init: loosen serialize_overlap restrictions

When io_submit_mode=offload, allow overlap checking including for jobs
where no data is being changed and when the iodepth is one. These cases
can occur when checking for overlap across different jobs.

diff --git a/init.c b/init.c
index 1eddc6f20721a77db3e3ac0656455637f548cf48..a2b70c4acb4ba51a7916eda28f90bbcf3cdb10a9 100644 (file)
--- a/init.c
+++ b/init.c
@@ -744,19 +744,12 @@ static int fixup_options(struct thread_data *td)
        /*
         * There's no need to check for in-flight overlapping IOs if the job
         * isn't changing data or the maximum iodepth is guaranteed to be 1
+        * when we are not in offload mode
         */
        if (o->serialize_overlap && !(td->flags & TD_F_READ_IOLOG) &&
-           (!(td_write(td) || td_trim(td)) || o->iodepth == 1))
+           (!(td_write(td) || td_trim(td)) || o->iodepth == 1) &&
+           o->io_submit_mode != IO_MODE_OFFLOAD)
                o->serialize_overlap = 0;
-       /*
-        * Currently can't check for overlaps in offload mode
-        */
-       if (o->serialize_overlap && o->io_submit_mode == IO_MODE_OFFLOAD) {
-               log_err("fio: checking for in-flight overlaps when the "
-                       "io_submit_mode is offload is not supported\n");
-               o->serialize_overlap = 0;
-               ret |= warnings_fatal;
-       }
 
        if (o->nr_files > td->files_index)
                o->nr_files = td->files_index;