Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761254AbZFOOqZ (ORCPT ); Mon, 15 Jun 2009 10:46:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751221AbZFOOqR (ORCPT ); Mon, 15 Jun 2009 10:46:17 -0400 Received: from casper.infradead.org ([85.118.1.10]:40289 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751173AbZFOOqR (ORCPT ); Mon, 15 Jun 2009 10:46:17 -0400 Subject: Re: [tip:perfcounters/core] x86: Add NMI types for kmap_atomic From: Peter Zijlstra To: linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, paulus@samba.org, acme@redhat.com, efault@gmx.de, npiggin@suse.de, tglx@linutronix.de, mingo@elte.hu Cc: linux-tip-commits@vger.kernel.org, "hugh.dickins" In-Reply-To: References: Content-Type: text/plain Date: Mon, 15 Jun 2009 16:46:05 +0200 Message-Id: <1245077165.6800.497.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4136 Lines: 119 On Mon, 2009-06-15 at 14:07 +0000, tip-bot for Peter Zijlstra wrote: > Commit-ID: 3ff0141aa3a03ca3388b40b36167d0a37919f3fd > Gitweb: http://git.kernel.org/tip/3ff0141aa3a03ca3388b40b36167d0a37919f3fd > Author: Peter Zijlstra > AuthorDate: Mon, 15 Jun 2009 12:40:41 +0200 > Committer: Ingo Molnar > CommitDate: Mon, 15 Jun 2009 15:57:52 +0200 > > x86: Add NMI types for kmap_atomic > > Two new kmap_atomic slots for NMI context. And teach pte_offset_map() > about NMI context. > > Signed-off-by: Peter Zijlstra > CC: Nick Piggin > Cc: Mike Galbraith > Cc: Paul Mackerras > Cc: Arnaldo Carvalho de Melo > Signed-off-by: Ingo Molnar > > > --- > arch/x86/include/asm/kmap_types.h | 4 +++- > arch/x86/include/asm/pgtable_32.h | 5 +++-- > 2 files changed, 6 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/include/asm/kmap_types.h b/arch/x86/include/asm/kmap_types.h > index 5759c16..ff00a44 100644 > --- a/arch/x86/include/asm/kmap_types.h > +++ b/arch/x86/include/asm/kmap_types.h > @@ -21,7 +21,9 @@ D(9) KM_IRQ0, > D(10) KM_IRQ1, > D(11) KM_SOFTIRQ0, > D(12) KM_SOFTIRQ1, > -D(13) KM_TYPE_NR > +D(13) KM_NMI, > +D(14) KM_NMI_PTE, > +D(15) KM_TYPE_NR > }; > > #undef D > diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h > index 31bd120..8546497 100644 > --- a/arch/x86/include/asm/pgtable_32.h > +++ b/arch/x86/include/asm/pgtable_32.h > @@ -49,13 +49,14 @@ extern void set_pmd_pfn(unsigned long, unsigned long, pgprot_t); > #endif > > #if defined(CONFIG_HIGHPTE) > +#define __KM_PTE (in_nmi() ? KM_NMI_PTE : KM_PTE0) > #define pte_offset_map(dir, address) \ > - ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE0) + \ > + ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), __KM_PTE) + \ > pte_index((address))) > #define pte_offset_map_nested(dir, address) \ > ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), KM_PTE1) + \ > pte_index((address))) > -#define pte_unmap(pte) kunmap_atomic((pte), KM_PTE0) > +#define pte_unmap(pte) kunmap_atomic((pte), __KM_PTE) > #define pte_unmap_nested(pte) kunmap_atomic((pte), KM_PTE1) > #else > #define pte_offset_map(dir, address) \ I just realized this has a kmap_atomic bug in... The below would fix it, but that's getting rather ugly :-/, alternatively I would have to introduce something like pte_offset_map_irq() which would make the irq/nmi detection and leave the regular code paths alone, however that would mean either duplicating the gup_fast() pagewalk or passing down a pte function pointer, which would only duplicate the gup_pte_range() bit, neither is really attractive... Index: linux-2.6/arch/x86/include/asm/kmap_types.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/kmap_types.h +++ linux-2.6/arch/x86/include/asm/kmap_types.h @@ -19,11 +19,12 @@ D(7) KM_PTE0, D(8) KM_PTE1, D(9) KM_IRQ0, D(10) KM_IRQ1, -D(11) KM_SOFTIRQ0, -D(12) KM_SOFTIRQ1, -D(13) KM_NMI, -D(14) KM_NMI_PTE, -D(15) KM_TYPE_NR +D(11) KM_IRQ_PTE, +D(12) KM_SOFTIRQ0, +D(13) KM_SOFTIRQ1, +D(14) KM_NMI, +D(15) KM_NMI_PTE, +D(16) KM_TYPE_NR }; #undef D Index: linux-2.6/arch/x86/include/asm/pgtable_32.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/pgtable_32.h +++ linux-2.6/arch/x86/include/asm/pgtable_32.h @@ -49,7 +49,10 @@ extern void set_pmd_pfn(unsigned long, u #endif #if defined(CONFIG_HIGHPTE) -#define __KM_PTE (in_nmi() ? KM_NMI_PTE : KM_PTE0) +#define __KM_PTE \ + (in_nmi() ? KM_NMI_PTE : \ + in_irq() ? KM_IRQ_PTE : \ + KM_PTE0) #define pte_offset_map(dir, address) \ ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)), __KM_PTE) + \ pte_index((address))) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/