[for-next][PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
From: Namhyung Kim 

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N >= 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee 
Acked-by: Masami Hiramatsu 
Acked-by: Oleg Nesterov 
Cc: Srikar Dronamraju 
Cc: Oleg Nesterov 
Cc: zhangwei(Jovi) 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Hyeoncheol Lee 
Signed-off-by: Namhyung Kim 
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b89..6e5cff2 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N >= 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a "null-terminated" string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ b@/
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 8f7a2b6d..a130d61 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -255,12 +255,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, "stack", 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f->fn = fetch_stack_address;
+   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f->fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f->fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, );
-   if (ret || param > PARAM_MAX_STACK)
+   if (ret || (is_kprobe && param > PARAM_MAX_STACK))
ret = -EINVAL;

Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Fri, 3 Jan 2014 10:17:23 +0900
"Hyeoncheol Lee"  wrote:

> Patches look good to me.
> 
> Signed-off-by: Hyeoncheol Lee 
> 

Thanks! I'll add this to my queue.

-- Steve
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RE: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Hyeoncheol Lee 
Patches look good to me.

Signed-off-by: Hyeoncheol Lee 

-Original Message-
From: Steven Rostedt [mailto:rost...@goodmis.org] 
Sent: Friday, January 03, 2014 6:02 AM
To: Steven Rostedt
Cc: Namhyung Kim; Oleg Nesterov; Masami Hiramatsu; Srikar Dronamraju;
Hyeoncheol Lee; zhangwei(Jovi); Arnaldo Carvalho de Melo; Hemant Kumar;
LKML; Namhyung Kim
Subject: Re: [PATCH 15/17] tracing/uprobes: Add support for full argument
access methods

On Thu, 2 Jan 2014 15:58:27 -0500
Steven Rostedt  wrote:

> On Mon, 16 Dec 2013 13:32:14 +0900
> Namhyung Kim  wrote:
> 
> > From: Namhyung Kim 
> > 
> > Enable to fetch other types of argument for the uprobes.  IOW, we 
> > can access stack, memory, deref, bitfield and retval from uprobes now.
> > 
> > The format for the argument types are same as kprobes (but @SYMBOL 
> > type is not supported for uprobes), i.e:
> > 
> >   @ADDR   : Fetch memory at ADDR
> >   $stackN : Fetch Nth entry of stack (N >= 0)
> >   $stack  : Fetch stack address
> >   $retval : Fetch return value
> >   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
> > 
> > Note that the retval only can be used with uretprobes.
> > 
> > Original-patch-by: Hyeoncheol Lee 
> 
> Where was the original patch posted? And can we get Hyeoncheol's SOB 
> for this?
> 

Was this the other part of patch 11? Still should have Hyeoncheol's
signed-off-by. If you already had it on the original (before the split) then
we can add it here too, as he already signed off on the code that this was
based on.

-- Steve

--
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Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Thu, 2 Jan 2014 15:58:27 -0500
Steven Rostedt  wrote:

> On Mon, 16 Dec 2013 13:32:14 +0900
> Namhyung Kim  wrote:
> 
> > From: Namhyung Kim 
> > 
> > Enable to fetch other types of argument for the uprobes.  IOW, we can
> > access stack, memory, deref, bitfield and retval from uprobes now.
> > 
> > The format for the argument types are same as kprobes (but @SYMBOL
> > type is not supported for uprobes), i.e:
> > 
> >   @ADDR   : Fetch memory at ADDR
> >   $stackN : Fetch Nth entry of stack (N >= 0)
> >   $stack  : Fetch stack address
> >   $retval : Fetch return value
> >   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
> > 
> > Note that the retval only can be used with uretprobes.
> > 
> > Original-patch-by: Hyeoncheol Lee 
> 
> Where was the original patch posted? And can we get Hyeoncheol's SOB for
> this?
> 

Was this the other part of patch 11? Still should have Hyeoncheol's
signed-off-by. If you already had it on the original (before the split)
then we can add it here too, as he already signed off on the code that
this was based on.

-- Steve
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Mon, 16 Dec 2013 13:32:14 +0900
Namhyung Kim  wrote:

> From: Namhyung Kim 
> 
> Enable to fetch other types of argument for the uprobes.  IOW, we can
> access stack, memory, deref, bitfield and retval from uprobes now.
> 
> The format for the argument types are same as kprobes (but @SYMBOL
> type is not supported for uprobes), i.e:
> 
>   @ADDR   : Fetch memory at ADDR
>   $stackN : Fetch Nth entry of stack (N >= 0)
>   $stack  : Fetch stack address
>   $retval : Fetch return value
>   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
> 
> Note that the retval only can be used with uretprobes.
> 
> Original-patch-by: Hyeoncheol Lee 

Where was the original patch posted? And can we get Hyeoncheol's SOB for
this?

Thanks!

-- Steve

> Acked-by: Masami Hiramatsu 
> Cc: Srikar Dronamraju 
> Cc: Oleg Nesterov 
> Cc: zhangwei(Jovi) 
> Cc: Arnaldo Carvalho de Melo 
> Signed-off-by: Namhyung Kim 
> ---
>  Documentation/trace/uprobetracer.txt | 25 +
>  kernel/trace/trace_probe.c   | 34 ++
>  2 files changed, 47 insertions(+), 12 deletions(-)
> 
> diff --git a/Documentation/trace/uprobetracer.txt 
> b/Documentation/trace/uprobetracer.txt
> index 8f1a8b8956fc..6e5cff263e2b 100644
> --- a/Documentation/trace/uprobetracer.txt
> +++ b/Documentation/trace/uprobetracer.txt
> @@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
>  
>FETCHARGS : Arguments. Each probe can have up to 128 args.
> %REG : Fetch register REG
> +   @ADDR : Fetch memory at ADDR (ADDR should be in userspace)
> +   $stackN   : Fetch Nth entry of stack (N >= 0)
> +   $stack: Fetch stack address.
> +   $retval   : Fetch return value.(*)
> +   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
> +   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
> +   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic 
> types
> +(u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
> +are supported.
> +
> +  (*) only for return probe.
> +  (**) this is useful for fetching a field of data structures.
> +
> +Types
> +-
> +Several types are supported for fetch-args. Uprobe tracer will access memory
> +by given type. Prefix 's' and 'u' means those types are signed and unsigned
> +respectively. Traced arguments are shown in decimal (signed) or hex 
> (unsigned).
> +String type is a special type, which fetches a "null-terminated" string from
> +user space.
> +Bitfield is another special type, which takes 3 parameters, bit-width, bit-
> +offset, and container-size (usually 32). The syntax is;
> +
> + b@/
> +
>  
>  Event Profiling
>  ---
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> index 8f7a2b6d389d..a130d612e705 100644
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -255,12 +255,18 @@ fail:
>  }
>  
>  /* Special function : only accept unsigned long */
> -static __kprobes void fetch_stack_address(struct pt_regs *regs,
> - void *dummy, void *dest)
> +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
> +  void *dummy, void *dest)
>  {
>   *(unsigned long *)dest = kernel_stack_pointer(regs);
>  }
>  
> +static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
> +void *dummy, void *dest)
> +{
> + *(unsigned long *)dest = user_stack_pointer(regs);
> +}
> +
>  static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
>   fetch_func_t orig_fn,
>   const struct fetch_type *ftbl)
> @@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
> long *offset)
>  #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
>  
>  static int parse_probe_vars(char *arg, const struct fetch_type *t,
> - struct fetch_param *f, bool is_return)
> + struct fetch_param *f, bool is_return,
> + bool is_kprobe)
>  {
>   int ret = 0;
>   unsigned long param;
> @@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
> fetch_type *t,
>   ret = -EINVAL;
>   } else if (strncmp(arg, "stack", 5) == 0) {
>   if (arg[5] == '\0') {
> - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
> - f->fn = fetch_stack_address;
> + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
> + return -EINVAL;
> +
> + if (is_kprobe)
> + f->fn = fetch_kernel_stack_address;
>   else
> - ret = -EINVAL;
> + f->fn = fetch_user_stack_address;
>

Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Mon, 16 Dec 2013 13:32:14 +0900
Namhyung Kim namhy...@kernel.org wrote:

 From: Namhyung Kim namhyung@lge.com
 
 Enable to fetch other types of argument for the uprobes.  IOW, we can
 access stack, memory, deref, bitfield and retval from uprobes now.
 
 The format for the argument types are same as kprobes (but @SYMBOL
 type is not supported for uprobes), i.e:
 
   @ADDR   : Fetch memory at ADDR
   $stackN : Fetch Nth entry of stack (N = 0)
   $stack  : Fetch stack address
   $retval : Fetch return value
   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
 
 Note that the retval only can be used with uretprobes.
 
 Original-patch-by: Hyeoncheol Lee cheol@lge.com

Where was the original patch posted? And can we get Hyeoncheol's SOB for
this?

Thanks!

-- Steve

 Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com
 Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com
 Cc: Oleg Nesterov o...@redhat.com
 Cc: zhangwei(Jovi) jovi.zhang...@huawei.com
 Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net
 Signed-off-by: Namhyung Kim namhy...@kernel.org
 ---
  Documentation/trace/uprobetracer.txt | 25 +
  kernel/trace/trace_probe.c   | 34 ++
  2 files changed, 47 insertions(+), 12 deletions(-)
 
 diff --git a/Documentation/trace/uprobetracer.txt 
 b/Documentation/trace/uprobetracer.txt
 index 8f1a8b8956fc..6e5cff263e2b 100644
 --- a/Documentation/trace/uprobetracer.txt
 +++ b/Documentation/trace/uprobetracer.txt
 @@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
  
FETCHARGS : Arguments. Each probe can have up to 128 args.
 %REG : Fetch register REG
 +   @ADDR : Fetch memory at ADDR (ADDR should be in userspace)
 +   $stackN   : Fetch Nth entry of stack (N = 0)
 +   $stack: Fetch stack address.
 +   $retval   : Fetch return value.(*)
 +   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
 +   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
 +   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic 
 types
 +(u8/u16/u32/u64/s8/s16/s32/s64), string and bitfield
 +are supported.
 +
 +  (*) only for return probe.
 +  (**) this is useful for fetching a field of data structures.
 +
 +Types
 +-
 +Several types are supported for fetch-args. Uprobe tracer will access memory
 +by given type. Prefix 's' and 'u' means those types are signed and unsigned
 +respectively. Traced arguments are shown in decimal (signed) or hex 
 (unsigned).
 +String type is a special type, which fetches a null-terminated string from
 +user space.
 +Bitfield is another special type, which takes 3 parameters, bit-width, bit-
 +offset, and container-size (usually 32). The syntax is;
 +
 + bbit-width@bit-offset/container-size
 +
  
  Event Profiling
  ---
 diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
 index 8f7a2b6d389d..a130d612e705 100644
 --- a/kernel/trace/trace_probe.c
 +++ b/kernel/trace/trace_probe.c
 @@ -255,12 +255,18 @@ fail:
  }
  
  /* Special function : only accept unsigned long */
 -static __kprobes void fetch_stack_address(struct pt_regs *regs,
 - void *dummy, void *dest)
 +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
 +  void *dummy, void *dest)
  {
   *(unsigned long *)dest = kernel_stack_pointer(regs);
  }
  
 +static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
 +void *dummy, void *dest)
 +{
 + *(unsigned long *)dest = user_stack_pointer(regs);
 +}
 +
  static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
   fetch_func_t orig_fn,
   const struct fetch_type *ftbl)
 @@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
 long *offset)
  #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
  
  static int parse_probe_vars(char *arg, const struct fetch_type *t,
 - struct fetch_param *f, bool is_return)
 + struct fetch_param *f, bool is_return,
 + bool is_kprobe)
  {
   int ret = 0;
   unsigned long param;
 @@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
 fetch_type *t,
   ret = -EINVAL;
   } else if (strncmp(arg, stack, 5) == 0) {
   if (arg[5] == '\0') {
 - if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0)
 - f-fn = fetch_stack_address;
 + if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR))
 + return -EINVAL;
 +
 + if (is_kprobe)
 + f-fn = fetch_kernel_stack_address;
   else
 -

Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Thu, 2 Jan 2014 15:58:27 -0500
Steven Rostedt rost...@goodmis.org wrote:

 On Mon, 16 Dec 2013 13:32:14 +0900
 Namhyung Kim namhy...@kernel.org wrote:
 
  From: Namhyung Kim namhyung@lge.com
  
  Enable to fetch other types of argument for the uprobes.  IOW, we can
  access stack, memory, deref, bitfield and retval from uprobes now.
  
  The format for the argument types are same as kprobes (but @SYMBOL
  type is not supported for uprobes), i.e:
  
@ADDR   : Fetch memory at ADDR
$stackN : Fetch Nth entry of stack (N = 0)
$stack  : Fetch stack address
$retval : Fetch return value
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
  
  Note that the retval only can be used with uretprobes.
  
  Original-patch-by: Hyeoncheol Lee cheol@lge.com
 
 Where was the original patch posted? And can we get Hyeoncheol's SOB for
 this?
 

Was this the other part of patch 11? Still should have Hyeoncheol's
signed-off-by. If you already had it on the original (before the split)
then we can add it here too, as he already signed off on the code that
this was based on.

-- Steve
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

RE: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Hyeoncheol Lee 
Patches look good to me.

Signed-off-by: Hyeoncheol Lee cheol@lge.com

-Original Message-
From: Steven Rostedt [mailto:rost...@goodmis.org] 
Sent: Friday, January 03, 2014 6:02 AM
To: Steven Rostedt
Cc: Namhyung Kim; Oleg Nesterov; Masami Hiramatsu; Srikar Dronamraju;
Hyeoncheol Lee; zhangwei(Jovi); Arnaldo Carvalho de Melo; Hemant Kumar;
LKML; Namhyung Kim
Subject: Re: [PATCH 15/17] tracing/uprobes: Add support for full argument
access methods

On Thu, 2 Jan 2014 15:58:27 -0500
Steven Rostedt rost...@goodmis.org wrote:

 On Mon, 16 Dec 2013 13:32:14 +0900
 Namhyung Kim namhy...@kernel.org wrote:
 
  From: Namhyung Kim namhyung@lge.com
  
  Enable to fetch other types of argument for the uprobes.  IOW, we 
  can access stack, memory, deref, bitfield and retval from uprobes now.
  
  The format for the argument types are same as kprobes (but @SYMBOL 
  type is not supported for uprobes), i.e:
  
@ADDR   : Fetch memory at ADDR
$stackN : Fetch Nth entry of stack (N = 0)
$stack  : Fetch stack address
$retval : Fetch return value
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address
  
  Note that the retval only can be used with uretprobes.
  
  Original-patch-by: Hyeoncheol Lee cheol@lge.com
 
 Where was the original patch posted? And can we get Hyeoncheol's SOB 
 for this?
 

Was this the other part of patch 11? Still should have Hyeoncheol's
signed-off-by. If you already had it on the original (before the split) then
we can add it here too, as he already signed off on the code that this was
based on.

-- Steve

--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
On Fri, 3 Jan 2014 10:17:23 +0900
Hyeoncheol Lee cheol@lge.com wrote:

 Patches look good to me.
 
 Signed-off-by: Hyeoncheol Lee cheol@lge.com
 

Thanks! I'll add this to my queue.

-- Steve
--
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the body of a message to majord...@vger.kernel.org
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[for-next][PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2014-01-02 Thread Steven Rostedt 
From: Namhyung Kim namhyung@lge.com

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N = 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee cheol@lge.com
Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com
Acked-by: Oleg Nesterov o...@redhat.com
Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com
Cc: Oleg Nesterov o...@redhat.com
Cc: zhangwei(Jovi) jovi.zhang...@huawei.com
Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net
Signed-off-by: Hyeoncheol Lee cheol@lge.com
Signed-off-by: Namhyung Kim namhy...@kernel.org
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b89..6e5cff2 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N = 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), string and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a null-terminated string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ bbit-width@bit-offset/container-size
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 8f7a2b6d..a130d61 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -255,12 +255,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, stack, 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f-fn = fetch_stack_address;
+   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f-fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f-fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret =

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-12-15 Thread Namhyung Kim 
From: Namhyung Kim 

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N >= 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee 
Acked-by: Masami Hiramatsu 
Cc: Srikar Dronamraju 
Cc: Oleg Nesterov 
Cc: zhangwei(Jovi) 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Namhyung Kim 
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N >= 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a "null-terminated" string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ b@/
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 8f7a2b6d389d..a130d612e705 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -255,12 +255,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, "stack", 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f->fn = fetch_stack_address;
+   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f->fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f->fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, );
-   if (ret || param > PARAM_MAX_STACK)
+   if (ret || (is_kprobe && param > PARAM_MAX_STACK))
ret = -EINVAL;
else {

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-12-15 Thread Namhyung Kim 
From: Namhyung Kim namhyung@lge.com

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N = 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee cheol@lge.com
Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com
Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com
Cc: Oleg Nesterov o...@redhat.com
Cc: zhangwei(Jovi) jovi.zhang...@huawei.com
Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net
Signed-off-by: Namhyung Kim namhy...@kernel.org
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N = 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), string and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a null-terminated string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ bbit-width@bit-offset/container-size
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 8f7a2b6d389d..a130d612e705 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -255,12 +255,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, stack, 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f-fn = fetch_stack_address;
+   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f-fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f-fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, param);
-   if (ret || param

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-12-08 Thread Namhyung Kim 
From: Namhyung Kim 

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N >= 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee 
Acked-by: Masami Hiramatsu 
Cc: Srikar Dronamraju 
Cc: Oleg Nesterov 
Cc: zhangwei(Jovi) 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Namhyung Kim 
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N >= 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a "null-terminated" string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ b@/
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index d0b4a42dafcf..464ec506ec08 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -254,12 +254,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -304,7 +310,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -316,13 +323,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, "stack", 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f->fn = fetch_stack_address;
+   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f->fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f->fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, );
-   if (ret || param > PARAM_MAX_STACK)
+   if (ret || (is_kprobe && param > PARAM_MAX_STACK))
ret = -EINVAL;
else {

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-12-08 Thread Namhyung Kim 
From: Namhyung Kim namhyung@lge.com

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N = 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee cheol@lge.com
Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com
Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com
Cc: Oleg Nesterov o...@redhat.com
Cc: zhangwei(Jovi) jovi.zhang...@huawei.com
Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net
Signed-off-by: Namhyung Kim namhy...@kernel.org
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N = 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), string and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a null-terminated string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ bbit-width@bit-offset/container-size
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index d0b4a42dafcf..464ec506ec08 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -254,12 +254,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -304,7 +310,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -316,13 +323,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, stack, 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f-fn = fetch_stack_address;
+   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f-fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f-fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, param);
-   if (ret || param

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-11-26 Thread Namhyung Kim 
From: Namhyung Kim 

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N >= 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee 
Acked-by: Masami Hiramatsu 
Cc: Srikar Dronamraju 
Cc: Oleg Nesterov 
Cc: zhangwei(Jovi) 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Namhyung Kim 
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N >= 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a "null-terminated" string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ b@/
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 01cbc035dcba..1be603d45811 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -254,12 +254,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -304,7 +310,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -316,13 +323,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, "stack", 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f->fn = fetch_stack_address;
+   if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f->fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f->fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, );
-   if (ret || param > PARAM_MAX_STACK)
+   if (ret || (is_kprobe && param > PARAM_MAX_STACK))
ret = -EINVAL;
else {

[PATCH 15/17] tracing/uprobes: Add support for full argument access methods

2013-11-26 Thread Namhyung Kim 
From: Namhyung Kim namhyung@lge.com

Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N = 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee cheol@lge.com
Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com
Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com
Cc: Oleg Nesterov o...@redhat.com
Cc: zhangwei(Jovi) jovi.zhang...@huawei.com
Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net
Signed-off-by: Namhyung Kim namhy...@kernel.org
---
 Documentation/trace/uprobetracer.txt | 25 +
 kernel/trace/trace_probe.c   | 34 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Documentation/trace/uprobetracer.txt 
b/Documentation/trace/uprobetracer.txt
index 8f1a8b8956fc..6e5cff263e2b 100644
--- a/Documentation/trace/uprobetracer.txt
+++ b/Documentation/trace/uprobetracer.txt
@@ -31,6 +31,31 @@ Synopsis of uprobe_tracer
 
   FETCHARGS : Arguments. Each probe can have up to 128 args.
%REG : Fetch register REG
+   @ADDR   : Fetch memory at ADDR (ADDR should be in userspace)
+   $stackN : Fetch Nth entry of stack (N = 0)
+   $stack  : Fetch stack address.
+   $retval : Fetch return value.(*)
+   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
+   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+  (u8/u16/u32/u64/s8/s16/s32/s64), string and bitfield
+  are supported.
+
+  (*) only for return probe.
+  (**) this is useful for fetching a field of data structures.
+
+Types
+-
+Several types are supported for fetch-args. Uprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a null-terminated string from
+user space.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ bbit-width@bit-offset/container-size
+
 
 Event Profiling
 ---
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 01cbc035dcba..1be603d45811 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -254,12 +254,18 @@ fail:
 }
 
 /* Special function : only accept unsigned long */
-static __kprobes void fetch_stack_address(struct pt_regs *regs,
-   void *dummy, void *dest)
+static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs,
+void *dummy, void *dest)
 {
*(unsigned long *)dest = kernel_stack_pointer(regs);
 }
 
+static __kprobes void fetch_user_stack_address(struct pt_regs *regs,
+  void *dummy, void *dest)
+{
+   *(unsigned long *)dest = user_stack_pointer(regs);
+}
+
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
fetch_func_t orig_fn,
const struct fetch_type *ftbl)
@@ -304,7 +310,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned 
long *offset)
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
 static int parse_probe_vars(char *arg, const struct fetch_type *t,
-   struct fetch_param *f, bool is_return)
+   struct fetch_param *f, bool is_return,
+   bool is_kprobe)
 {
int ret = 0;
unsigned long param;
@@ -316,13 +323,16 @@ static int parse_probe_vars(char *arg, const struct 
fetch_type *t,
ret = -EINVAL;
} else if (strncmp(arg, stack, 5) == 0) {
if (arg[5] == '\0') {
-   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0)
-   f-fn = fetch_stack_address;
+   if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR))
+   return -EINVAL;
+
+   if (is_kprobe)
+   f-fn = fetch_kernel_stack_address;
else
-   ret = -EINVAL;
+   f-fn = fetch_user_stack_address;
} else if (isdigit(arg[5])) {
ret = kstrtoul(arg + 5, 10, param);
-   if (ret || param