tracing/probes: Implement 'stack' fetch method for uprobes

Use separate method to fetch from stack.  Move existing functions to
trace_kprobe.c and make them static.  Also add new stack fetch
implementation for uprobes.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
This commit is contained in:
Namhyung Kim 2013-11-26 15:21:04 +09:00 committed by Steven Rostedt
parent 34fee3a104
commit 3fd996a295
4 changed files with 66 additions and 26 deletions

View file

@ -88,6 +88,21 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
static int kretprobe_dispatcher(struct kretprobe_instance *ri,
struct pt_regs *regs);
/*
* Kprobes-specific fetch functions
*/
#define DEFINE_FETCH_stack(type) \
static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
void *offset, void *dest) \
{ \
*(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
(unsigned int)((unsigned long)offset)); \
}
DEFINE_BASIC_FETCH_FUNCS(stack)
/* No string on the stack entry */
#define fetch_stack_string NULL
#define fetch_stack_string_size NULL
/* Fetch type information table */
const struct fetch_type kprobes_fetch_type_table[] = {
/* Special types */

View file

@ -70,16 +70,6 @@ __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
/*
* Define macro for basic types - we don't need to define s* types, because
* we have to care only about bitwidth at recording time.
*/
#define DEFINE_BASIC_FETCH_FUNCS(method) \
DEFINE_FETCH_##method(u8) \
DEFINE_FETCH_##method(u16) \
DEFINE_FETCH_##method(u32) \
DEFINE_FETCH_##method(u64)
#define CHECK_FETCH_FUNCS(method, fn) \
(((FETCH_FUNC_NAME(method, u8) == fn) || \
(FETCH_FUNC_NAME(method, u16) == fn) || \
@ -102,18 +92,6 @@ DEFINE_BASIC_FETCH_FUNCS(reg)
#define fetch_reg_string NULL
#define fetch_reg_string_size NULL
#define DEFINE_FETCH_stack(type) \
__kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \
void *offset, void *dest) \
{ \
*(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
(unsigned int)((unsigned long)offset)); \
}
DEFINE_BASIC_FETCH_FUNCS(stack)
/* No string on the stack entry */
#define fetch_stack_string NULL
#define fetch_stack_string_size NULL
#define DEFINE_FETCH_retval(type) \
__kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs, \
void *dummy, void *dest) \

View file

@ -167,10 +167,6 @@ DECLARE_BASIC_FETCH_FUNCS(reg);
#define fetch_reg_string NULL
#define fetch_reg_string_size NULL
DECLARE_BASIC_FETCH_FUNCS(stack);
#define fetch_stack_string NULL
#define fetch_stack_string_size NULL
DECLARE_BASIC_FETCH_FUNCS(retval);
#define fetch_retval_string NULL
#define fetch_retval_string_size NULL
@ -191,6 +187,16 @@ DECLARE_BASIC_FETCH_FUNCS(bitfield);
#define fetch_bitfield_string NULL
#define fetch_bitfield_string_size NULL
/*
* Define macro for basic types - we don't need to define s* types, because
* we have to care only about bitwidth at recording time.
*/
#define DEFINE_BASIC_FETCH_FUNCS(method) \
DEFINE_FETCH_##method(u8) \
DEFINE_FETCH_##method(u16) \
DEFINE_FETCH_##method(u32) \
DEFINE_FETCH_##method(u64)
/* Default (unsigned long) fetch type */
#define __DEFAULT_FETCH_TYPE(t) u##t
#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)

View file

@ -74,6 +74,47 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
static int uretprobe_dispatcher(struct uprobe_consumer *con,
unsigned long func, struct pt_regs *regs);
#ifdef CONFIG_STACK_GROWSUP
static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
{
return addr - (n * sizeof(long));
}
#else
static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
{
return addr + (n * sizeof(long));
}
#endif
static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
{
unsigned long ret;
unsigned long addr = user_stack_pointer(regs);
addr = adjust_stack_addr(addr, n);
if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
return 0;
return ret;
}
/*
* Uprobes-specific fetch functions
*/
#define DEFINE_FETCH_stack(type) \
static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
void *offset, void *dest) \
{ \
*(type *)dest = (type)get_user_stack_nth(regs, \
((unsigned long)offset)); \
}
DEFINE_BASIC_FETCH_FUNCS(stack)
/* No string on the stack entry */
#define fetch_stack_string NULL
#define fetch_stack_string_size NULL
/* Fetch type information table */
const struct fetch_type uprobes_fetch_type_table[] = {
/* Special types */