From: Sam Ravnborg Date: Mon, 28 Jan 2008 19:21:15 +0000 (+0100) Subject: Introduce new section reference annotations tags: __ref, __refdata, __refconst X-Git-Tag: v2.6.25-rc1~1164^2~2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=312b1485fb509c9bc32eda28ad29537896658cb8;p=linux-2.6 Introduce new section reference annotations tags: __ref, __refdata, __refconst Today we have the following annotations for functions/data referencing __init/__exit functions / data: __init_refok => for init functions __initdata_refok => for init data __exit_refok => for exit functions There is really no difference between the __init and __exit versions and simplify it and to introduce a shorter annotation the following new annotations are introduced: __ref => for functions (code) that references __*init / __*exit __refdata => for variables __refconst => for const variables Whit this annotation is it more obvious what the annotation is for and there is no longer the arbitary division between __init and __exit code. The mechanishm is the same as before - a special section is created which is made part of the usual sections in the linker script. We will start to see annotations like this: -static struct pci_serial_quirk pci_serial_quirks[] = { +static const struct pci_serial_quirk pci_serial_quirks[] __refconst = { ----------------- -static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier = +static struct notifier_block cpuid_class_cpu_notifier __refdata = ---------------- -static int threshold_cpu_callback(struct notifier_block *nfb, +static int __ref threshold_cpu_callback(struct notifier_block *nfb, [The above is just random samples]. Note: No modifications were needed in modpost to support the new sections due to the newly introduced blacklisting. Signed-off-by: Sam Ravnborg --- diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 2948530537..76df771be5 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -42,6 +42,7 @@ #define DATA_DATA \ *(.data) \ *(.data.init.refok) \ + *(.ref.data) \ DEV_KEEP(init.data) \ DEV_KEEP(exit.data) \ CPU_KEEP(init.data) \ @@ -169,6 +170,7 @@ \ /* __*init sections */ \ __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ + *(.ref.rodata) \ DEV_KEEP(init.rodata) \ DEV_KEEP(exit.rodata) \ CPU_KEEP(init.rodata) \ @@ -202,6 +204,7 @@ #define TEXT_TEXT \ ALIGN_FUNCTION(); \ *(.text) \ + *(.ref.text) \ *(.text.init.refok) \ *(.exit.text.refok) \ DEV_KEEP(init.text) \ diff --git a/include/linux/init.h b/include/linux/init.h index dde1eaa776..2efbda0167 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -52,12 +52,26 @@ * when early init has completed so all such references are potential bugs. * For exit sections the same issue exists. * The following markers are used for the cases where the reference to - * the init/exit section (code or data) is valid and will teach modpost - * not to issue a warning. + * the *init / *exit section (code or data) is valid and will teach + * modpost not to issue a warning. * The markers follow same syntax rules as __init / __initdata. */ -#define __init_refok noinline __section(.text.init.refok) -#define __initdata_refok __section(.data.init.refok) -#define __exit_refok noinline __section(.exit.text.refok) +#define __ref __section(.ref.text) noinline +#define __refdata __section(.ref.data) +#define __refconst __section(.ref.rodata) + +/* backward compatibility note + * A few places hardcode the old section names: + * .text.init.refok + * .data.init.refok + * .exit.text.refok + * They should be converted to use the defines from this file + */ + +/* compatibility defines */ +#define __init_refok __ref +#define __initdata_refok __refdata +#define __exit_refok __ref + #ifdef MODULE #define __exitused @@ -93,11 +107,9 @@ /* For assembly routines */ #define __INIT .section ".init.text","ax" -#define __INIT_REFOK .section ".text.init.refok","ax" #define __FINIT .previous #define __INITDATA .section ".init.data","aw" -#define __INITDATA_REFOK .section ".data.init.refok","aw" #define __DEVINIT .section ".devinit.text", "ax" #define __DEVINITDATA .section ".devinit.data", "aw" @@ -108,6 +120,14 @@ #define __MEMINIT .section ".meminit.text", "ax" #define __MEMINITDATA .section ".meminit.data", "aw" +/* silence warnings when references are OK */ +#define __REF .section ".ref.text", "ax" +#define __REFDATA .section ".ref.data", "aw" +#define __REFCONST .section ".ref.rodata", "aw" +/* backward compatibility */ +#define __INIT_REFOK .section __REF +#define __INITDATA_REFOK .section __REFDATA + #ifndef __ASSEMBLY__ /* * Used for initialization calls..