lkml.org 
[lkml]   [2020]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v3 2/2] Support interactive annotation of code without symbols
    On Mon, Feb 24, 2020 at 06:55:12PM +0530, Ravi Bangoria wrote:
    > Hi Jin,
    >
    > On 2/24/20 7:52 AM, Jin Yao wrote:
    > > For perf report on stripped binaries it is currently impossible to do
    > > annotation. The annotation state is all tied to symbols, but there are
    > > either no symbols, or symbols are not covering all the code.
    > >
    > > We should support the annotation functionality even without symbols.
    > >
    > > This patch fakes a symbol and the symbol name is the string of address.
    > > After that, we just follow current annotation working flow.
    > >
    > > For example,
    > >
    > > 1. perf report
    > >
    > > Overhead Command Shared Object Symbol
    > > 20.67% div libc-2.27.so [.] __random_r
    > > 17.29% div libc-2.27.so [.] __random
    > > 10.59% div div [.] 0x0000000000000628
    > > 9.25% div div [.] 0x0000000000000612
    > > 6.11% div div [.] 0x0000000000000645
    > >
    > > 2. Select the line of "10.59% div div [.] 0x0000000000000628" and ENTER.
    > >
    > > Annotate 0x0000000000000628
    > > Zoom into div thread
    > > Zoom into div DSO (use the 'k' hotkey to zoom directly into the kernel)
    > > Browse map details
    > > Run scripts for samples of symbol [0x0000000000000628]
    > > Run scripts for all samples
    > > Switch to another data file in PWD
    > > Exit
    > >
    > > 3. Select the "Annotate 0x0000000000000628" and ENTER.
    > >
    > > Percent│
    > > │
    > > │
    > > │ Disassembly of section .text:
    > > │
    > > │ 0000000000000628 <.text+0x68>:
    > > │ divsd %xmm4,%xmm0
    > > │ divsd %xmm3,%xmm1
    > > │ movsd (%rsp),%xmm2
    > > │ addsd %xmm1,%xmm0
    > > │ addsd %xmm2,%xmm0
    > > │ movsd %xmm0,(%rsp)
    > >
    > > Now we can see the dump of object starting from 0x628.
    >
    > If I press 'a' on address, it's not annotating. But if I annotate
    > by pressing enter, like you explained, it works. Is it intentional?

    I saw that too, but I thought it's unrelated issue,
    because we played with that just recently

    if you go through the 'enter' way and back, then the
    next time 'a' works ;-)

    jirka

    \
     
     \ /
      Last update: 2020-02-24 14:52    [W:3.851 / U:0.180 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site