io_uring_submit: note specifics on return value for SQPOLL
Added the following behavior of io_uring_submit to the man page. When
used with SQ_POLL and in the success case, the return value may not
indicate the actual amount of successfully submitted submission queue
entries, as mentioned in issue 88
Signed-off-by: Constantin Pestka constantin.pestka@web.de
diff --git a/man/io_uring_submit.3 b/man/io_uring_submit.3
index f871b89..18a1532 100644
--- a/man/io_uring_submit.3
+++ b/man/io_uring_submit.3
@@ -26,7 +26,12 @@
.SH RETURN VALUE
On success
.BR io_uring_submit (3)
-returns the number of submitted submission queue entries. On failure it returns
+returns the number of submitted submission queue entries, if SQPOLL is not used.
+If SQPOLL is used, the return value may report a higher number of submitted
+entries than actually submitted. If the the user requires accurate information
+about how many submission queue entries have been successfully submitted, while
+using SQPOLL, the user must fall back to repeatedly submitting a single submission
+queue entry. On failure it returns
.BR -errno .
.SH NOTES
For any request that passes in data in a struct, that data must remain
