linux-kernel - [PATCH v1 0/2] Try to avoid some qsorts

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Message-Id: <20240703172117.810918-1-irogers@google.com>
Date: Wed,  3 Jul 2024 10:21:15 -0700
From: Ian Rogers <irogers@...gle.com>
To: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, 
	Arnaldo Carvalho de Melo <acme@...nel.org>, Namhyung Kim <namhyung@...nel.org>, 
	Mark Rutland <mark.rutland@....com>, 
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>, Jiri Olsa <jolsa@...nel.org>, 
	Ian Rogers <irogers@...gle.com>, Adrian Hunter <adrian.hunter@...el.com>, 
	Kan Liang <kan.liang@...ux.intel.com>, Athira Rajeev <atrajeev@...ux.vnet.ibm.com>, 
	linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Steinar Gunderson <sesse@...gle.com>, Matt Fleming <matt@...dmodwrite.com>
Subject: [PATCH v1 0/2] Try to avoid some qsorts

Reference count checking doesn't work well with rbtree due to the need
for counts on each child and parent edge. As such the reference count
checking changes removed rbtree and replaced them with sorted
arrays. There have been instances where sorting has been shown to be a
regression:
https://lore.kernel.org/lkml/20240521165109.708593-1-irogers@google.com/

These patches address a further 2 cases in comm and dsos, avoiding a
sort when the array is already sorted at the cost of an O(n) memmove.

Ian Rogers (2):
  perf comm str: Avoid sort during insert
  perf dsos: When adding a dso into sorted dsos maintain the sort order

 tools/perf/util/comm.c | 29 ++++++++++++++++++-----------
 tools/perf/util/dsos.c | 26 +++++++++++++++++++++-----
 2 files changed, 39 insertions(+), 16 deletions(-)

-- 
2.45.2.803.g4e1b14247a-goog