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

Ye Bin
2024-03-22T06:42:04Z

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

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2.31.1