Re: [PATCH v3] Add a "-m" option to "perf buildid-list".
From: Arnaldo Carvalho de Melo
Date: Mon Jul 18 2022 - 10:51:20 EST
Em Fri, Jul 01, 2022 at 10:23:26AM +0200, Jiri Olsa escreveu:
> On Wed, Jun 29, 2022 at 02:36:32PM -0700, Blake Jones wrote:
> > This new option displays all of the information needed to do external
> > BuildID-based symbolization of kernel stack traces, such as those collected
> > by bpf_get_stackid(). For each kernel module plus the main kernel, it
> > displays the BuildID, the start and end virtual addresses of that module's
> > text range (rounded out to page boundaries), and the pathname of the
> > module.
> >
> > When run as a non-privileged user, the actual addresses of the modules'
> > text ranges are not available, so the tools displays "0, <text length>" for
> > kernel modules and "0, 0xffffffffffffffff" for the kernel itself.
> >
> > Sample output:
> >
> > root# perf buildid-list -m
> > cf6df852fd4da122d616153353cc8f560fd12fe0 ffffffffa5400000 ffffffffa6001e27 [kernel.kallsyms]
> > 1aa7209aa2acb067d66ed6cf7676d65066384d61 ffffffffc0087000 ffffffffc008b000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/sha512_generic.ko
> > 3857815b5bf0183697b68f8fe0ea06121644041e ffffffffc008c000 ffffffffc0098000 /lib/modules/5.15.15-1rodete2-amd64/kernel/arch/x86/crypto/sha512-ssse3.ko
> > 4081fde0bca2bc097cb3e9d1efcb836047d485f1 ffffffffc0099000 ffffffffc009f000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/acpi/button.ko
> > 1ef81ba4890552ea6b0314f9635fc43fc8cef568 ffffffffc00a4000 ffffffffc00aa000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/cryptd.ko
> > cc5c985506cb240d7d082b55ed260cbb851f983e ffffffffc00af000 ffffffffc00b6000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/i2c/busses/i2c-piix4.ko
> > [...]
> >
> > Signed-off-by: Blake Jones <blakejones@xxxxxxxxxx>
>
> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
To clarify, b4 found v3 and that was the one applied.
Thanks,
- Arnaldo
> thanks,
> jirka
>
> > ---
> > .../perf/Documentation/perf-buildid-list.txt | 4 ++
> > tools/perf/builtin-buildid-list.c | 38 ++++++++++++++++++-
> > tools/perf/util/machine.c | 15 ++++++++
> > tools/perf/util/machine.h | 5 +++
> > 4 files changed, 61 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/Documentation/perf-buildid-list.txt b/tools/perf/Documentation/perf-buildid-list.txt
> > index 25c52efcc7f0..e1e8fdbe06b9 100644
> > --- a/tools/perf/Documentation/perf-buildid-list.txt
> > +++ b/tools/perf/Documentation/perf-buildid-list.txt
> > @@ -33,6 +33,10 @@ OPTIONS
> > -k::
> > --kernel::
> > Show running kernel build id.
> > +-m::
> > +--kernel-maps::
> > + Show buildid, start/end text address, and path of running kernel and
> > + its modules.
> > -v::
> > --verbose::
> > Be more verbose.
> > diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
> > index cebadd632234..cffca6a536e9 100644
> > --- a/tools/perf/builtin-buildid-list.c
> > +++ b/tools/perf/builtin-buildid-list.c
> > @@ -12,6 +12,7 @@
> > #include "util/build-id.h"
> > #include "util/debug.h"
> > #include "util/dso.h"
> > +#include "util/map.h"
> > #include <subcmd/pager.h>
> > #include <subcmd/parse-options.h>
> > #include "util/session.h"
> > @@ -20,6 +21,34 @@
> > #include <errno.h>
> > #include <linux/err.h>
> >
> > +static int buildid__map_cb(struct map *map, void *arg __maybe_unused)
> > +{
> > + const struct dso *dso = map->dso;
> > + char bid_buf[SBUILD_ID_SIZE];
> > +
> > + memset(bid_buf, 0, sizeof(bid_buf));
> > + if (dso->has_build_id)
> > + build_id__sprintf(&dso->bid, bid_buf);
> > + printf("%s %16lx %16lx", bid_buf, map->start, map->end);
> > + if (dso->long_name != NULL) {
> > + printf(" %s", dso->long_name);
> > + } else if (dso->short_name != NULL) {
> > + printf(" %s", dso->short_name);
> > + }
> > + printf("\n");
> > +
> > + return 0;
> > +}
> > +
> > +static void buildid__show_kernel_maps(void)
> > +{
> > + struct machine *machine;
> > +
> > + machine = machine__new_host();
> > + machine__for_each_kernel_map(machine, buildid__map_cb, NULL);
> > + machine__delete(machine);
> > +}
> > +
> > static int sysfs__fprintf_build_id(FILE *fp)
> > {
> > char sbuild_id[SBUILD_ID_SIZE];
> > @@ -99,6 +128,7 @@ static int perf_session__list_build_ids(bool force, bool with_hits)
> > int cmd_buildid_list(int argc, const char **argv)
> > {
> > bool show_kernel = false;
> > + bool show_kernel_maps = false;
> > bool with_hits = false;
> > bool force = false;
> > const struct option options[] = {
> > @@ -106,6 +136,8 @@ int cmd_buildid_list(int argc, const char **argv)
> > OPT_STRING('i', "input", &input_name, "file", "input file name"),
> > OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
> > OPT_BOOLEAN('k', "kernel", &show_kernel, "Show current kernel build id"),
> > + OPT_BOOLEAN('m', "kernel-maps", &show_kernel_maps,
> > + "Show build id of current kernel + modules"),
> > OPT_INCR('v', "verbose", &verbose, "be more verbose"),
> > OPT_END()
> > };
> > @@ -117,8 +149,12 @@ int cmd_buildid_list(int argc, const char **argv)
> > argc = parse_options(argc, argv, options, buildid_list_usage, 0);
> > setup_pager();
> >
> > - if (show_kernel)
> > + if (show_kernel) {
> > return !(sysfs__fprintf_build_id(stdout) > 0);
> > + } else if (show_kernel_maps) {
> > + buildid__show_kernel_maps();
> > + return 0;
> > + }
> >
> > return perf_session__list_build_ids(force, with_hits);
> > }
> > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> > index 009061852808..16d225149b93 100644
> > --- a/tools/perf/util/machine.c
> > +++ b/tools/perf/util/machine.c
> > @@ -3327,3 +3327,18 @@ int machine__for_each_dso(struct machine *machine, machine__dso_t fn, void *priv
> > }
> > return err;
> > }
> > +
> > +int machine__for_each_kernel_map(struct machine *machine, machine__map_t fn, void *priv)
> > +{
> > + struct maps *maps = machine__kernel_maps(machine);
> > + struct map *map;
> > + int err = 0;
> > +
> > + for (map = maps__first(maps); map != NULL; map = map__next(map)) {
> > + err = fn(map, priv);
> > + if (err != 0) {
> > + break;
> > + }
> > + }
> > + return err;
> > +}
> > diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
> > index 5d7daf7cb7bc..e1476343cbb2 100644
> > --- a/tools/perf/util/machine.h
> > +++ b/tools/perf/util/machine.h
> > @@ -262,6 +262,11 @@ typedef int (*machine__dso_t)(struct dso *dso, struct machine *machine, void *pr
> >
> > int machine__for_each_dso(struct machine *machine, machine__dso_t fn,
> > void *priv);
> > +
> > +typedef int (*machine__map_t)(struct map *map, void *priv);
> > +int machine__for_each_kernel_map(struct machine *machine, machine__map_t fn,
> > + void *priv);
> > +
> > int machine__for_each_thread(struct machine *machine,
> > int (*fn)(struct thread *thread, void *p),
> > void *priv);
> >
> > base-commit: 1bcca2b1bd67f3c0e5c3a88ed16c6389f01a5b31
> > --
> > 2.37.0.rc0.161.g10f37bed90-goog
> >
--
- Arnaldo