Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751463AbaKYU71 (ORCPT ); Tue, 25 Nov 2014 15:59:27 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:56792 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751111AbaKYU7Y (ORCPT ); Tue, 25 Nov 2014 15:59:24 -0500 From: "Rafael J. Wysocki" To: Hanjun Guo Cc: Hanjun Guo , Catalin Marinas , Mark Rutland , Olof Johansson , Grant Likely , Will Deacon , Graeme Gregory , Arnd Bergmann , Sudeep Holla , Jon Masters , Jason Cooper , Marc Zyngier , Bjorn Helgaas , Daniel Lezcano , Mark Brown , Rob Herring , Robert Richter , Lv Zheng , Robert Moore , Lorenzo Pieralisi , Liviu Dudau , Randy Dunlap , Charles.Garcia-Tobin@arm.com, Kangkang.Shen@huawei.com, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org, Ashwin Chaugule , Tomasz Nowicki Subject: Re: [PATCH v5 02/18] ACPI / table: Add new function to get table entries Date: Tue, 25 Nov 2014 22:20:39 +0100 Message-ID: <1591450.lUZUanAOs6@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <5473F99D.6090505@huawei.com> References: <1413553034-20956-1-git-send-email-hanjun.guo@linaro.org> <1581499.U8906vqSiO@vostro.rjw.lan> <5473F99D.6090505@huawei.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 On Tuesday, November 25, 2014 11:38:05 AM Hanjun Guo wrote: > On 2014/11/24 22:51, Rafael J. Wysocki wrote: > > On Monday, November 24, 2014 07:03:54 PM Hanjun Guo wrote: > >> On 2014-11-24 9:27, Rafael J. Wysocki wrote: > >>> On Friday, October 17, 2014 09:36:58 PM Hanjun Guo wrote: > >>>> From: Ashwin Chaugule > >>>> > >>>> The acpi_table_parse() function has a callback that > >>>> passes a pointer to a table_header. Add a new function > >>>> which takes this pointer and parses its entries. This > >>>> eliminates the need to re-traverse all the tables for > >>>> each call. e.g. as in acpi_table_parse_madt() which is > >>>> normally called after acpi_table_parse(). > >>>> > >>>> Acked-by: Grant Likely > >>>> Signed-off-by: Ashwin Chaugule > >>>> Signed-off-by: Tomasz Nowicki > >>>> Signed-off-by: Hanjun Guo > >>>> --- > >>>> drivers/acpi/tables.c | 67 ++++++++++++++++++++++++++++++++++--------------- > >>>> include/linux/acpi.h | 4 +++ > >>>> 2 files changed, 51 insertions(+), 20 deletions(-) > >>>> > >>>> diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c > >>>> index 6d5a6cd..21ae521 100644 > >>>> --- a/drivers/acpi/tables.c > >>>> +++ b/drivers/acpi/tables.c > >>>> @@ -192,17 +192,14 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header) > >>>> > >>>> > >>>> int __init > >>>> -acpi_table_parse_entries(char *id, > >>>> - unsigned long table_size, > >>>> - int entry_id, > >>>> - acpi_tbl_entry_handler handler, > >>>> - unsigned int max_entries) > >>>> +acpi_parse_entries(unsigned long table_size, > >>>> + acpi_tbl_entry_handler handler, > >>>> + struct acpi_table_header *table_header, > >>>> + int entry_id, unsigned int max_entries) > >>>> { > >>>> - struct acpi_table_header *table_header = NULL; > >>>> struct acpi_subtable_header *entry; > >>>> - unsigned int count = 0; > >>>> + int count = 0; > >>>> unsigned long table_end; > >>>> - acpi_size tbl_size; > >>>> > >>>> if (acpi_disabled) > >>>> return -ENODEV; > >>>> @@ -210,13 +207,11 @@ acpi_table_parse_entries(char *id, > >>>> if (!handler) > >>>> return -EINVAL; > >>>> > >>>> - if (strncmp(id, ACPI_SIG_MADT, 4) == 0) > >>>> - acpi_get_table_with_size(id, acpi_apic_instance, &table_header, &tbl_size); > >>>> - else > >>>> - acpi_get_table_with_size(id, 0, &table_header, &tbl_size); > >>>> + if (!table_size) > >>>> + return -EINVAL; > >>>> > >>>> if (!table_header) { > >>>> - pr_warn("%4.4s not present\n", id); > >>>> + pr_warn("Table header not present\n"); > >>> The message doesn't make sense any more if the table signature is not printed. > > For this message, since no table id is passed, and this message is printed in > acpi_table_parse_entries() before this function is called, I think we can check > the table_header before call this function and remove the printed message here. table_header needs to be checked against NULL in the caller and the message printed from there to my eyes. > >>> > >>>> return -ENODEV; > >>>> } > >>>> > >>>> @@ -232,30 +227,62 @@ acpi_table_parse_entries(char *id, > >>>> if (entry->type == entry_id > >>>> && (!max_entries || count++ < max_entries)) > >>>> if (handler(entry, table_end)) > >>>> - goto err; > >>>> + return -EINVAL; > >>>> > >>>> /* > >>>> * If entry->length is 0, break from this loop to avoid > >>>> * infinite loop. > >>>> */ > >>>> if (entry->length == 0) { > >>>> - pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, entry_id); > >>>> - goto err; > >>>> + pr_err("[0x%02x] Invalid zero length\n", entry_id); > > For this one, since the table_header is valid now, we can keep it with: Fine by me. > - pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, entry_id); > + pr_err("[%4.4s:0x%02x] Invalid zero length\n", table_header->signature, entry_id); > > >>> Same here. > >> How about remove the message and return directly? > > We could do that, but for what reason? Is the message not useful? > > I agree with you, the message is useful I think, how about the comments above? Please see above. -- 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/