All of lore.kernel.org
 help / color / mirror / Atom feed
From: tip-bot for Ravi Bangoria <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: tglx@linutronix.de, peterz@infradead.org,
	naveen.n.rao@linux.vnet.ibm.com,
	alexander.shishkin@linux.intel.com, linux-kernel@vger.kernel.org,
	hpa@zytor.com, mhiramat@kernel.org, acme@redhat.com,
	bsingharora@gmail.com, mingo@kernel.org,
	ravi.bangoria@linux.vnet.ibm.com
Subject: [tip:perf/urgent] perf uretprobe ppc64le: Fix probe location
Date: Thu, 6 Oct 2016 15:40:01 -0700	[thread overview]
Message-ID: <tip-a1d9972e59e15538458c030affbfc298c32a47f8@git.kernel.org> (raw)
In-Reply-To: <1475576865-6562-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com>

Commit-ID:  a1d9972e59e15538458c030affbfc298c32a47f8
Gitweb:     http://git.kernel.org/tip/a1d9972e59e15538458c030affbfc298c32a47f8
Author:     Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
AuthorDate: Tue, 4 Oct 2016 15:57:45 +0530
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 5 Oct 2016 08:14:22 -0300

perf uretprobe ppc64le: Fix probe location

Perf uretprobe probes on GEP(Global Entry Point) which fails to record
all function calls via LEP(Local Entry Point). Fix that by probing on LEP.

Objdump:

  00000000100005f0 <doit>:
      100005f0:   02 10 40 3c     lis     r2,4098
      100005f4:   00 7f 42 38     addi    r2,r2,32512
      100005f8:   a6 02 08 7c     mflr    r0
      100005fc:   10 00 01 f8     std     r0,16(r1)
      10000600:   f8 ff e1 fb     std     r31,-8(r1)

Before applying patch:

  $ cat /sys/kernel/debug/tracing/uprobe_events
    r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f0

After applying patch:

  $ cat /sys/kernel/debug/tracing/uprobe_events
    r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f8

This is not the case with kretprobes because the kernel itself finds LEP
and probes on it.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1475576865-6562-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/arch/powerpc/util/sym-handling.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c
index ed9d5d1..1030a6e 100644
--- a/tools/perf/arch/powerpc/util/sym-handling.c
+++ b/tools/perf/arch/powerpc/util/sym-handling.c
@@ -82,7 +82,8 @@ void arch__fix_tev_from_maps(struct perf_probe_event *pev,
 	 *
 	 * In addition, we shouldn't specify an offset for kretprobes.
 	 */
-	if (pev->point.offset || pev->point.retprobe || !map || !sym)
+	if (pev->point.offset || (!pev->uprobes && pev->point.retprobe) ||
+	    !map || !sym)
 		return;
 
 	lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym);

      reply	other threads:[~2016-10-06 22:42 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-04 10:27 [PATCH] perf uretprobe ppc64le: Fix probe location Ravi Bangoria
2016-10-06 22:40 ` tip-bot for Ravi Bangoria [this message]

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=tip-a1d9972e59e15538458c030affbfc298c32a47f8@git.kernel.org \
    --to=tipbot@zytor.com \
    --cc=acme@redhat.com \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=bsingharora@gmail.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tip-commits@vger.kernel.org \
    --cc=mhiramat@kernel.org \
    --cc=mingo@kernel.org \
    --cc=naveen.n.rao@linux.vnet.ibm.com \
    --cc=peterz@infradead.org \
    --cc=ravi.bangoria@linux.vnet.ibm.com \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.