kernel-packages team mailing list archive

[bugproxy <bugproxy@xxxxxxxxxx>]

------- Comment From naveen.n.rao@xxxxxxxxxx 2015-09-11 08:59 EDT-------
Canonical,
Any update on this?

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1485528

Title:
  perf probe: ppc64le/ABIv2 support

Status in linux package in Ubuntu:
  New

Bug description:
  Problem Description
  ========================
  perf probe does not work properly on ppc64le

  ---uname output---
  Linux ubuntu1504 3.19.0-22-generic #22-Ubuntu SMP Tue Jun 16 17:15:17 UTC 2015 ppc64le ppc64le ppc64le GNU/Linux
   
  Machine Type = POWER 

  Steps to Reproduce
  ========================
   'perf probe do_fork' adds the probe, but is not able to capture events on 'perf record -e probe:do_fork -a'. This is because ppc64le ABIv2 uses local entry points at an offset from the global entry point where the probe is currently being placed.

  These issues have been fixed upstream with the below patch series:
  - http://thread.gmane.org/gmane.linux.kernel/1939488
  - http://thread.gmane.org/gmane.linux.kernel/1941352

  == Comment: #1 - Naveen N. Rao <naveen.n.rao@xxxxxxxxxx> - 2015-07-01 07:03:19 ==
  I have backported the patches relevant for ppc64le and I am attaching them here. These fixes are needed for 15.04, 14.04.03 and 15.10 (depending on the kernel it gets based on). For reference, upstream commits in -tip for reference:
  - d4c537e6bf860c12262cb936eef663180d7a3d45: perf probe: Ignore tail calls to probed functions
  - 3099c026002e97b8c173d9d0bbdfc39257d14402: perf probe: Improve detection of file/function name in the probe pattern
  - 7b6ff0bdbf4f7f429c2116cca92a6d171217449e: perf probe ppc64le: Fixup function entry if using kallsyms lookup
  - d5c2e2c17ae1d630ddbceb53a264f24cc99703a4: perf probe ppc64le: Prefer symbol table lookup over DWARF
  - c50fc0a43e33a6c3257c5cbb954cd747d7b9a680: perf probe ppc64le: Fix ppc64 ABIv2 symbol decoding
  - 031b84c407c3153ffbcb4f8f832edf48af988719: perf probe ppc: Enable matching against dot symbols automatically
  - fb6d59423115b10125f5db6acb8471f6f0af4ad7: perf probe ppc: Use the right prefix when ignoring SyS symbols on ppc
  - d2332098331fffe9358b50cebc8954ecd6560448: perf probe ppc: Fix symbol fixup issues due to ELF type

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1485528/+subscriptions