Commits
Ravi Bangoria committed bec60e50af8
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>