ktest: Add BISECT_TRIES to bisect test

For those cases that it takes several tries to hit a bug, it would be
useful for ktest.pl to try a test multiple times before it considers
the test as a pass. To accomplish this, BISECT_TRIES ktest config
option has been added. It is default to one, as most of the time a
bisect only needs to try a test once. But the user can now up this
to make ktest run a given test multiple times. The first failure
that is detected will set a bisect bad. It only repeats on success.

Note, as with all race bugs, there's no guarantee that if it succeeds,
it is really a good bisect. But it helps in case the bug is somewhat
reliable.

You can set BISECT_TRIES to zero, and all tests will be considered
good, unless you also set BISECT_MANUAL.

Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2014-01-18 19:52:13 -05:00 committed by Steven Rostedt
parent c75d22d9c6
commit 961d9cacee
2 changed files with 36 additions and 2 deletions

View file

@ -41,6 +41,7 @@ my %default = (
"CLEAR_LOG" => 0,
"BISECT_MANUAL" => 0,
"BISECT_SKIP" => 1,
"BISECT_TRIES" => 1,
"MIN_CONFIG_TYPE" => "boot",
"SUCCESS_LINE" => "login:",
"DETECT_TRIPLE_FAULT" => 1,
@ -139,6 +140,7 @@ my $bisect_bad_commit = "";
my $reverse_bisect;
my $bisect_manual;
my $bisect_skip;
my $bisect_tries;
my $config_bisect_good;
my $bisect_ret_good;
my $bisect_ret_bad;
@ -276,6 +278,7 @@ my %option_map = (
"IGNORE_ERRORS" => \$ignore_errors,
"BISECT_MANUAL" => \$bisect_manual,
"BISECT_SKIP" => \$bisect_skip,
"BISECT_TRIES" => \$bisect_tries,
"CONFIG_BISECT_GOOD" => \$config_bisect_good,
"BISECT_RET_GOOD" => \$bisect_ret_good,
"BISECT_RET_BAD" => \$bisect_ret_bad,
@ -2584,12 +2587,29 @@ sub run_bisect {
$buildtype = "useconfig:$minconfig";
}
my $ret = run_bisect_test $type, $buildtype;
# If the user sets bisect_tries to less than 1, then no tries
# is a success.
my $ret = 1;
if ($bisect_manual) {
# Still let the user manually decide that though.
if ($bisect_tries < 1 && $bisect_manual) {
$ret = answer_bisect;
}
for (my $i = 0; $i < $bisect_tries; $i++) {
if ($bisect_tries > 1) {
my $t = $i + 1;
doprint("Running bisect trial $t of $bisect_tries:\n");
}
$ret = run_bisect_test $type, $buildtype;
if ($bisect_manual) {
$ret = answer_bisect;
}
last if (!$ret);
}
# Are we looking for where it worked, not failed?
if ($reverse_bisect && $ret >= 0) {
$ret = !$ret;

View file

@ -1028,6 +1028,20 @@
# BISECT_BAD with BISECT_CHECK = good or
# BISECT_CHECK = bad, respectively.
#
# BISECT_TRIES = 5 (optional, default 1)
#
# For those cases that it takes several tries to hit a bug,
# the BISECT_TRIES is useful. It is the number of times the
# test is ran before it says the kernel is good. The first failure
# will stop trying and mark the current SHA1 as bad.
#
# Note, as with all race bugs, there's no guarantee that if
# it succeeds, it is really a good bisect. But it helps in case
# the bug is some what reliable.
#
# You can set BISECT_TRIES to zero, and all tests will be considered
# good, unless you also set BISECT_MANUAL.
#
# BISECT_RET_GOOD = 0 (optional, default undefined)
#
# In case the specificed test returns something other than just