linux-kernel - Re: [PATCH 12/14] x86_64 irq: Add constants for the reserved IRQ vectors.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <m1wt26pjxp.fsf@ebiederm.dsl.xmission.com>
Date:	Sun, 25 Feb 2007 04:15:30 -0700
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	Pavel Machek <pavel@....cz>
Cc:	Andrew Morton <akpm@...l.org>, linux-kernel@...r.kernel.org,
	Zwane Mwaikambo <zwane@...radead.org>,
	Ashok Raj <ashok.raj@...el.com>, Ingo Molnar <mingo@...e.hu>,
	"Lu, Yinghai" <yinghai.lu@....com>,
	Natalie Protasevich <protasnb@...il.com>,
	Andi Kleen <ak@...e.de>,
	"Siddha, Suresh B" <suresh.b.siddha@...el.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH 12/14] x86_64 irq: Add constants for the reserved IRQ vectors.

Pavel Machek <pavel@....cz> writes:

> Hi!
>
>> For the ISA irqs we reserve 16 vectors.  This patch adds constants for
>> those vectors and modifies the code to use them.  Making the code a
>> little clearer and making it possible to move these vectors in the future.
>
>
>>  /*
>>   * Vectors 0x20-0x2f are used for ISA interrupts.
>>   */
>> +#define IRQ0_VECTOR		FIRST_EXTERNAL_VECTOR
>> +#define IRQ1_VECTOR		IRQ0_VECTOR + 1
>
> Maybe IRQ_VECTOR(1) would be similary readable, and would avoid 
>
>> +#define IRQ2_VECTOR		IRQ0_VECTOR + 2
>> +#define IRQ3_VECTOR		IRQ0_VECTOR + 3
>> +#define IRQ4_VECTOR		IRQ0_VECTOR + 4
>> +#define IRQ5_VECTOR		IRQ0_VECTOR + 5 
>> +#define IRQ6_VECTOR		IRQ0_VECTOR + 6
>> +#define IRQ7_VECTOR		IRQ0_VECTOR + 7
>> +#define IRQ8_VECTOR		IRQ0_VECTOR + 8
>> +#define IRQ9_VECTOR		IRQ0_VECTOR + 9
>> +#define IRQ10_VECTOR		IRQ0_VECTOR + 10
>> +#define IRQ11_VECTOR		IRQ0_VECTOR + 11
>> +#define IRQ12_VECTOR		IRQ0_VECTOR + 12
>> +#define IRQ13_VECTOR		IRQ0_VECTOR + 13
>> +#define IRQ14_VECTOR		IRQ0_VECTOR + 14
>> +#define IRQ15_VECTOR		IRQ0_VECTOR + 15
>
> ...these defines?

It would, and mostly I like it.  However, of the 1500+ possible irqs
exactly 16 have a reserved vector.  IRQ_VECTOR(N) does not convey
that in fact it conveys the opposite impression.

So I think the code is more maintainable with the distinct
definitions.

Eric
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/