[PATCH 1/3] x86: record relocation offset

Xiao Guangrong
2009-12-30T03:18:51Z

Record relocation offset, perf tools will use it
to adjust kernel symbol address

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
arch/x86/boot/compressed/head_32.S | 2 ++
arch/x86/boot/compressed/head_64.S | 3 +++
arch/x86/include/asm/bootparam.h | 3 ++-
arch/x86/kernel/asm-offsets_32.c | 1 +
arch/x86/kernel/asm-offsets_64.c | 1 +
arch/x86/kernel/cpu/perf_event.c | 4 ++++
6 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index f543b70..dc9748a 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -151,6 +151,8 @@ relocated:
movl %ebp, %ebx
subl $LOAD_PHYSICAL_ADDR, %ebx
jz 2f /* Nothing to be done if loaded at compiled addr. */
+
+ movl %ebx, BP_relocate_offset(%esi)
/*
* Process relocations.
*/
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index faff0dc..8170f32 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -90,6 +90,9 @@ ENTRY(startup_32)
addl %eax, %ebx
notl %eax
andl %eax, %ebx
+ movl %ebx, %eax
+ subl $LOAD_PHYSICAL_ADDR, %eax
+ movl %eax, BP_relocate_offset(%esi)
#else
movl $LOAD_PHYSICAL_ADDR, %ebx
#endif
diff --git a/arch/x86/include/asm/bootparam.h b/arch/x86/include/asm/bootparam.h
index 6be33d8..80b8d1f 100644
--- a/arch/x86/include/asm/bootparam.h
+++ b/arch/x86/include/asm/bootparam.h
@@ -88,7 +88,8 @@ struct boot_params {
__u8 _pad2[4]; /* 0x054 */
__u64 tboot_addr; /* 0x058 */
struct ist_info ist_info; /* 0x060 */
- __u8 _pad3[16]; /* 0x070 */
+ __s32 relocate_offset; /* 0x070 */
+ __u8 _pad3[12]; /* 0x074 */
__u8 hd0_info[16]; /* obsolete! */ /* 0x080 */
__u8 hd1_info[16]; /* obsolete! */ /* 0x090 */
struct sys_desc_table sys_desc_table; /* 0x0a0 */
diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c
index dfdbf64..8028e3b 100644
--- a/arch/x86/kernel/asm-offsets_32.c
+++ b/arch/x86/kernel/asm-offsets_32.c
@@ -148,4 +148,5 @@ void foo(void)
OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
OFFSET(BP_version, boot_params, hdr.version);
OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment);
+ OFFSET(BP_relocate_offset, boot_params, relocate_offset);
}
diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c
index 4a6aeed..fbfa5f3 100644
--- a/arch/x86/kernel/asm-offsets_64.c
+++ b/arch/x86/kernel/asm-offsets_64.c
@@ -127,6 +127,7 @@ int main(void)
OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
OFFSET(BP_version, boot_params, hdr.version);
OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment);
+ OFFSET(BP_relocate_offset, boot_params, relocate_offset);

BLANK();
DEFINE(PAGE_SIZE_asm, PAGE_SIZE);
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index c223b7e..11d2a7d 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -26,8 +26,10 @@
#include <asm/apic.h>
#include <asm/stacktrace.h>
#include <asm/nmi.h>
+#include <asm/setup.h>

static u64 perf_event_mask __read_mostly;
+static s32 relocate_offset;

/* The maximal number of PEBS events: */
#define MAX_PEBS_EVENTS 4
@@ -2173,6 +2175,8 @@ void __init init_hw_perf_events(void)

pr_info("Performance Events: ");

+ relocate_offset = boot_params.relocate_offset;
+
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
err = intel_pmu_init();
--
1.6.1.2