dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

[S390] ftrace: add dynamic ftrace support 

Dynamic ftrace support for s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2009-06-12 10:26:44 +02:00 committed by Martin Schwidefsky
parent a2b53673fa
commit dfd9f7abc0
10 changed files with 281 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/s390/Kconfig
View File

@ -82,6 +82,8 @@ config S390
select USE_GENERIC_SMP_HELPERS if SMP
select HAVE_SYSCALL_WRAPPERS
select HAVE_FUNCTION_TRACER
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
select HAVE_DEFAULT_NO_SPIN_MUTEXES
select HAVE_OPROFILE
select HAVE_KPROBES

19
arch/s390/include/asm/ftrace.h
View File

@ -2,7 +2,26 @@
#define _ASM_S390_FTRACE_H
#ifndef __ASSEMBLY__
extern void _mcount(void);
extern unsigned long ftrace_dyn_func;
struct dyn_arch_ftrace { };
#define MCOUNT_ADDR ((long)_mcount)
#ifdef CONFIG_64BIT
#define MCOUNT_INSN_SIZE 24
#define MCOUNT_OFFSET 14
#else
#define MCOUNT_INSN_SIZE 30
#define MCOUNT_OFFSET 8
#endif
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
return addr - MCOUNT_OFFSET;
}
#endif /* __ASSEMBLY__ */
#endif /* _ASM_S390_FTRACE_H */

8
arch/s390/include/asm/lowcore.h
View File

@ -68,6 +68,7 @@
#define __LC_CPUID 0x02b0
#define __LC_INT_CLOCK 0x02c8
#define __LC_MACHINE_FLAGS 0x02d8
#define __LC_FTRACE_FUNC 0x02dc
#define __LC_IRB 0x0300
#define __LC_PFAULT_INTPARM 0x0080
#define __LC_CPU_TIMER_SAVE_AREA 0x00d8
@ -113,6 +114,7 @@
#define __LC_INT_CLOCK 0x0340
#define __LC_VDSO_PER_CPU 0x0350
#define __LC_MACHINE_FLAGS 0x0358
#define __LC_FTRACE_FUNC 0x0360
#define __LC_IRB 0x0380
#define __LC_PASTE 0x03c0
#define __LC_PFAULT_INTPARM 0x11b8
@ -281,7 +283,8 @@ struct _lowcore
__u64 int_clock; /* 0x02c8 */
__u64 clock_comparator; /* 0x02d0 */
__u32 machine_flags; /* 0x02d8 */
__u8 pad_0x02dc[0x0300-0x02dc]; /* 0x02dc */
__u32 ftrace_func; /* 0x02dc */
__u8 pad_0x02f0[0x0300-0x02f0]; /* 0x02f0 */
/* Interrupt response block */
__u8 irb[64]; /* 0x0300 */
@ -386,7 +389,8 @@ struct _lowcore
__u64 clock_comparator; /* 0x0348 */
__u64 vdso_per_cpu_data; /* 0x0350 */
__u64 machine_flags; /* 0x0358 */
__u8 pad_0x0360[0x0380-0x0360]; /* 0x0360 */
__u64 ftrace_func; /* 0x0360 */
__u8 pad_0x0368[0x0380-0x0368]; /* 0x0368 */
/* Interrupt response block. */
__u8 irb[64]; /* 0x0380 */

5
arch/s390/kernel/Makefile
View File

@ -7,6 +7,10 @@ ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_early.o = -pg
endif
ifdef CONFIG_DYNAMIC_FTRACE
CFLAGS_REMOVE_ftrace.o = -pg
endif
#
# Passing null pointers is ok for smp code, since we access the lowcore here.
#
@ -41,6 +45,7 @@ obj-$(CONFIG_COMPAT) += compat_linux.o compat_signal.o \
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_FUNCTION_TRACER) += mcount.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
# Kexec part
S390_KEXEC_OBJS := machine_kexec.o crash.o

4
arch/s390/kernel/early.c
View File

@ -11,6 +11,7 @@
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/ftrace.h>
#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/pfn.h>
@ -410,5 +411,8 @@ void __init startup_init(void)
sclp_facilities_detect();
detect_memory_layout(memory_chunk);
S390_lowcore.machine_flags = machine_flags;
#ifdef CONFIG_DYNAMIC_FTRACE
S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
#endif
lockdep_on();
}

132
arch/s390/kernel/ftrace.c Normal file
View File

@ -0,0 +1,132 @@
/*
* Dynamic function tracer architecture backend.
*
* Copyright IBM Corp. 2009
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
*
*/
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <asm/lowcore.h>
void ftrace_disable_code(void);
void ftrace_call_code(void);
void ftrace_nop_code(void);
#define FTRACE_INSN_SIZE 4
#ifdef CONFIG_64BIT
asm(
" .align 4\n"
"ftrace_disable_code:\n"
" j 0f\n"
" .word 0x0024\n"
" lg %r1,"__stringify(__LC_FTRACE_FUNC)"\n"
" basr %r14,%r1\n"
" lg %r14,8(15)\n"
" lgr %r0,%r0\n"
"0:\n");
asm(
" .align 4\n"
"ftrace_nop_code:\n"
" j .+"__stringify(MCOUNT_INSN_SIZE)"\n");
asm(
" .align 4\n"
"ftrace_call_code:\n"
" stg %r14,8(%r15)\n");
#else /* CONFIG_64BIT */
asm(
" .align 4\n"
"ftrace_disable_code:\n"
" j 0f\n"
" l %r1,"__stringify(__LC_FTRACE_FUNC)"\n"
" basr %r14,%r1\n"
" l %r14,4(%r15)\n"
" j 0f\n"
" bcr 0,%r7\n"
" bcr 0,%r7\n"
" bcr 0,%r7\n"
" bcr 0,%r7\n"
" bcr 0,%r7\n"
" bcr 0,%r7\n"
"0:\n");
asm(
" .align 4\n"
"ftrace_nop_code:\n"
" j .+"__stringify(MCOUNT_INSN_SIZE)"\n");
asm(
" .align 4\n"
"ftrace_call_code:\n"
" st %r14,4(%r15)\n");
#endif /* CONFIG_64BIT */
static int ftrace_modify_code(unsigned long ip,
void *old_code, int old_size,
void *new_code, int new_size)
{
unsigned char replaced[MCOUNT_INSN_SIZE];
/*
* Note: Due to modules code can disappear and change.
* We need to protect against faulting as well as code
* changing. We do this by using the probe_kernel_*
* functions.
* This however is just a simple sanity check.
*/
if (probe_kernel_read(replaced, (void *)ip, old_size))
return -EFAULT;
if (memcmp(replaced, old_code, old_size) != 0)
return -EINVAL;
if (probe_kernel_write((void *)ip, new_code, new_size))
return -EPERM;
return 0;
}
static int ftrace_make_initial_nop(struct module *mod, struct dyn_ftrace *rec,
unsigned long addr)
{
return ftrace_modify_code(rec->ip,
ftrace_call_code, FTRACE_INSN_SIZE,
ftrace_disable_code, MCOUNT_INSN_SIZE);
}
int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
unsigned long addr)
{
if (addr == MCOUNT_ADDR)
return ftrace_make_initial_nop(mod, rec, addr);
return ftrace_modify_code(rec->ip,
ftrace_call_code, FTRACE_INSN_SIZE,
ftrace_nop_code, FTRACE_INSN_SIZE);
}
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
return ftrace_modify_code(rec->ip,
ftrace_nop_code, FTRACE_INSN_SIZE,
ftrace_call_code, FTRACE_INSN_SIZE);
}
int ftrace_update_ftrace_func(ftrace_func_t func)
{
ftrace_dyn_func = (unsigned long)func;
return 0;
}
int __init ftrace_dyn_arch_init(void *data)
{
*(unsigned long *)data = 0;
return 0;
}

129
arch/s390/kernel/mcount.S
View File

@ -1,5 +1,5 @@
/*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
*
@ -7,10 +7,101 @@
#include <asm/asm-offsets.h>
#ifndef CONFIG_64BIT
.globl _mcount
.globl ftrace_stub
ftrace_stub:
br %r14
#ifdef CONFIG_64BIT
#ifdef CONFIG_DYNAMIC_FTRACE
.globl _mcount
_mcount:
stm %r0,%r5,8(%r15)
br %r14
.globl ftrace_caller
ftrace_caller:
stmg %r2,%r5,32(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
aghi %r15,-160
stg %r1,__SF_BACKCHAIN(%r15)
lgr %r2,%r14
lg %r3,168(%r15)
larl %r14,ftrace_dyn_func
lg %r14,0(%r14)
basr %r14,%r14
aghi %r15,160
lmg %r2,%r5,32(%r15)
lg %r14,112(%r15)
br %r14
.data
.globl ftrace_dyn_func
ftrace_dyn_func:
.quad ftrace_stub
.previous
#else /* CONFIG_DYNAMIC_FTRACE */
.globl _mcount
_mcount:
stmg %r2,%r5,32(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
aghi %r15,-160
stg %r1,__SF_BACKCHAIN(%r15)
lgr %r2,%r14
lg %r3,168(%r15)
larl %r14,ftrace_trace_function
lg %r14,0(%r14)
basr %r14,%r14
aghi %r15,160
lmg %r2,%r5,32(%r15)
lg %r14,112(%r15)
br %r14
#endif /* CONFIG_DYNAMIC_FTRACE */
#else /* CONFIG_64BIT */
#ifdef CONFIG_DYNAMIC_FTRACE
.globl _mcount
_mcount:
br %r14
.globl ftrace_caller
ftrace_caller:
stm %r2,%r5,16(%r15)
st %r14,56(%r15)
lr %r1,%r15
ahi %r15,-96
l %r3,100(%r15)
la %r2,0(%r14)
st %r1,__SF_BACKCHAIN(%r15)
la %r3,0(%r3)
bras %r14,0f
.long ftrace_dyn_func
0: l %r14,0(%r14)
l %r14,0(%r14)
basr %r14,%r14
ahi %r15,96
lm %r2,%r5,16(%r15)
l %r14,56(%r15)
br %r14
.data
.globl ftrace_dyn_func
ftrace_dyn_func:
.long ftrace_stub
.previous
#else /* CONFIG_DYNAMIC_FTRACE */
.globl _mcount
_mcount:
stm %r2,%r5,16(%r15)
st %r14,56(%r15)
lr %r1,%r15
ahi %r15,-96
@ -24,35 +115,9 @@ _mcount:
l %r14,0(%r14)
basr %r14,%r14
ahi %r15,96
lm %r0,%r5,8(%r15)
lm %r2,%r5,16(%r15)
l %r14,56(%r15)
br %r14
.globl ftrace_stub
ftrace_stub:
br %r14
#else /* CONFIG_64BIT */
.globl _mcount
_mcount:
stmg %r0,%r5,16(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
aghi %r15,-160
stg %r1,__SF_BACKCHAIN(%r15)
lgr %r2,%r14
lg %r3,168(%r15)
larl %r14,ftrace_trace_function
lg %r14,0(%r14)
basr %r14,%r14
aghi %r15,160
lmg %r0,%r5,16(%r15)
lg %r14,112(%r15)
br %r14
.globl ftrace_stub
ftrace_stub:
br %r14
#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* CONFIG_64BIT */

2
arch/s390/kernel/setup.c
View File

@ -42,6 +42,7 @@
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <linux/topology.h>
#include <linux/ftrace.h>
#include <asm/ipl.h>
#include <asm/uaccess.h>
@ -442,6 +443,7 @@ setup_lowcore(void)
lc->steal_timer = S390_lowcore.steal_timer;
lc->last_update_timer = S390_lowcore.last_update_timer;
lc->last_update_clock = S390_lowcore.last_update_clock;
lc->ftrace_func = S390_lowcore.ftrace_func;
set_prefix((u32)(unsigned long) lc);
lowcore_ptr[0] = lc;
}

1
arch/s390/kernel/smp.c
View File

@ -572,6 +572,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
cpu_lowcore->cpu_nr = cpu;
cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
cpu_lowcore->machine_flags = S390_lowcore.machine_flags;
cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func;
eieio();
while (signal_processor(cpu, sigp_restart) == sigp_busy)

13
scripts/recordmcount.pl
View File

@ -185,6 +185,19 @@ if ($arch eq "x86_64") {
$objcopy .= " -O elf32-i386";
$cc .= " -m32";
} elsif ($arch eq "s390" && $bits == 32) {
$mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_390_32\\s+_mcount\$";
$alignment = 4;
$ld .= " -m elf_s390";
$cc .= " -m31";
} elsif ($arch eq "s390" && $bits == 64) {
$mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_390_(PC|PLT)32DBL\\s+_mcount\\+0x2\$";
$alignment = 8;
$type = ".quad";
$ld .= " -m elf64_s390";
$cc .= " -m64";
} elsif ($arch eq "sh") {
$alignment = 2;