Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752262Ab3HBMuI (ORCPT ); Fri, 2 Aug 2013 08:50:08 -0400 Received: from hydra.sisk.pl ([212.160.235.94]:52035 "EHLO hydra.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751570Ab3HBMuF (ORCPT ); Fri, 2 Aug 2013 08:50:05 -0400 From: "Rafael J. Wysocki" To: Tang Chen Cc: robert.moore@intel.com, lv.zheng@intel.com, lenb@kernel.org, tglx@linutronix.de, mingo@elte.hu, hpa@zytor.com, akpm@linux-foundation.org, tj@kernel.org, trenn@suse.de, yinghai@kernel.org, jiang.liu@huawei.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, mgorman@suse.de, minchan@kernel.org, mina86@mina86.com, gong.chen@linux.intel.com, vasilis.liaskovitis@profitbricks.com, lwoodman@redhat.com, riel@redhat.com, jweiner@redhat.com, prarit@redhat.com, zhangyanfei@cn.fujitsu.com, yanghy@cn.fujitsu.com, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH v2 RESEND 05/18] x86, ACPICA: Split acpi_boot_table_init() into two parts. Date: Fri, 02 Aug 2013 15:00:06 +0200 Message-ID: <7364455.HW1C4G1skW@vostro.rjw.lan> User-Agent: KMail/4.9.5 (Linux/3.10.0+; KDE/4.9.5; x86_64; ; ) In-Reply-To: <1375434877-20704-6-git-send-email-tangchen@cn.fujitsu.com> References: <1375434877-20704-1-git-send-email-tangchen@cn.fujitsu.com> <1375434877-20704-6-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4976 Lines: 137 On Friday, August 02, 2013 05:14:24 PM Tang Chen wrote: > In ACPI, SRAT(System Resource Affinity Table) contains NUMA info. > The memory affinities in SRAT record every memory range in the > system, and also, flags specifying if the memory range is > hotpluggable. > (Please refer to ACPI spec 5.0 5.2.16) > > memblock starts to work at very early time, and SRAT has not been > parsed. So we don't know which memory is hotpluggable. In order > to use memblock to reserve hotpluggable memory, we need to obtain > SRAT memory affinity info earlier. > > In the current acpi_boot_table_init(), it does the following: > 1. Parse RSDT, so that we can find all the tables. > 2. Initialize acpi_gbl_root_table_list, an array of acpi table > descriptors used to store each table's address, length, signature, > and so on. > 3. Check if there is any table in initrd intending to override > tables from firmware. If so, override the firmware tables. > 4. Initialize all the data in acpi_gbl_root_table_list. > > In order to parse SRAT at early time, we need to do similar job as > step 1 and 2 above earlier to obtain SRAT. It will be very convenient > if we have acpi_gbl_root_table_list initialized. We can use address > and signature to find SRAT. > > Since step 1 and 2 allocates no memory, it is OK to do these two > steps earlier. > > But step 3 will check acpi initrd table override, not just SRAT, > but also all the other tables. So it is better to keep it untouched. > > This patch splits acpi_boot_table_init() into two steps: > 1. Parse RSDT, which cannot be overrided, and initialize > acpi_gbl_root_table_list. (step 1 + 2 above) > 2. Install all ACPI tables into acpi_gbl_root_table_list. > (step 3 + 4 above) > > In later patches, we will do step 1 + 2 earlier. Please note that Linux is not the only user of the code you're modifying, so you need to make it possible to use the existing functions. In particular, acpi_tb_parse_root_table() can't be modified the way you did it, because that would require all of the users of ACPICA to be modified. > Signed-off-by: Tang Chen > Reviewed-by: Zhang Yanfei > --- > drivers/acpi/acpica/tbutils.c | 25 ++++++++++++++++++++++--- > drivers/acpi/tables.c | 2 ++ > include/acpi/acpixf.h | 2 ++ > 3 files changed, 26 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c > index bffdfc7..e3621cf 100644 > --- a/drivers/acpi/acpica/tbutils.c > +++ b/drivers/acpi/acpica/tbutils.c > @@ -577,9 +577,30 @@ acpi_tb_parse_root_table(acpi_physical_address rsdp_address) > */ > acpi_os_unmap_memory(table, length); > > + return_ACPI_STATUS(AE_OK); > +} > + > +/******************************************************************************* > + * > + * FUNCTION: acpi_tb_install_root_table > + * > + * DESCRIPTION: This function installs all the ACPI tables in RSDT into > + * acpi_gbl_root_table_list. > + * > + ******************************************************************************/ > + > +void __init > +acpi_tb_install_root_table() > +{ > + int i; > + > /* > * Complete the initialization of the root table array by examining > - * the header of each table > + * the header of each table. > + * > + * First two entries in the table array are reserved for the DSDT > + * and FACS, which are not actually present in the RSDT/XSDT - they > + * come from the FADT. > */ > for (i = 2; i < acpi_gbl_root_table_list.current_table_count; i++) { > acpi_tb_install_table(acpi_gbl_root_table_list.tables[i]. > @@ -593,6 +614,4 @@ acpi_tb_parse_root_table(acpi_physical_address rsdp_address) > acpi_tb_parse_fadt(i); > } > } > - > - return_ACPI_STATUS(AE_OK); > } > diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c > index d67a1fe..8860e79 100644 > --- a/drivers/acpi/tables.c > +++ b/drivers/acpi/tables.c > @@ -353,6 +353,8 @@ int __init acpi_table_init(void) > if (ACPI_FAILURE(status)) > return 1; > > + acpi_tb_install_root_table(); > + > check_multiple_madt(); > return 0; > } > diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h > index 22d497e..e9c9b88 100644 > --- a/include/acpi/acpixf.h > +++ b/include/acpi/acpixf.h > @@ -118,6 +118,8 @@ acpi_status > acpi_initialize_tables(struct acpi_table_desc *initial_storage, > u32 initial_table_count, u8 allow_resize); > > +void acpi_tb_install_root_table(void); > + > acpi_status __init acpi_initialize_subsystem(void); > > acpi_status acpi_enable_subsystem(u32 flags); > Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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/