From: aggieNick02 <nick@pcpartpicker.com>
Date: Tue, 15 Feb 2022 17:59:34 +0000 (-0600)
Subject: Fix :<nr> suffix with random read/write causing 0 initial offset
X-Git-Tag: fio-3.30~45^2
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=54833d02a6ac307a894ed4445db9fe25e530b518;p=fio.git

Fix :<nr> suffix with random read/write causing 0 initial offset

When using the :<nr> suffix with random reads or writes, the initial
offset would be set to 0 for the first nr-1 operations. This happened
because td->ddir_seq_nr was initialized to the specified option value,
when it needs to always be initialized to 1, so that the first call to
get_next_offset leads to choosing a new random offset for the first nr
operations.

Signed-off-by: Nick Neumann nick@pcpartpicker.com
---

diff --git a/init.c b/init.c
index 13935152..81c30f8c 100644
--- a/init.c
+++ b/init.c
@@ -1576,7 +1576,14 @@ static int add_job(struct thread_data *td, const char *jobname, int job_add_num,
 	td->ts.sig_figs = o->sig_figs;
 
 	init_thread_stat_min_vals(&td->ts);
-	td->ddir_seq_nr = o->ddir_seq_nr;
+
+	/*
+	 * td->>ddir_seq_nr needs to be initialized to 1, NOT o->ddir_seq_nr,
+	 * so that get_next_offset gets a new random offset the first time it
+	 * is called, instead of keeping an initial offset of 0 for the first
+	 * nr-1 calls
+	 */
+	td->ddir_seq_nr = 1;
 
 	if ((o->stonewall || o->new_group) && prev_group_jobs) {
 		prev_group_jobs = 0;