From: Masami Hiramatsu <mhiramat@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>,
Jiri Olsa <jolsa@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Namhyung Kim <namhyung@kernel.org>,
David Ahern <dsahern@gmail.com>
Subject: [PATCH perf/core 4/4] perf-probe: Match linkage name with mangled name
Date: Sat, 24 Sep 2016 00:35:31 +0900 [thread overview]
Message-ID: <147464493162.29804.16715053505069382443.stgit@devbox> (raw)
In-Reply-To: <147464488719.29804.13099016520754675018.stgit@devbox>
Match linkage name with mangled name if exists. The linkage_name
is used for storing mangled name of the object.
Thus, this allows perf-probe to find appropriate probe point
from mangled symbol as below.
E.g. without this fix:
----
$ ./perf probe -x /usr/lib64/libstdc++.so.6 \
-D _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
Probe point '_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv'
not found.
Error: Failed to add events.
----
With this fix, perf probe can find the correct one.
----
$ ./perf probe -x /usr/lib64/libstdc++.so.6 \
-D _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
p:probe_libstdc/_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
/usr/lib64/libstdc++.so.6.0.22:0x8ca60
----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
tools/perf/util/dwarf-aux.c | 28 ++++++++++++++++++++++++++--
tools/perf/util/dwarf-aux.h | 3 +++
2 files changed, 29 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index faec899..41e068e 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -130,6 +130,22 @@ int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
}
/**
+ * die_get_linkage_name - Get the linkage name of the object
+ * @dw_die: A DIE of the object
+ *
+ * Get the linkage name attiribute of given @dw_die.
+ * For C++ binary, the linkage name will be the mangled symbol.
+ */
+const char *die_get_linkage_name(Dwarf_Die *dw_die)
+{
+ Dwarf_Attribute attr;
+
+ if (dwarf_attr_integrate(dw_die, DW_AT_linkage_name, &attr) == NULL)
+ return NULL;
+ return dwarf_formstring(&attr);
+}
+
+/**
* die_compare_name - Compare diename and tname
* @dw_die: a DIE
* @tname: a string of target name
@@ -145,18 +161,26 @@ bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
}
/**
- * die_match_name - Match diename and glob
+ * die_match_name - Match diename/linkage name and glob
* @dw_die: a DIE
* @glob: a string of target glob pattern
*
* Glob matching the name of @dw_die and @glob. Return false if matching fail.
+ * This also match linkage name.
*/
bool die_match_name(Dwarf_Die *dw_die, const char *glob)
{
const char *name;
name = dwarf_diename(dw_die);
- return name ? strglobmatch(name, glob) : false;
+ if (name && strglobmatch(name, glob))
+ return true;
+ /* fall back to check linkage name */
+ name = die_get_linkage_name(dw_die);
+ if (name && strglobmatch(name, glob))
+ return true;
+
+ return false;
}
/**
diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
index 8b6d2f8..8ac53bf 100644
--- a/tools/perf/util/dwarf-aux.h
+++ b/tools/perf/util/dwarf-aux.h
@@ -38,6 +38,9 @@ int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr,
int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
int (*callback)(Dwarf_Die *, void *), void *data);
+/* Get DW_AT_linkage_name (should be NULL for C binary) */
+const char *die_get_linkage_name(Dwarf_Die *dw_die);
+
/* Ensure that this DIE is a subprogram and definition (not declaration) */
bool die_is_func_def(Dwarf_Die *dw_die);
next prev parent reply other threads:[~2016-09-23 15:35 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-23 15:34 [PATCH perf/core 0/4] perf-probe fixes for C++ Masami Hiramatsu
2016-09-23 15:34 ` [PATCH perf/core 1/4] perf-probe: Ignore the error of finding inline instance Masami Hiramatsu
2016-09-29 18:19 ` [tip:perf/core] perf probe: " tip-bot for Masami Hiramatsu
2016-09-23 15:35 ` [PATCH perf/core 2/4] perf-probe: Skip if the function address is 0 Masami Hiramatsu
2016-09-29 18:19 ` [tip:perf/core] perf probe: " tip-bot for Masami Hiramatsu
2016-09-23 15:35 ` [PATCH perf/core 3/4] perf-probe: Fix to cut off incompatible chars from group name Masami Hiramatsu
2016-09-29 18:20 ` [tip:perf/core] perf probe: " tip-bot for Masami Hiramatsu
2016-09-23 15:35 ` Masami Hiramatsu [this message]
2016-09-29 18:20 ` [tip:perf/core] perf probe: Match linkage name with mangled name tip-bot for Masami Hiramatsu
2016-09-25 11:14 ` [PATCH perf/core 0/4] perf-probe fixes for C++ Jiri Olsa
2016-09-27 18:11 ` Masami Hiramatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=147464493162.29804.16715053505069382443.stgit@devbox \
--to=mhiramat@kernel.org \
--cc=acme@kernel.org \
--cc=dsahern@gmail.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).