[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1370941728-15456-1-git-send-email-juri.lelli@gmail.com>
Date: Tue, 11 Jun 2013 11:08:45 +0200
From: Juri Lelli <juri.lelli@...il.com>
To: rostedt@...dmis.org, fweisbec@...il.com, mingo@...hat.com
Cc: linux-kernel@...r.kernel.org, juri.lelli@...il.com
Subject: [PATCH 0/3] ftrace: fix stddev calculation and add a test for it
While profiling kernel functions via ftrace I noticed values of s^2 that
seemed odd. I implemented a test to verify correctness of averages and
s^2 calculations and proved the latter to be wrong. Then I fixed them up.
The first patch refactors function_stat_show() code a bit in order to be
able to implement the test (second patch). Third patch fixes up s^2
calculation (applying Welford's method).
Juri Lelli (3):
ftrace: refactor basis statistics calculation code
ftrace: test basic statistics calculation
ftrace: fix stddev calculation
kernel/trace/ftrace.c | 50 ++++++++++++++--------------
kernel/trace/trace.h | 16 +++++++++
kernel/trace/trace_selftest.c | 72 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 114 insertions(+), 24 deletions(-)
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists