2024-03-22 06:46:37

by yebin (H)

[permalink] [raw]
Subject: [PATCH v8 0/5] support '%pd' and '%pD' for print file name

During fault locating, the file name needs to be printed based on the
dentry/file address. The offset needs to be calculated each time, which
is troublesome. Similar to printk, kprobe supports printing file names
for dentry/file addresses.

Diff v8 vs v7:
1. Add detail change log for patch[1-2];

Diff v7 vs v6:
1. Squash [1/8] to [3/8] patches into 1 patch;
2. Split readme_msg[] into each patch;

Diff v6 vs v5:
1. Add const for 'bufsize' in PATCH [1];
2. Move PATCH 'tracing/probes: support '%pd/%pD' type for fprobe' after
PATCH "tracing/probes: support '%pd' type for print struct dentry's name".
3. Add requires '"%pd/%pD":README' for testcase.

Diff v5 vs v4:
1. Use glob_match() instead of str_has_suffix(), so remove the first patch;
2. Allocate buffer from heap for expand dentry;
3. Support "%pd/%pD" print type for fprobe;
4. Use $arg1 instead of origin register in test case;
5. Add test case for fprobe;

Diff v4 vs v3:
1. Use "argv[i][idx + 3] == 'd'" instead of "argv[i][strlen(argv[i]) - 1] == 'd'"
to judge print format in PATCH[4/7];

Diff v3 vs v2:
1. Return the index of where the suffix was found in str_has_suffix();

Diff v2 vs v1:
1. Use "%pd/%pD" print format instead of "pd/pD" print format;
2. Add "%pd/%pD" in README;
3. Expand "%pd/%pD" argument before parameter parsing;
4. Add more detail information in ftrace documentation;
5. Add test cases for new print format in selftests/ftrace;


Ye Bin (5):
tracing/probes: support '%pd' type for print struct dentry's name
tracing/probes: support '%pD' type for print struct file's name
Documentation: tracing: add new type '%pd' and '%pD' for kprobe
selftests/ftrace: add kprobe test cases for VFS type "%pd" and "%pD"
selftests/ftrace: add fprobe test cases for VFS type "%pd" and "%pD"

Documentation/trace/kprobetrace.rst | 8 ++-
kernel/trace/trace.c | 2 +-
kernel/trace/trace_fprobe.c | 6 ++
kernel/trace/trace_kprobe.c | 6 ++
kernel/trace/trace_probe.c | 63 +++++++++++++++++++
kernel/trace/trace_probe.h | 2 +
.../ftrace/test.d/dynevent/fprobe_args_vfs.tc | 40 ++++++++++++
.../ftrace/test.d/kprobe/kprobe_args_vfs.tc | 40 ++++++++++++
8 files changed, 164 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_vfs.tc

--
2.31.1



2024-03-22 06:59:02

by yebin (H)

[permalink] [raw]
Subject: [PATCH v8 5/5] selftests/ftrace: add fprobe test cases for VFS type "%pd" and "%pD"

This patch adds fprobe test cases for new print format type "%pd/%pD".The
test cases test the following items:
1. Test "%pd" type for dput();
2. Test "%pD" type for vfs_read();

This test case require enable CONFIG_HAVE_FUNCTION_ARG_ACCESS_API configuration.

Signed-off-by: Ye Bin <[email protected]>
---
.../ftrace/test.d/dynevent/fprobe_args_vfs.tc | 40 +++++++++++++++++++
1 file changed, 40 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc

diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc
new file mode 100644
index 000000000000..49a833bf334c
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc
@@ -0,0 +1,40 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Fprobe event VFS type argument
+# requires: kprobe_events "%pd/%pD":README
+
+: "Test argument %pd with name for fprobe"
+echo 'f:testprobe dput name=$arg1:%pd' > dynamic_events
+echo 1 > events/fprobes/testprobe/enable
+grep -q "1" events/fprobes/testprobe/enable
+echo 0 > events/fprobes/testprobe/enable
+grep "dput" trace | grep -q "enable"
+echo "" > dynamic_events
+echo "" > trace
+
+: "Test argument %pd without name for fprobe"
+echo 'f:testprobe dput $arg1:%pd' > dynamic_events
+echo 1 > events/fprobes/testprobe/enable
+grep -q "1" events/fprobes/testprobe/enable
+echo 0 > events/fprobes/testprobe/enable
+grep "dput" trace | grep -q "enable"
+echo "" > dynamic_events
+echo "" > trace
+
+: "Test argument %pD with name for fprobe"
+echo 'f:testprobe vfs_read name=$arg1:%pD' > dynamic_events
+echo 1 > events/fprobes/testprobe/enable
+grep -q "1" events/fprobes/testprobe/enable
+echo 0 > events/fprobes/testprobe/enable
+grep "vfs_read" trace | grep -q "enable"
+echo "" > dynamic_events
+echo "" > trace
+
+: "Test argument %pD without name for fprobe"
+echo 'f:testprobe vfs_read $arg1:%pD' > dynamic_events
+echo 1 > events/fprobes/testprobe/enable
+grep -q "1" events/fprobes/testprobe/enable
+echo 0 > events/fprobes/testprobe/enable
+grep "vfs_read" trace | grep -q "enable"
+echo "" > dynamic_events
+echo "" > trace
--
2.31.1


2024-03-25 08:49:40

by Masami Hiramatsu

[permalink] [raw]
Subject: Re: [PATCH v8 0/5] support '%pd' and '%pD' for print file name

On Fri, 22 Mar 2024 14:43:03 +0800
Ye Bin <[email protected]> wrote:

> During fault locating, the file name needs to be printed based on the
> dentry/file address. The offset needs to be calculated each time, which
> is troublesome. Similar to printk, kprobe supports printing file names
> for dentry/file addresses.
>

Hi Ye,

Thanks for update! There is a nit comment but basically OK.

Acked-by: Masami Hiramatsu (Google) <[email protected]>

Thank you,

> Diff v8 vs v7:
> 1. Add detail change log for patch[1-2];
>
> Diff v7 vs v6:
> 1. Squash [1/8] to [3/8] patches into 1 patch;
> 2. Split readme_msg[] into each patch;
>
> Diff v6 vs v5:
> 1. Add const for 'bufsize' in PATCH [1];
> 2. Move PATCH 'tracing/probes: support '%pd/%pD' type for fprobe' after
> PATCH "tracing/probes: support '%pd' type for print struct dentry's name".
> 3. Add requires '"%pd/%pD":README' for testcase.
>
> Diff v5 vs v4:
> 1. Use glob_match() instead of str_has_suffix(), so remove the first patch;
> 2. Allocate buffer from heap for expand dentry;
> 3. Support "%pd/%pD" print type for fprobe;
> 4. Use $arg1 instead of origin register in test case;
> 5. Add test case for fprobe;
>
> Diff v4 vs v3:
> 1. Use "argv[i][idx + 3] == 'd'" instead of "argv[i][strlen(argv[i]) - 1] == 'd'"
> to judge print format in PATCH[4/7];
>
> Diff v3 vs v2:
> 1. Return the index of where the suffix was found in str_has_suffix();
>
> Diff v2 vs v1:
> 1. Use "%pd/%pD" print format instead of "pd/pD" print format;
> 2. Add "%pd/%pD" in README;
> 3. Expand "%pd/%pD" argument before parameter parsing;
> 4. Add more detail information in ftrace documentation;
> 5. Add test cases for new print format in selftests/ftrace;
>
>
> Ye Bin (5):
> tracing/probes: support '%pd' type for print struct dentry's name
> tracing/probes: support '%pD' type for print struct file's name
> Documentation: tracing: add new type '%pd' and '%pD' for kprobe
> selftests/ftrace: add kprobe test cases for VFS type "%pd" and "%pD"
> selftests/ftrace: add fprobe test cases for VFS type "%pd" and "%pD"
>
> Documentation/trace/kprobetrace.rst | 8 ++-
> kernel/trace/trace.c | 2 +-
> kernel/trace/trace_fprobe.c | 6 ++
> kernel/trace/trace_kprobe.c | 6 ++
> kernel/trace/trace_probe.c | 63 +++++++++++++++++++
> kernel/trace/trace_probe.h | 2 +
> .../ftrace/test.d/dynevent/fprobe_args_vfs.tc | 40 ++++++++++++
> .../ftrace/test.d/kprobe/kprobe_args_vfs.tc | 40 ++++++++++++
> 8 files changed, 164 insertions(+), 3 deletions(-)
> create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/fprobe_args_vfs.tc
> create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_vfs.tc
>
> --
> 2.31.1
>
>


--
Masami Hiramatsu (Google) <[email protected]>