Messages in this thread | | | Date | Mon, 24 Feb 2020 13:35:26 +0100 | From | Jiri Olsa <> | Subject | Re: [PATCH v3 2/2] Support interactive annotation of code without symbols |
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On Mon, Feb 24, 2020 at 10:22:25AM +0800, 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. > > v3: > --- > Keep just the ANNOTATION_DUMMY_LEN, and remove the > opts->annotate_dummy_len since it's the "maybe in future > we will provide" feature. > > v2: > --- > Fix a crash issue when annotating an address in "unknown" object. > > The steps to reproduce this issue: > > perf record -e cycles:u ls > perf report > > 75.29% ls ld-2.27.so [.] do_lookup_x > 23.64% ls ld-2.27.so [.] __GI___tunables_init > 1.04% ls [unknown] [k] 0xffffffff85c01210 > 0.03% ls ld-2.27.so [.] _start > > When annotating 0xffffffff85c01210, the crash happens. > > v2 adds checking for ms->map in add_annotate_opt(). If the object is > "unknown", ms->map is NULL. > > Signed-off-by: Jin Yao <yao.jin@linux.intel.com> > --- > tools/perf/ui/browsers/hists.c | 43 +++++++++++++++++++++++++++++----- > tools/perf/util/annotate.h | 1 + > 2 files changed, 38 insertions(+), 6 deletions(-) > > diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c > index f36dee499320..2f07680559c4 100644 > --- a/tools/perf/ui/browsers/hists.c > +++ b/tools/perf/ui/browsers/hists.c > @@ -2465,13 +2465,41 @@ do_annotate(struct hist_browser *browser, struct popup_action *act) > return 0; > } > > +static struct symbol *new_annotate_sym(u64 addr, struct map *map) > +{ > + struct symbol *sym; > + struct annotated_source *src; > + char name[64]; > + > + snprintf(name, sizeof(name), "%-#.*lx", BITS_PER_LONG / 4, addr); > + > + sym = symbol__new(addr, ANNOTATION_DUMMY_LEN, 0, 0, name); > + if (sym) { > + src = symbol__hists(sym, 1); > + if (!src) { > + symbol__delete(sym); > + return NULL; > + }
hi, I like the patchset:
Acked-by: Jiri Olsa <jolsa@redhat.com>
could you please also check if we can do this earlier, so the dummy symbol is actualy collecting all the hits?
like within the symbol__inc_addr_samples function, but I mght be missing something..
thanks, jirka
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