263925bf84
Support data type annotation with new --data-type option. It internally
uses type sort key to collect sample histogram for the type and display
every members like below.
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
For simplicity it prints the number of samples per field for now.
But it should be easy to show the overhead percentage instead.
The number at the outer struct is a sum of the numbers of the inner
members. For example, struct cfs_rq got total 13 samples, and 2 came
from the load (struct load_weight) and 1 from h_nr_running. Similarly,
the struct load_weight got total 2 samples and they all came from the
weight field.
I've added two new flags in the symbol_conf for this. The
annotate_data_member is to get the members of the type. This is also
needed for perf report with typeoff sort key. The annotate_data_sample
is to update sample stats for each offset and used only in annotate.
Currently it only support stdio output mode, TUI support can be added
later.
Committer testing:
With the perf.data from the previous csets, a very simple, short
duration one:
# perf annotate --data-type
Annotate type: 'struct list_head' in [kernel.kallsyms] (1 samples):
============================================================================
samples offset size field
1 0 16 struct list_head {
0 0 8 struct list_head* next;
1 8 8 struct list_head* prev;
};
Annotate type: 'char' in [kernel.kallsyms] (1 samples):
============================================================================
samples offset size field
1 0 1 char ;
#
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-15-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
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