From 70df6a7311186a7ab0b19f481dee4ca540a73837 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Mon, 1 Apr 2019 12:43:09 -0400 Subject: [PATCH] tools lib traceevent: Add more debugging to see various internal ring buffer entries When trace-cmd report --debug is set, show the internal ring buffer entries like time-extends and padding. This requires adding new kbuffer API to retrieve these items. Signed-off-by: Steven Rostedt (VMware) Cc: Andrew Morton Cc: Jiri Olsa Cc: Namhyung Kim Cc: Tzvetomir Stoyanov Link: http://lkml.kernel.org/r/20190401164343.257591565@goodmis.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/traceevent/kbuffer-parse.c | 49 ++++++++++++++++++++++++++++ tools/lib/traceevent/kbuffer.h | 13 ++++++++ 2 files changed, 62 insertions(+) diff --git a/tools/lib/traceevent/kbuffer-parse.c b/tools/lib/traceevent/kbuffer-parse.c index af2a1f3b7424..b887e7437d67 100644 --- a/tools/lib/traceevent/kbuffer-parse.c +++ b/tools/lib/traceevent/kbuffer-parse.c @@ -727,3 +727,52 @@ int kbuffer_start_of_data(struct kbuffer *kbuf) { return kbuf->start; } + +/** + * kbuffer_raw_get - get raw buffer info + * @kbuf: The kbuffer + * @subbuf: Start of mapped subbuffer + * @info: Info descriptor to fill in + * + * For debugging. This can return internals of the ring buffer. + * Expects to have info->next set to what it will read. + * The type, length and timestamp delta will be filled in, and + * @info->next will be updated to the next element. + * The @subbuf is used to know if the info is passed the end of + * data and NULL will be returned if it is. + */ +struct kbuffer_raw_info * +kbuffer_raw_get(struct kbuffer *kbuf, void *subbuf, struct kbuffer_raw_info *info) +{ + unsigned long long flags; + unsigned long long delta; + unsigned int type_len; + unsigned int size; + int start; + int length; + void *ptr = info->next; + + if (!kbuf || !subbuf) + return NULL; + + if (kbuf->flags & KBUFFER_FL_LONG_8) + start = 16; + else + start = 12; + + flags = read_long(kbuf, subbuf + 8); + size = (unsigned int)flags & COMMIT_MASK; + + if (ptr < subbuf || ptr >= subbuf + start + size) + return NULL; + + type_len = translate_data(kbuf, ptr, &ptr, &delta, &length); + + info->next = ptr + length; + + info->type = type_len; + info->delta = delta; + info->length = length; + + return info; +} diff --git a/tools/lib/traceevent/kbuffer.h b/tools/lib/traceevent/kbuffer.h index 03dce757553f..ed4d697fc137 100644 --- a/tools/lib/traceevent/kbuffer.h +++ b/tools/lib/traceevent/kbuffer.h @@ -65,4 +65,17 @@ int kbuffer_subbuffer_size(struct kbuffer *kbuf); void kbuffer_set_old_format(struct kbuffer *kbuf); int kbuffer_start_of_data(struct kbuffer *kbuf); +/* Debugging */ + +struct kbuffer_raw_info { + int type; + int length; + unsigned long long delta; + void *next; +}; + +/* Read raw data */ +struct kbuffer_raw_info *kbuffer_raw_get(struct kbuffer *kbuf, void *subbuf, + struct kbuffer_raw_info *info); + #endif /* _K_BUFFER_H */ -- 2.30.2