From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Stancek Date: Thu, 29 Nov 2018 12:09:42 +0100 Subject: [LTP] [PATCH] fzsync: limit sampling time Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Fixes: #429 Sampling can take considerably longer time on single CPU and very slow systems. This patch limits sampling time to 1/2 of fuzzing runtime (0.25 of test time). If we don't have enough samples by that time, stop sampling and use stats we gathered so far. Signed-off-by: Jan Stancek --- include/tst_fuzzy_sync.h | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/include/tst_fuzzy_sync.h b/include/tst_fuzzy_sync.h index 03f69b78bc82..0ca292c141c3 100644 --- a/include/tst_fuzzy_sync.h +++ b/include/tst_fuzzy_sync.h @@ -162,6 +162,7 @@ struct tst_fzsync_pair { * * Defaults to 0.5 (~150 seconds with default timeout). */ + float max_sampling_p; float exec_time_p; /** Internal; The test time remaining on tst_fzsync_pair_reset() */ float exec_time_start; @@ -199,6 +200,7 @@ static void tst_fzsync_pair_init(struct tst_fzsync_pair *pair) CHK(avg_alpha, 0, 1, 0.25); CHK(min_samples, 20, INT_MAX, 1024); CHK(max_dev_ratio, 0, 1, 0.1); + CHK(max_sampling_p, 0, 1, 0.25); CHK(exec_time_p, 0, 1, 0.5); CHK(exec_loops, 20, INT_MAX, 3000000); } @@ -582,9 +584,18 @@ static inline void tst_fzsync_wait_b(struct tst_fzsync_pair *pair) static inline int tst_fzsync_run_a(struct tst_fzsync_pair *pair) { int exit = 0; + float rem_p = 1 - tst_timeout_remaining() / pair->exec_time_start; + + /* Limit amount of time spent on sampling */ + if ((pair->max_sampling_p < rem_p) + && (pair->sampling > 0)) { + tst_res(TINFO, "stopping sampling at %d samples", + pair->sampling); + pair->sampling = 0; + tst_fzsync_pair_info(pair); + } - if (pair->exec_time_p - < 1 - tst_timeout_remaining() / pair->exec_time_start) { + if (pair->exec_time_p < rem_p) { tst_res(TINFO, "Exceeded execution time, requesting exit"); exit = 1; -- 1.8.3.1