From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758156Ab0IUSa6 (ORCPT ); Tue, 21 Sep 2010 14:30:58 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:51407 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754157Ab0IUSa5 (ORCPT >); Tue, 21 Sep 2010 14:30:57 -0400 Date: Tue, 21 Sep 2010 14:30:03 -0400 From: Konrad Rzeszutek Wilk To: Jason Baron Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, mathieu.desnoyers@polymtl.ca, hpa@zytor.com, tglx@linutronix.de, rostedt@goodmis.org, andi@firstfloor.org, roland@redhat.com, rth@redhat.com, mhiramat@redhat.com, fweisbec@gmail.com, avi@redhat.com, davem@davemloft.net, vgoyal@redhat.com, sam@ravnborg.org, tony@bakeyournoodle.com Subject: Re: [PATCH 08/10] jump label v11: x86 support Message-ID: <20100921183003.GB22088@dumpdata.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 17, 2010 at 11:09:22AM -0400, Jason Baron wrote: > add x86 support for jump label. I'm keeping this patch separate so its clear to > arch maintainers what was required for x86 support this new feature. hopefully, > it wouldn't be too painful for other arches. > > Signed-off-by: Jason Baron > --- > arch/x86/Kconfig | 1 + > arch/x86/include/asm/jump_label.h | 47 +++++++++++++++++++++++++++++++++++ > arch/x86/kernel/Makefile | 2 +- > arch/x86/kernel/jump_label.c | 49 +++++++++++++++++++++++++++++++++++++ > arch/x86/kernel/module.c | 3 ++ > 5 files changed, 101 insertions(+), 1 deletions(-) > create mode 100644 arch/x86/include/asm/jump_label.h > create mode 100644 arch/x86/kernel/jump_label.c > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 0c14369..a986079 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -60,6 +60,7 @@ config X86 > select ANON_INODES > select HAVE_ARCH_KMEMCHECK > select HAVE_USER_RETURN_NOTIFIER > + select HAVE_ARCH_JUMP_LABEL if !CC_OPTIMIZE_FOR_SIZE > > config INSTRUCTION_DECODER > def_bool (KPROBES || PERF_EVENTS) > diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h > new file mode 100644 > index 0000000..b4a2cb4 > --- /dev/null > +++ b/arch/x86/include/asm/jump_label.h > @@ -0,0 +1,47 @@ > +#ifndef _ASM_X86_JUMP_LABEL_H > +#define _ASM_X86_JUMP_LABEL_H > + > +#ifdef __KERNEL__ > + > +#include > +#include > + > +#define JUMP_LABEL_NOP_SIZE 5 > + > +# define JUMP_LABEL_INITIAL_NOP ".byte 0xe9 \n\t .long 0\n\t" > + > +# define JUMP_LABEL(key, label) \ > + do { \ > + asm goto("1:" \ > + JUMP_LABEL_INITIAL_NOP \ > + ".pushsection __jump_table, \"a\" \n\t"\ > + _ASM_PTR "1b, %l[" #label "], %c0 \n\t" \ > + ".popsection \n\t" \ > + : : "i" (key) : : label); \ > + } while (0) > + > +#endif /* __KERNEL__ */ > + > +#ifdef CONFIG_X86_64 > + > +typedef u64 jump_label_t; > + > +struct jump_entry { > + jump_label_t code; > + jump_label_t target; > + jump_label_t key; > +}; > + > +#else > + > +typedef u32 jump_label_t; > + > +struct jump_entry { > + jump_label_t code; > + jump_label_t target; > + jump_label_t key; The format is the same, why not just put the typedef within the #ifdef? > +}; > + > +#endif > + > +#endif > diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile > index 11a9925..dfa1443 100644 > --- a/arch/x86/kernel/Makefile > +++ b/arch/x86/kernel/Makefile > @@ -32,7 +32,7 @@ GCOV_PROFILE_paravirt.o := n > obj-y := process_$(BITS).o signal.o entry_$(BITS).o > obj-y += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o > obj-y += time.o ioport.o ldt.o dumpstack.o > -obj-y += setup.o x86_init.o i8259.o irqinit.o > +obj-y += setup.o x86_init.o i8259.o irqinit.o jump_label.o > obj-$(CONFIG_X86_VISWS) += visws_quirks.o > obj-$(CONFIG_X86_32) += probe_roms_32.o > obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o > diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c > new file mode 100644 > index 0000000..b3c0f37 > --- /dev/null > +++ b/arch/x86/kernel/jump_label.c > @@ -0,0 +1,49 @@ > +/* > + * jump label x86 support > + * > + * Copyright (C) 2009 Jason Baron Year.