public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCHSET 00/13] tracing/uprobes: Add support for more fetch methods (v2)
@ 2013-07-31  9:03 Namhyung Kim
  2013-07-31  9:03 ` [PATCH 01/13] tracing/kprobes: Move fetch functions to trace_kprobe.c Namhyung Kim
                   ` (12 more replies)
  0 siblings, 13 replies; 33+ messages in thread
From: Namhyung Kim @ 2013-07-31  9:03 UTC (permalink / raw)
  To: Steven Rostedt
  Cc: Namhyung Kim, Hyeoncheol Lee, LKML, Masami Hiramatsu,
	Srikar Dronamraju, Oleg Nesterov, zhangwei(Jovi),
	Arnaldo Carvalho de Melo

Hello,

This patchset implements memory (address), stack[N], deference,
bitfield and retval (it needs uretprobe tho) fetch methods for
uprobes.  It's based on the previous work [1] done by Hyeoncheol Lee.

Now kprobes and uprobes have their own fetch_type_tables and, in turn,
memory and stack access methods.  Other fetch methods are shared.

For the dereference method, I added a new argument to fetch functions.
It's because for uprobes it needs to know whether the given address is
a file offset or a virtual address in an user process.  For instance,
in case of fetching from a memory directly (like @offset) it should
convert the address (offset) to a virtual address of the process, but
if it's a dereferencing, the given address already has the virtual
address.

To determine this in a fetch function, I passed a pointer to
trace_uprobe for direct fetch, and passed NULL for dereference.


[1] https://lkml.org/lkml/2012/11/14/84

Simple example:

  # cat foo.c
  int glob = -1;
  char str[] = "hello uprobe.";

  struct foo {
    unsigned int unused: 2;
    unsigned int foo: 20;
    unsigned int bar: 10;
  } foo = {
    .foo = 5,
  };

  int main(int argc, char *argv[])
  {
    long local = 0x1234;

    return 127;
  }

  # gcc -o foo -g foo.c

  # objdump -d foo | grep -A9 -F '<main>'
  00000000004004b0 <main>:
    4004b0:	55                   	push   %rbp
    4004b1:	48 89 e5             	mov    %rsp,%rbp
    4004b4:	89 7d ec             	mov    %edi,-0x14(%rbp)
    4004b7:	48 89 75 e0          	mov    %rsi,-0x20(%rbp)
    4004bb:	48 c7 45 f8 34 12 00 	movq   $0x1234,-0x8(%rbp)
    4004c2:	00 
    4004c3:	b8 7f 00 00 00       	mov    $0x7f,%eax
    4004c8:	5d                   	pop    %rbp
    4004c9:	c3                   	retq   

  # nm foo | grep -e glob$ -e str -e foo
  00000000006008bc D foo
  00000000006008a8 D glob
  00000000006008ac D str

  # perf probe -x /home/namhyung/tmp/foo -a 'foo=main+0x13 glob=@0x8a8:s32 \
  > str=@0x8ac:string bit=@0x8bc:b10@2/32 argc=%di local=-0x8(%bp)'
  Added new event:
    probe_foo:foo      (on 0x4c3 with glob=@0x8a8:s32 str=@0x8ac:string 
                                 bit=@0x8bc:b10@2/32 argc=%di local=-0x8(%bp))

  You can now use it in all perf tools, such as:

          perf record -e probe_foo:foo -aR sleep 1

  # perf record -e probe_foo:foo ./foo
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data (~33 samples) ]

  # perf script | grep -v ^#
               foo  2008 [002  2199.867154: probe_foo:foo (4004c3)
                   glob=-1 str="hello uprobe." bit=5 argc=1 local=1234


This patchset is based on the current for-next branch of the Steven
Rostedt's linux-trace tree.  I also put this on my 'uprobe/fetch-v2'
branch in my tree:

  git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git


Any comments are welcome, thanks.
Namhyung


Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>


Hyeoncheol Lee (2):
  tracing/kprobes: Move fetch functions to trace_kprobe.c
  tracing/kprobes: Add fetch{,_size} member into symbol and deref fetch
    method

Namhyung Kim (11):
  tracing/kprobes: Make stack and memory fetch functions static
  tracing/kprobes: Factor out struct trace_probe
  tracing/uprobes: Convert to struct trace_probe
  tracing/kprobes: Move common functions to trace_probe.c
  tracing/kprobes: Remove duplicate set_print_fmt()
  tracing/uprobes: Fetch args before reserving a ring buffer
  tracing/uprobes: Fix a comment for uprobe registration syntax
  tracing/kprobes: Add priv argument to fetch functions
  tracing/uprobes: Add more fetch functions
  tracing/uprobes: Add support for full argument access methods
  tracing/probes: Fix basic print type functions

 kernel/trace/trace_kprobe.c | 519 ++++++++++++++++++++++----------------------
 kernel/trace/trace_probe.c  | 470 ++++++++++++++++++++-------------------
 kernel/trace/trace_probe.h  | 154 ++++++++++++-
 kernel/trace/trace_uprobe.c | 429 ++++++++++++++++++++++++------------
 4 files changed, 934 insertions(+), 638 deletions(-)

-- 
1.7.11.7


^ permalink raw reply	[flat|nested] 33+ messages in thread

end of thread, other threads:[~2013-08-09  9:15 UTC | newest]

Thread overview: 33+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-07-31  9:03 [PATCHSET 00/13] tracing/uprobes: Add support for more fetch methods (v2) Namhyung Kim
2013-07-31  9:03 ` [PATCH 01/13] tracing/kprobes: Move fetch functions to trace_kprobe.c Namhyung Kim
2013-08-05  5:30   ` Masami Hiramatsu
2013-08-05  8:44     ` Namhyung Kim
2013-07-31  9:03 ` [PATCH 02/13] tracing/kprobes: Add fetch{,_size} member into symbol and deref fetch method Namhyung Kim
2013-08-05  8:19   ` Masami Hiramatsu
2013-08-05  8:58     ` Namhyung Kim
2013-07-31  9:03 ` [PATCH 03/13] tracing/kprobes: Make stack and memory fetch functions static Namhyung Kim
2013-08-05  9:04   ` Masami Hiramatsu
2013-08-09  7:35     ` Namhyung Kim
2013-08-09  9:15       ` Masami Hiramatsu
2013-07-31  9:03 ` [PATCH 04/13] tracing/kprobes: Factor out struct trace_probe Namhyung Kim
2013-08-05  6:00   ` Masami Hiramatsu
2013-08-05  8:49     ` Namhyung Kim
2013-07-31  9:03 ` [PATCH 05/13] tracing/uprobes: Convert to " Namhyung Kim
2013-07-31  9:03 ` [PATCH 06/13] tracing/kprobes: Move common functions to trace_probe.c Namhyung Kim
2013-08-05  6:03   ` Masami Hiramatsu
2013-08-05  8:50     ` Namhyung Kim
2013-07-31  9:03 ` [PATCH 07/13] tracing/kprobes: Remove duplicate set_print_fmt() Namhyung Kim
2013-08-05  6:46   ` Masami Hiramatsu
2013-07-31  9:03 ` [PATCH 08/13] tracing/uprobes: Fetch args before reserving a ring buffer Namhyung Kim
2013-07-31  9:03 ` [PATCH 09/13] tracing/uprobes: Fix a comment for uprobe registration syntax Namhyung Kim
2013-08-05  5:59   ` Masami Hiramatsu
2013-08-05  8:47     ` Namhyung Kim
2013-07-31  9:03 ` [PATCH 10/13] tracing/kprobes: Add priv argument to fetch functions Namhyung Kim
2013-07-31  9:03 ` [PATCH 11/13] tracing/uprobes: Add more " Namhyung Kim
2013-07-31  9:03 ` [PATCH 12/13] tracing/uprobes: Add support for full argument access methods Namhyung Kim
2013-07-31  9:03 ` [PATCH 13/13] tracing/probes: Fix basic print type functions Namhyung Kim
2013-08-05  6:22   ` Masami Hiramatsu
2013-08-05  6:31     ` Joe Perches
2013-08-05  7:27       ` Masami Hiramatsu
2013-08-05  8:55       ` Namhyung Kim
2013-08-05  8:51     ` Namhyung Kim

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox