Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264258AbUARXHA (ORCPT ); Sun, 18 Jan 2004 18:07:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264261AbUARXHA (ORCPT ); Sun, 18 Jan 2004 18:07:00 -0500 Received: from colin2.muc.de ([193.149.48.15]:53261 "HELO colin2.muc.de") by vger.kernel.org with SMTP id S264258AbUARXG5 (ORCPT ); Sun, 18 Jan 2004 18:06:57 -0500 Date: 19 Jan 2004 00:07:43 +0100 Date: Mon, 19 Jan 2004 00:07:43 +0100 From: Andi Kleen To: Linus Torvalds , Andi Kleen , Andrew Morton , jh@suse.cz, Kernel Mailing List Subject: Re: [PATCH] Add noinline attribute - new extable sort patch Message-ID: <20040118230743.GA12989@colin2.muc.de> References: <20040114083114.GA1784@averell> <20040115074834.GA38796@colin2.muc.de> <20040116101345.GA96037@colin2.muc.de> <20040118204700.GA31601@twiddle.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040118204700.GA31601@twiddle.net> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2974 Lines: 93 On Sun, Jan 18, 2004 at 12:47:00PM -0800, Richard Henderson wrote: > On Fri, Jan 16, 2004 at 11:13:45AM +0100, Andi Kleen wrote: > > Ok, here is a new patch that does the whole thing in generic code and for > > modules too. I didn't bother to change the sort algorithm because the > > existing one works well enough. > > One, you've still got the function marked __init. > > Two, the format of struct exception_table_entry is arch specific. > That comparison won't work on Alpha, because "insn" is encoded > pc-relative. I looked at it more closely now. Alpha (and IA64 which uses the same format) would be relatively easy to do. But sparc and sparc64 have a very strange different format which would be too complicated to handle. I withdraw the patch that does the sort in init/main.c. Instead just let's do it in arch/i386 like in the original patch Also it doesn't do it for modules because there are no __init sections there (avoids some ifdefs) Andrew, please replace the previous patch with that one. Thanks, -Andi diff -u linux-34/arch/i386/mm/extable.c-o linux-34/arch/i386/mm/extable.c --- linux-34/arch/i386/mm/extable.c-o 2003-05-27 03:01:00.000000000 +0200 +++ linux-34/arch/i386/mm/extable.c 2004-01-15 08:39:31.657013864 +0100 @@ -5,6 +5,7 @@ #include #include #include +#include #include /* Simple binary search */ @@ -56,3 +57,28 @@ return 0; } + +/* When an exception handler is in an non standard section (like __init) + the fixup table can end up unordered. Fix that here. */ +__init int check_extable(void) +{ + extern struct exception_table_entry __start___ex_table[]; + extern struct exception_table_entry __stop___ex_table[]; + struct exception_table_entry *e; + int change; + + /* The input is near completely presorted, which makes bubble sort the + best (and simplest) sort algorithm. */ + do { + change = 0; + for (e = __start___ex_table+1; e < __stop___ex_table; e++) { + if (e->insn < e[-1].insn) { + struct exception_table_entry tmp = e[-1]; + e[-1] = e[0]; + e[0] = tmp; + change = 1; + } + } + } while (change != 0); + return 0; +} diff -u linux-34/arch/i386/kernel/setup.c-o linux-34/arch/i386/kernel/setup.c --- linux-34/arch/i386/kernel/setup.c-o 2004-01-09 09:27:09.000000000 +0100 +++ linux-34/arch/i386/kernel/setup.c 2004-01-15 08:39:30.438199152 +0100 @@ -119,6 +119,7 @@ extern void generic_apic_probe(char *); extern int root_mountflags; extern char _end[]; +extern int check_extable(void); unsigned long saved_videomode; @@ -1114,6 +1115,8 @@ #endif paging_init(); + check_extable(); + dmi_scan_machine(); #ifdef CONFIG_X86_GENERICARCH - 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/