Re: [PATCH 1/3] perf jvmti: Fix jitdump for methods without debug info

From: Ian Rogers
Date: Thu May 14 2020 - 18:07:14 EST


On Sun, Apr 26, 2020 at 11:16 PM Nick Gasson <nick.gasson@xxxxxxx> wrote:
>
> If a Java class is compiled with -g:none to omit debug information, the
> JVMTI plugin won't write jitdump entries for any method in this class
> and prints a lot of errors like:
>
> java: GetSourceFileName failed with JVMTI_ERROR_ABSENT_INFORMATION
>
> The call to GetSourceFileName is used to derive the file name `fn`, but
> this value is not actually used since commit ca58d7e64bdf ("perf jvmti:
> Generate correct debug information for inlined code") which moved the
> file name lookup into fill_source_filenames(). So the call to
> GetSourceFileName and related code can be safely removed.
>
> Signed-off-by: Nick Gasson <nick.gasson@xxxxxxx>

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
Tested-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks!
Ian

> ---
> tools/perf/jvmti/libjvmti.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/tools/perf/jvmti/libjvmti.c b/tools/perf/jvmti/libjvmti.c
> index c441a34cb1c0..50ef524b5cd4 100644
> --- a/tools/perf/jvmti/libjvmti.c
> +++ b/tools/perf/jvmti/libjvmti.c
> @@ -246,8 +246,6 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
> char *class_sign = NULL;
> char *func_name = NULL;
> char *func_sign = NULL;
> - char *file_name = NULL;
> - char fn[PATH_MAX];
> uint64_t addr = (uint64_t)(uintptr_t)code_addr;
> jvmtiError ret;
> int nr_lines = 0; /* in line_tab[] */
> @@ -282,12 +280,6 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
> }
> }
>
> - ret = (*jvmti)->GetSourceFileName(jvmti, decl_class, &file_name);
> - if (ret != JVMTI_ERROR_NONE) {
> - print_error(jvmti, "GetSourceFileName", ret);
> - goto error;
> - }
> -
> ret = (*jvmti)->GetClassSignature(jvmti, decl_class,
> &class_sign, NULL);
> if (ret != JVMTI_ERROR_NONE) {
> @@ -302,8 +294,6 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
> goto error;
> }
>
> - copy_class_filename(class_sign, file_name, fn, PATH_MAX);
> -
> /*
> * write source line info record if we have it
> */
> @@ -323,7 +313,6 @@ compiled_method_load_cb(jvmtiEnv *jvmti,
> (*jvmti)->Deallocate(jvmti, (unsigned char *)func_name);
> (*jvmti)->Deallocate(jvmti, (unsigned char *)func_sign);
> (*jvmti)->Deallocate(jvmti, (unsigned char *)class_sign);
> - (*jvmti)->Deallocate(jvmti, (unsigned char *)file_name);
> free(line_tab);
> while (line_file_names && (nr_lines > 0)) {
> if (line_file_names[nr_lines - 1]) {
> --
> 2.26.1
>