Em Thu, Mar 19, 2015 at 06:02:04PM +0800, He Kuang escreveu: > Perf tries to find probe function addresses from map when debuginfo > could not be found. > > To the first added function, the value of ref_reloc_sym was set in > maps__set_kallsyms_ref_reloc_sym() and can be obtained from > host_machine->kmaps->maps. After that, new maps are added to > host_machine->kmaps->maps in dso__load_kcore(), all these new added maps > do not have a valid ref_reloc_sym. > > When adding a second function, get_target_map() may get a map without > valid ref_reloc_sym, and raise the error "Relocated base symbol is not > found". > > Fix this by getting ref_reloc_sym from machine->vmlinux_maps.
Can't this be solved by using the kernel_get_ref_reloc_sym(void) static function in this same file? - Arnaldo > This problem can be reproduced as following: > > $ perf probe --add='sys_write' --add='sys_open' > Relocated base symbol is not found! > Error: Failed to add events. > > After this patch: > > $ perf probe --add='sys_write' --add='sys_open' > Added new event: > probe:sys_write (on sys_write) > > You can now use it in all perf tools, such as: > > perf record -e probe:sys_write -aR sleep 1 > > Added new event: > probe:sys_open (on sys_open) > > You can now use it in all perf tools, such as: > > perf record -e probe:sys_open -aR sleep 1 > > Signed-off-by: He Kuang <[email protected]> > --- > tools/perf/util/probe-event.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index c5e1338..75d41ee 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -2540,7 +2540,19 @@ static int find_probe_trace_events_from_map(struct > perf_probe_event *pev, > } > > if (!pev->uprobes && !pp->retprobe) { > - kmap = map__kmap(map); > + struct machine *machine; > + struct map *vmlinux_map = NULL; > + > + if (map->groups && map->groups->machine) { > + machine = map->groups->machine; > + vmlinux_map = machine->vmlinux_maps[MAP__FUNCTION]; > + } > + > + if (vmlinux_map) > + kmap = map__kmap(vmlinux_map); > + else > + kmap = map__kmap(map); > + > reloc_sym = kmap->ref_reloc_sym; > if (!reloc_sym) { > pr_warning("Relocated base symbol is not found!\n"); > -- > 2.3.3.220.g9ab698f -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
