On Mon, Apr 15, 2019 at 06:36:13PM +0300, Alexey Budankov wrote: > > When dwarf stacks are collected jointly with user specified register > set using --user-regs option like below the full register context is > still captured on a sample: > > $ perf record -g --call-graph dwarf,1024 --user-regs=IP,SP,BP -- > matrix.gcc.g.O3 > > 188143843893585 0x6b48 [0x4f8]: PERF_RECORD_SAMPLE(IP, 0x4002): > 23828/23828: 0x401236 period: 1363819 addr: 0x7ffedbdd51ac > ... FP chain: nr:0 > ... user regs: mask 0xff0fff ABI 64-bit > .... AX 0x53b > .... BX 0x7ffedbdd3cc0 > .... CX 0xffffffff > .... DX 0x33d3a > .... SI 0x7f09b74c38d0 > .... DI 0x0 > .... BP 0x401260 > .... SP 0x7ffedbdd3cc0 > .... IP 0x401236 > .... FLAGS 0x20a > .... CS 0x33 > .... SS 0x2b > .... R8 0x7f09b74c3800 > .... R9 0x7f09b74c2da0 > .... R10 0xfffffffffffff3ce > .... R11 0x246 > .... R12 0x401070 > .... R13 0x7ffedbdd5db0 > .... R14 0x0 > .... R15 0x0 > ... ustack: size 1024, offset 0xe0 > . data_src: 0x5080021 > ... thread: stack_test2.g.O:23828 > ...... dso: /root/abudanko/stacks/stack_test2.g.O3 > > After applying the change suggested in the patch the sample data contain > only user specified register values: > > $ perf record -g --call-graph dwarf,1024 --user-regs=IP,SP,BP -- > matrix.gcc.g.03 > > 188368474305373 0x5e40 [0x470]: PERF_RECORD_SAMPLE(IP, 0x4002): > 23839/23839: 0x401236 period: 1260507 addr: 0x7ffd3d85e96c > ... FP chain: nr:0 > ... user regs: mask 0x1c0 ABI 64-bit > .... BP 0x401260 > .... SP 0x7ffd3d85cc20 > .... IP 0x401236 > ... ustack: size 1024, offset 0x58 > . data_src: 0x5080021 > ... thread: stack_test2.g.O:23839 > ...... dso: /root/abudanko/stacks/stack_test2.g.O3 > > Signed-off-by: Alexey Budankov <[email protected]>
Acked-by: Jiri Olsa <[email protected]> thanks, jirka > --- > tools/perf/util/evsel.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 84cfb9fe2fc6..29a223b4c699 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -702,7 +702,8 @@ static void __perf_evsel__config_callchain(struct > perf_evsel *evsel, > if (!function) { > perf_evsel__set_sample_bit(evsel, REGS_USER); > perf_evsel__set_sample_bit(evsel, STACK_USER); > - attr->sample_regs_user |= PERF_REGS_MASK; > + if (!opts->sample_user_regs) > + attr->sample_regs_user |= PERF_REGS_MASK; > attr->sample_stack_user = param->dump_size; > attr->exclude_callchain_user = 1; > } else { > -- > 2.20.1 >
