016 10:09:39 GMT Received: from d06av07.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av07.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u0RA9csr026602 for ; Wed, 27 Jan 2016 05:09:39 -0500 From: Christian Borntraeger Subject: [PATCH v3 2/3] x86: query dynamic DEBUG_PAGEALLOC setting Date: Wed, 27 Jan 2016 11:10:00 +0100 Message-Id: <1453889401-43496-3-git-send-email-borntraeger@de.ibm.com> In-Reply-To: <1453889401-43496-1-git-send-email-borntraeger@de.ibm.com> References: <1453889401-43496-1-git-send-email-borntraeger@de.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, davem@davemloft.net, Joonsoo Kim , davej@codemonkey.org.uk, Christian Borntraeger We can use debug_pagealloc_enabled() to check if we can map the identity mapping with 2MB pages. We can also add the state into the dump_stack output. The patch does not touch the code for the 1GB pages, which ignored CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well? Signed-off-by: Christian Borntraeger Reviewed-by: Thomas Gleixner --- arch/x86/kernel/dumpstack.c | 5 ++--- arch/x86/mm/init.c | 7 ++++--- arch/x86/mm/pageattr.c | 14 ++++---------- 3 files changed, 10 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 9c30acf..32e5699 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -265,9 +265,8 @@ int __die(const char *str, struct pt_regs *regs, long err) #ifdef CONFIG_SMP printk("SMP "); #endif -#ifdef CONFIG_DEBUG_PAGEALLOC - printk("DEBUG_PAGEALLOC "); -#endif + if (debug_pagealloc_enabled()) + printk("DEBUG_PAGEALLOC "); #ifdef CONFIG_KASAN printk("KASAN"); #endif diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 493f541..39823fd 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -150,13 +150,14 @@ static int page_size_mask; static void __init probe_page_size_mask(void) { -#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK) +#if !defined(CONFIG_KMEMCHECK) /* - * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. + * For CONFIG_KMEMCHECK or pagealloc debugging, identity mapping will + * use small pages. * This will simplify cpa(), which otherwise needs to support splitting * large pages into small in interrupt context, etc. */ - if (cpu_has_pse) + if (cpu_has_pse && !debug_pagealloc_enabled()) page_size_mask |= 1 << PG_LEVEL_2M; #endif diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index fc6a4c8..5f68987 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -106,12 +106,6 @@ static inline unsigned long highmap_end_pfn(void) #endif -#ifdef CONFIG_DEBUG_PAGEALLOC -# define debug_pagealloc 1 -#else -# define debug_pagealloc 0 -#endif - static inline int within(unsigned long addr, unsigned long start, unsigned long end) { @@ -708,10 +702,10 @@ static int split_large_page(struct cpa_data *cpa, pte_t *kpte, { struct page *base; - if (!debug_pagealloc) + if (!debug_pagealloc_enabled()) spin_unlock(&cpa_lock); base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); - if (!debug_pagealloc) + if (!debug_pagealloc_enabled()) spin_lock(&cpa_lock); if (!base) return -ENOMEM; @@ -1331,10 +1325,10 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY)) cpa->numpages = 1; - if (!debug_pagealloc) + if (!debug_pagealloc_enabled()) spin_lock(&cpa_lock); ret = __change_page_attr(cpa, checkalias); - if (!debug_pagealloc) + if (!debug_pagealloc_enabled()) spin_unlock(&cpa_lock); if (ret) return ret; -- 2.3.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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