Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753327Ab0L1DVF (ORCPT ); Mon, 27 Dec 2010 22:21:05 -0500 Received: from mga02.intel.com ([134.134.136.20]:60954 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753246Ab0L1DVE (ORCPT ); Mon, 27 Dec 2010 22:21:04 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.60,237,1291622400"; d="scan'208";a="691226865" Subject: Re: [PATCH] ACPI: use ioremap_cache() From: Shaohua Li To: Len Brown Cc: Jack Steiner , "hpa@zytor.com" , Henrique de Moraes Holschuh , "tony.luck@gmail.com" , "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "gbeshers@sgi.com" In-Reply-To: References: <20101214220932.GA1206@sgi.com> <20101215024136.GB19601@sgi.com> <20101215164635.GA27373@sgi.com> Content-Type: text/plain; charset="UTF-8" Date: Tue, 28 Dec 2010 11:21:00 +0800 Message-ID: <1293506460.10593.43.camel@sli10-conroe> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3783 Lines: 112 On Fri, 2010-12-17 at 16:08 +0800, Len Brown wrote: > From: Len Brown > > Although the temporary boot-time ACPI table mappings > were set up with CPU caching enabled, the permanent table > mappings and AML run-time region memory accesses were > set up with ioremap(), which on x86 is a synonym for > ioremap_nocache(). > > Changing this to ioremap_cache() improves performance as > seen when accessing the tables via acpidump, > or /sys/firmware/acpi/tables. It should also improve > AML run-time performance. > > No change on ia64. > > Reported-by: Jack Steiner > Signed-off-by: Len Brown > --- > arch/ia64/include/asm/io.h | 5 +++++ > drivers/acpi/osl.c | 6 +++--- > 2 files changed, 8 insertions(+), 3 deletions(-) > > diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h > index cc8335e..009a7e0 100644 > --- a/arch/ia64/include/asm/io.h > +++ b/arch/ia64/include/asm/io.h > @@ -426,6 +426,11 @@ extern void __iomem * ioremap_nocache (unsigned long offset, unsigned long size) > extern void iounmap (volatile void __iomem *addr); > extern void __iomem * early_ioremap (unsigned long phys_addr, unsigned long size); > extern void early_iounmap (volatile void __iomem *addr, unsigned long size); > +static inline void __iomem * ioremap_cache (unsigned long phys_addr, unsigned long size) > +{ > + return ioremap(unsigned long phys_addr, unsigned long size); > +} > + > > /* > * String version of IO memory access ops: > diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c > index 966fedd..85eba53 100644 > --- a/drivers/acpi/osl.c > +++ b/drivers/acpi/osl.c > @@ -324,7 +324,7 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) > > pg_off = round_down(phys, PAGE_SIZE); > pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; > - virt = ioremap(pg_off, pg_sz); > + virt = ioremap_cache(pg_off, pg_sz); > if (!virt) { > kfree(map); > return NULL; > @@ -646,7 +646,7 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width) > virt_addr = acpi_map_vaddr_lookup(phys_addr, size); > rcu_read_unlock(); > if (!virt_addr) { > - virt_addr = ioremap(phys_addr, size); > + virt_addr = ioremap_cache(phys_addr, size); > unmap = 1; > } > if (!value) > @@ -682,7 +682,7 @@ acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width) > virt_addr = acpi_map_vaddr_lookup(phys_addr, size); > rcu_read_unlock(); > if (!virt_addr) { > - virt_addr = ioremap(phys_addr, size); > + virt_addr = ioremap_cache(phys_addr, size); > unmap = 1; > } blindly map the range as cache is not ok. for example: OperationRegion (RCRB, SystemMemory, 0xFED1C000, 0x4000) Field (RCRB, DWordAcc, Lock, Preserve) { Offset (0x1000), Offset (0x3000), Offset (0x3404), HPAS, 2, , 5, HPAE, 1, Offset (0x3418), , 1, PATD, 1, SATD, 1, SMBD, 1, HDAD, 1, A97D, 1, Offset (0x341A), RP1D, 1, RP2D, 1, RP3D, 1, RP4D, 1, RP5D, 1, RP6D, 1 } RCRB is a memory mapped io. In ICH, it's chipset configuration registers. this range can't be cached. I thought we should add a check like if page is E820_RAM or E820_ACPI then cached_map else uncached_map we have page_is_ram() API which just checks E820_RAM, I thought we can add a new API to check E820_ACPI. Thanks, Shaohua -- 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/