diff options
| author | Jan Beulich <jbeulich@novell.com> | 2006-10-21 18:37:01 +0200 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2006-10-21 18:37:01 +0200 |
| commit | 690a973f48b6ba2954465992c08e65059c8374fe (patch) | |
| tree | b30a59496628592233944b3f4340cdfdf9d3d5de /include | |
| parent | cdfce1f5714fec7b24715f569b2fee1607350a6d (diff) | |
| download | lwn-690a973f48b6ba2954465992c08e65059c8374fe.tar.gz lwn-690a973f48b6ba2954465992c08e65059c8374fe.zip | |
[PATCH] x86-64: Speed up dwarf2 unwinder
This changes the dwarf2 unwinder to do a binary search for CIEs
instead of a linear work. The linker is unfortunately not
able to build a proper lookup table at link time, instead it creates
one at runtime as soon as the bootmem allocator is usable (so you'll continue
using the linear lookup for the first [hopefully] few calls).
The code should be ready to utilize a build-time created table once
a fixed linker becomes available.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-generic/vmlinux.lds.h | 16 | ||||
| -rw-r--r-- | include/linux/unwind.h | 2 |
2 files changed, 18 insertions, 0 deletions
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 69240b52f8e1..9d0d11c180d9 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -125,6 +125,10 @@ *(__param) \ VMLINUX_SYMBOL(__stop___param) = .; \ } \ + \ + /* Unwind data binary search table */ \ + EH_FRAME_HDR \ + \ __end_rodata = .; \ . = ALIGN(4096); @@ -157,6 +161,18 @@ *(.kprobes.text) \ VMLINUX_SYMBOL(__kprobes_text_end) = .; +#ifdef CONFIG_STACK_UNWIND + /* Unwind data binary search table */ +#define EH_FRAME_HDR \ + .eh_frame_hdr : AT(ADDR(.eh_frame_hdr) - LOAD_OFFSET) { \ + VMLINUX_SYMBOL(__start_unwind_hdr) = .; \ + *(.eh_frame_hdr) \ + VMLINUX_SYMBOL(__end_unwind_hdr) = .; \ + } +#else +#define EH_FRAME_HDR +#endif + /* DWARF debug sections. Symbols in the DWARF debugging sections are relative to the beginning of the section so we begin them at 0. */ diff --git a/include/linux/unwind.h b/include/linux/unwind.h index 73e1751d03dd..749928c161fb 100644 --- a/include/linux/unwind.h +++ b/include/linux/unwind.h @@ -26,6 +26,7 @@ struct module; * Initialize unwind support. */ extern void unwind_init(void); +extern void unwind_setup(void); #ifdef CONFIG_MODULES @@ -73,6 +74,7 @@ extern int unwind_to_user(struct unwind_frame_info *); struct unwind_frame_info {}; static inline void unwind_init(void) {} +static inline void unwind_setup(void) {} #ifdef CONFIG_MODULES |