linux/tools/perf/util/trace_augment.h

#ifndef TRACE_AUGMENT_H
#define TRACE_AUGMENT_H

#define TRACE_AUG_MAX_BUF 32 /* for buffer augmentation in perf trace */

#endif
perf trace: Pretty print buffer data Define TRACE_AUG_MAX_BUF in trace_augment.h data, which is the maximum buffer size we can augment. BPF will include this header too. Print buffer in a way that's different than just printing a string, we print all the control characters in \digits (such as \0 for null, and \10 for newline, LF). For character that has a bigger value than 127, we print the digits instead of the character itself as well. Committer notes: Simplified the buffer scnprintf to avoid using multiple buffers as discussed in the patch review thread. We can't really all 'buf' args to SCA_BUF as we're collecting so far just on the sys_enter path, so we would be printing the previous 'read' arg buffer contents, not what the kernel puts there. So instead of: static int syscall_fmt__cmp(const void name, const void fmtp) @@ -1987,8 +1989,6 @@ syscall_arg_fmt__init_array(struct syscall_arg_fmt arg, struct tep_format_field - else if (strstr(field->type, "char ") && strstr(field->name, "buf")) - arg->scnprintf = SCA_BUF; Do: static const struct syscall_fmt syscall_fmts[] = { + { .name = "write", .errpid = true, + .arg = { [1] = { .scnprintf = SCA_BUF /* buf */, from_user = true, }, }, }, Signed-off-by: Howard Chu <howardchu95@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240815013626.935097-8-howardchu95@gmail.com Link: https://lore.kernel.org/r/20240824163322.60796-6-howardchu95@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> 2024-08-25 00:33:19 +08:00			`#ifndef TRACE_AUGMENT_H`
			`#define TRACE_AUGMENT_H`

			`#define TRACE_AUG_MAX_BUF 32 /* for buffer augmentation in perf trace */`

			`#endif`