On Wed, Nov 18, 2015 at 12:13:08PM +0800, Wangnan (F) wrote: SNIP
> 3.38% a.out a.out [.] funcc > | > ---funcc > | > |--2.70%-- funcb > | funca > | main > | __libc_start_main > | _start > | > --0.68%-- 0 > > > I'm not sure whether we can regard this behavior changing as a bugfix? I > think > there may be some reason the original code explicitly avoid creating an '0' > entry. > > Then I tried to find why perf can't get call frame on my case, and > I guess there's something wrong whe dealing with 'call' command, because > the instruction on it I can't get callchain from libunwind is a 'callq': > > ... > 4005bf: be 00 00 00 00 mov $0x0,%esi > 4005c4: 48 89 c7 mov %rax,%rdi > 4005c7: e8 74 fe ff ff callq 400440 <gettimeofday@plt> > us2 = tv2.tv_sec * 1000000 + tv2.tv_usec; > 4005cc: 48 8b 04 24 mov (%rsp),%rax > ... > > But this is another problem, we can discuss it in a new thread. so the problem is you dont see the gettimeofday call at the end? could you share the test code? thanks, jirka -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/