perf/core improvements and fixes:

Fixes:

- Do not show a bogus target address in 'perf annotate' for targetless powerpc
  jump instructions such as 'bctr' (Ravi Bangoria)

- tools/build fixes related to race conditions with the fixdep utility (Jiri Olsa)

- Fix building objtool with clang (Peter Foley)

Infrastructure:

- Support linking perf with clang and LLVM libraries, initially statically, but
  this limitation will be lifted and shared libraries, when available, will
  be preferred to the static build, that should, as with other features, be
  enabled explicitly (Wang Nan)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf annotate: Show raw form for jump instruction with indirect target

For jump instructions that does not include target address as direct operand,
show the original disassembled line for them. This is needed for certain
powerpc jump instructions that use target address in a register (such as bctr,
btar, ...).

Before:
     ld     r12,32088(r12)
     mtctr  r12
  v  bctr   ffffffffffffca2c
     std    r2,24(r1)
     addis  r12,r2,-1

After:
     ld     r12,32088(r12)
     mtctr  r12
  v  bctr
     std    r2,24(r1)
     addis  r12,r2,-1

Committer notes:

Testing it using a perf.data file and vmlinux for powerpc64,
cross-annotating it on a x86_64 workstation:

Before:

  .__bpf_prog_run  vmlinux.powerpc
         │        std    r10,512(r9)                      ▒
         │        lbz    r9,0(r31)                        ▒
         │        rldicr r9,r9,3,60                       ▒
         │        ldx    r9,r30,r9                        ▒
         │        mtctr  r9                               ▒
  100.00 │      ↓ bctr   3fffffffffe01510                 ▒
         │        lwa    r10,4(r31)                       ▒
         │        lwz    r9,0(r31)                        ▒
  <SNIP>
  Invalid jump offset: 3fffffffffe01510

After:

  .__bpf_prog_run  vmlinux.powerpc
         │        std    r10,512(r9)                      ▒
         │        lbz    r9,0(r31)                        ▒
         │        rldicr r9,r9,3,60                       ▒
         │        ldx    r9,r30,r9                        ▒
         │        mtctr  r9                               ▒
  100.00 │      ↓ bctr                                    ▒
         │        lwa    r10,4(r31)                       ▒
         │        lwz    r9,0(r31)                        ▒
  <SNIP>
  Invalid jump offset: 3fffffffffe01510

This, in turn, uncovers another problem with jumps without operands, the
ENTER/-> operation, to jump to the target, still continues using the bogus
target :-)

BTW, this was the file used for the above tests:

  [acme@jouet ravi_bangoria]$ perf report --header-only -i perf.data.f22vm.powerdev
  # ========
  # captured on: Thu Nov 24 12:40:38 2016
  # hostname : pdev-f22-qemu
  # os release : 4.4.10-200.fc22.ppc64
  # perf version : 4.9.rc1.g6298ce
  # arch : ppc64
  # nrcpus online : 48
  # nrcpus avail : 48
  # cpudesc : POWER7 (architected), altivec supported
  # cpuid : 74,513
  # total memory : 4158976 kB
  # cmdline : /home/ravi/Workspace/linux/tools/perf/perf record -a
  # event : name = cycles:ppp, , size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD, disabled = 1, inherit = 1, mmap = 1, c
  # HEADER_CPU_TOPOLOGY info available, use -I to display
  # HEADER_NUMA_TOPOLOGY info available, use -I to display
  # pmu mappings: cpu = 4, software = 1, tracepoint = 2, breakpoint = 5
  # missing features: HEADER_TRACING_DATA HEADER_BRANCH_STACK HEADER_GROUP_DESC HEADER_AUXTRACE HEADER_STAT HEADER_CACHE
  # ========
  #
  [acme@jouet ravi_bangoria]$

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chris Riyder <chris.ryder@arm.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1480953407-7605-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1 file changed