From e3f28c1333acfe9e4109b836bc15caf794e94d09 Mon Sep 17 00:00:00 2001 From: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Date: Sat, 7 Nov 2009 21:03:52 +0000 Subject: ARM: use unified discard definition in linker script Commit 023bf6f "linker script: unify usage of discard definition" changed the linker scripts for all architectures except for ARM. I can find no discussion about this ommision, so here are the changes for ARM. These changes are exactly parallel to the ia64 case. "ia64 is notable because it first throws away some ia64 specific subsections and then include the rest of the sections into the final image, so those sections must be discarded before the inclusion." Not boot-tested. In build testing, the modified linker script generated an identical vmlinux file. [I would like to be able to rely on this unified discard definition. I want to sort the kernel symbol tables to allow faster symbol resolution during module loading. The simplest way appears to be to generate sorted versions from vmlinux.o, link them in to vmlinux, _and discard the original unsorted tables_. This work is driven by my x86 netbook, but it is implemented at a generic level. It is possible it will benefit some ARM systems also.] Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by-without-testing: Tejun Heo <tj@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> --- arch/arm/kernel/vmlinux.lds.S | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 71151bd87a36..4957e13ef55b 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -65,11 +65,11 @@ SECTIONS __init_end = .; #endif - /DISCARD/ : { /* Exit code and data */ - EXIT_TEXT - EXIT_DATA - *(.exitcall.exit) - *(.discard) + /* + * unwind exit sections must be discarded before the rest of the + * unwind sections get included. + */ + /DISCARD/ : { *(.ARM.exidx.exit.text) *(.ARM.extab.exit.text) #ifndef CONFIG_HOTPLUG_CPU @@ -238,6 +238,9 @@ SECTIONS STABS_DEBUG .comment 0 : { *(.comment) } + + /* Default discards */ + DISCARDS } /* -- cgit v1.2.2 From 3e7b19efe621bcf8bfef896c9c4cc5c99c52c3ec Mon Sep 17 00:00:00 2001 From: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Date: Sat, 7 Nov 2009 21:03:53 +0000 Subject: ARM: unexport symbols used to implement floating point emulation The Kconfigs for in-tree floating point emulation do not allow building as modules. That leaves the Acorn FPEmulator module. I found two public releases of this as a binary module for 2.1 and 2.2 kernels, optimized for ARMV4.[1] If there is a resurgence of interest in this, the symbols can always be re-exported. This allows the EXPORT_SYMBOL_ALIAS() hack to be removed. The ulterior motive here is that EXPORT_SYMBOL_ALIAS() makes it harder to sort the resulting kernel symbol tables. Sorted symbol tables will allow faster symbol resolution during module loading. Note that fp_send_sigs() and fp_printk() are simply aliases for existing exports and add no obvious value. Similarly fp_enter could easily be renamed to kern_fp_enter at the point of definition. Therefore removing EXPORT_SYMBOL_ALIAS will not serve as a material obstacle to re-adding the exports should they be desired in future. Build tested only. [1] http://ftp.arm.linux.org.uk/pub/linux/arm/fpemulator/ Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk> CC: Russell King <linux@arm.linux.org.uk> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> --- arch/arm/kernel/armksyms.c | 20 -------------------- 1 file changed, 20 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c index 0e627705f746..8214bfebfaca 100644 --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -48,27 +48,7 @@ extern void __aeabi_uidivmod(void); extern void __aeabi_ulcmp(void); extern void fpundefinstr(void); -extern void fp_enter(void); -/* - * This has a special calling convention; it doesn't - * modify any of the usual registers, except for LR. - */ -#define EXPORT_CRC_ALIAS(sym) __CRC_SYMBOL(sym, "") - -#define EXPORT_SYMBOL_ALIAS(sym,orig) \ - EXPORT_CRC_ALIAS(sym) \ - static const struct kernel_symbol __ksymtab_##sym \ - __used __attribute__((section("__ksymtab"))) = \ - { (unsigned long)&orig, #sym }; - -/* - * floating point math emulator support. - * These symbols will never change their calling convention... - */ -EXPORT_SYMBOL_ALIAS(kern_fp_enter,fp_enter); -EXPORT_SYMBOL_ALIAS(fp_printk,printk); -EXPORT_SYMBOL_ALIAS(fp_send_sig,send_sig); EXPORT_SYMBOL(__backtrace); -- cgit v1.2.2