linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
To: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	acme@kernel.org, mpe@ellerman.id.au
Subject: [RFC PATCH 7/8] perf probe powerpc: Use DWARF info only if necessary
Date: Tue,  9 Dec 2014 23:04:05 +0530	[thread overview]
Message-ID: <50dd0fedb50e3a56ff8f25c44098db3e2a2d6374.1418146300.git.naveen.n.rao@linux.vnet.ibm.com> (raw)
In-Reply-To: <cover.1418146300.git.naveen.n.rao@linux.vnet.ibm.com>
In-Reply-To: <cover.1418146300.git.naveen.n.rao@linux.vnet.ibm.com>

Use symbol table lookups by default if DWARF is not necessary, since
powerpc ABIv2 encodes local entry points in the symbol table and the
function entry address in DWARF may not be appropriate for kprobes,
as described here:
https://sourceware.org/bugzilla/show_bug.cgi?id=17638

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 tools/perf/util/probe-event.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 174c22e..adcdbd2 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2382,6 +2382,14 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 		}
 	}
 
+#if defined(__powerpc64__) && defined(_CALL_ELF) && _CALL_ELF == 2
+	if (!perf_probe_event_need_dwarf(pev)) {
+		ret = find_probe_trace_events_from_map(pev, tevs, max_tevs, target);
+		if (ret > 0)
+			return ret;	/* Found in symbol table */
+	}
+#endif
+
 	/* Convert perf_probe_event with debuginfo */
 	ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, target);
 	if (ret != 0)
-- 
2.1.3

  parent reply	other threads:[~2014-12-09 17:35 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-09 17:33 [RFC PATCH 0/8] Fix perf probe issues on powerpc Naveen N. Rao
2014-12-09 17:33 ` [RFC PATCH 1/8] kprobes: Fix kallsyms lookup across powerpc ABIv1 and ABIv2 Naveen N. Rao
2014-12-10  9:37   ` Michael Ellerman
2014-12-10 10:26     ` Naveen N. Rao
2014-12-09 17:34 ` [RFC PATCH 2/8] perf probe powerpc: Fix symbol fixup issues due to ELF type Naveen N. Rao
2014-12-09 21:07   ` Arnaldo Carvalho de Melo
2014-12-10  9:35     ` Naveen N. Rao
2014-12-10  9:50   ` Michael Ellerman
2014-12-10 10:41     ` Naveen N. Rao
2014-12-09 17:34 ` [RFC PATCH 3/8] perf probe: Improve detection of file/function name in the probe pattern Naveen N. Rao
2014-12-10 10:00   ` Michael Ellerman
2014-12-10 10:59     ` Naveen N. Rao
2014-12-10 11:12       ` Michael Ellerman
2014-12-09 17:34 ` [RFC PATCH 4/8] perf probe powerpc: Handle powerpc dot symbols Naveen N. Rao
2014-12-10 10:01   ` Michael Ellerman
2014-12-09 17:34 ` [RFC PATCH 5/8] perf probe powerpc: Allow matching against " Naveen N. Rao
2014-12-10 10:03   ` Michael Ellerman
2014-12-09 17:34 ` [RFC PATCH 6/8] perf tools powerpc: Fix PPC64 ELF ABIv2 symbol decoding Naveen N. Rao
2014-12-10 10:13   ` Michael Ellerman
2014-12-10 11:21     ` Naveen N. Rao
2014-12-09 17:34 ` Naveen N. Rao [this message]
2014-12-10 10:17   ` [RFC PATCH 7/8] perf probe powerpc: Use DWARF info only if necessary Michael Ellerman
2014-12-10 11:48     ` Naveen N. Rao
2014-12-09 17:34 ` [RFC PATCH 8/8] perf probe powerpc: Fixup function entry if using kallsyms lookup Naveen N. Rao
2014-12-09 21:14   ` Arnaldo Carvalho de Melo
2014-12-10  4:11     ` Ananth N Mavinakayanahalli
2014-12-10  4:12 ` [RFC PATCH 0/8] Fix perf probe issues on powerpc Ananth N Mavinakayanahalli
2015-01-21 12:51 ` Arnaldo Carvalho de Melo
2015-01-21 15:33   ` Naveen N. Rao

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=50dd0fedb50e3a56ff8f25c44098db3e2a2d6374.1418146300.git.naveen.n.rao@linux.vnet.ibm.com \
    --to=naveen.n.rao@linux.vnet.ibm.com \
    --cc=acme@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    /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).