perf scripts python: Implement add sample function and thread processing

The intern_stack function is responsible for retrieving
or creating a stack_id based on the provided frame_id and prefix_id.
It first generates a key using the frame_id and prefix_id values.
If the stack corresponding to the key is found in the stackMap,
it is returned. Otherwise, a new stack is created by appending
the prefix_id and frame_id to the stackTable. The key
and the index of the newly created stack are added to the
stackMap for future reference.

The _intern_frame function is responsible for retrieving or
creating a frame_id based on the provided frame string. If the frame_id
corresponding to the frameString is found in the frameMap, it is
returned. Otherwise, a new frame is created by appending relevant
information to the frameTable and adding the frameString to the string_id
through _intern_string.

The _intern_string function will gets a matching string, or saves the new
string and returns a String ID.

Signed-off-by: Anup Sharma <anupnewsmail@gmail.com>
Link: https://lore.kernel.org/r/4442f4b1ab4c7317cf940560a3a285fcdfbeeb08.1689961706.git.anupnewsmail@gmail.com


Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>