[tip:perf/core] perf trace: Consume the augmented_raw_syscalls payload

From: tip-bot for Arnaldo Carvalho de Melo
Date: Mon Jun 17 2019 - 15:21:16 EST

Commit-ID: 8195168e877948bb9a943ce11ad3e6ee71014bd5
Gitweb: https://git.kernel.org/tip/8195168e877948bb9a943ce11ad3e6ee71014bd5
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Wed, 5 Jun 2019 10:34:47 -0300
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 5 Jun 2019 10:52:19 -0300

perf trace: Consume the augmented_raw_syscalls payload

To support the SCA_FILENAME beautifier in more than one syscall arg, as
needed for syscalls such as the rename* family, we need to, after
processing one such arg, bump the augmented pointers so that the next
augmented arg don't reuse data for the previous augmented arguments.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Luis ClÃudio GonÃalves <lclaudio@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-4e4cmzyjxb3wkonfo1x9a27y@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
tools/perf/builtin-trace.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 19f22127f02e..905e57c336b0 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1233,8 +1233,17 @@ static void thread__set_filename_pos(struct thread *thread, const char *bf,
static size_t syscall_arg__scnprintf_augmented_string(struct syscall_arg *arg, char *bf, size_t size)
struct augmented_arg *augmented_arg = arg->augmented.args;
+ size_t printed = scnprintf(bf, size, "\"%.*s\"", augmented_arg->size, augmented_arg->value);
+ /*
+ * So that the next arg with a payload can consume its augmented arg, i.e. for rename* syscalls
+ * we would have two strings, each prefixed by its size.
+ */
+ int consumed = sizeof(*augmented_arg) + augmented_arg->size;

- return scnprintf(bf, size, "\"%.*s\"", augmented_arg->size, augmented_arg->value);
+ arg->augmented.args += consumed;
+ arg->augmented.size -= consumed;
+ return printed;

static size_t syscall_arg__scnprintf_filename(char *bf, size_t size,