[S] Change in libosmocore[master]: Remove old empty io_uring

jolly has uploaded this change for review. ( https://gerrit.osmocom.org/c/libosmocore/+/40855?usp=email ) Change subject: Remove old empty io_uring ...................................................................... Remove old empty io_uring A previous patch creates a new io_uring, if it becomes too small to store all SQEs. When all SQEs of the old ring are completed, the old ring will be destroyed. A counter is incremented whenever an SQE is submitted to an io_uring. The counter is decrements whenever a CQE is received and handled. This counter will determine when a ring is empty and can be destroyed. Related: OS#6705 Change-Id: Id2d2a0400ad442198c684ea0ead4eaeaead4c53d --- M src/core/osmo_io_uring.c 1 file changed, 27 insertions(+), 4 deletions(-) git pull ssh://gerrit.osmocom.org:29418/libosmocore refs/changes/55/40855/1 diff --git a/src/core/osmo_io_uring.c b/src/core/osmo_io_uring.c index 1a817dd..a867968 100644 --- a/src/core/osmo_io_uring.c +++ b/src/core/osmo_io_uring.c @@ -65,7 +65,7 @@ bool g_io_uring_batch = false; bool g_io_uring_submit_needed = false; -static unsigned int g_io_uring_size = IOFD_URING_INITIAL_SIZE; +static int g_io_uring_size = IOFD_URING_INITIAL_SIZE; static int g_io_uring_read_sqes = 1; @@ -73,6 +73,7 @@ struct osmo_fd event_ofd; struct io_uring ring; struct llist_head cancel_queue; + unsigned int in_flight; }; static __thread struct osmo_io_uring *g_ring = NULL; @@ -167,13 +168,27 @@ } } +static void osmo_iofd_uring_exit(struct osmo_io_uring *ring) +{ + LOGP(DLIO, LOGL_DEBUG, "Old empty io_uring will be destroyed."); + + io_uring_queue_exit(&ring->ring); + + osmo_fd_unregister(&ring->event_ofd); + close(ring->event_ofd.fd); + + talloc_free(ring); +} + static struct io_uring_sqe *iofd_uring_get_sqe(bool current_ring) { struct io_uring_sqe *sqe; sqe = io_uring_get_sqe(&g_ring->ring); - if (sqe) + if (sqe) { + g_ring->in_flight++; return sqe; + } if (g_io_uring_size < IOFD_URING_MAXIMUM_SIZE) { LOGP(DLIO, LOGL_NOTICE, "io_uring too small to handle all SQEs with its current size of %d. " @@ -197,6 +212,7 @@ sqe = io_uring_get_sqe(&g_ring->ring); OSMO_ASSERT(sqe); + g_ring->in_flight++; return sqe; } @@ -424,6 +440,7 @@ struct osmo_io_uring *orig_ring = container_of(ring, struct osmo_io_uring, ring); while (io_uring_peek_cqe(ring, &cqe) == 0) { + orig_ring->in_flight--; msghdr = io_uring_cqe_get_data(cqe); if (!msghdr) { @@ -448,13 +465,18 @@ } /* If there are unsubmitted cancel SQEs, try to queue them now. */ - if (OSMO_LIKELY(llist_empty(&orig_ring->cancel_queue))) + if (OSMO_LIKELY(llist_empty(&orig_ring->cancel_queue))) { + /* Old ring is empty, remove it. */ + if (OSMO_UNLIKELY(orig_ring != g_ring && orig_ring->in_flight == 0)) + osmo_iofd_uring_exit(orig_ring); return; + } llist_for_each_entry_safe(msghdr, msghdr2, &orig_ring->cancel_queue, list) { struct io_uring_sqe *sqe; sqe = io_uring_get_sqe(&orig_ring->ring); if (!sqe) break; + orig_ring->in_flight++; io_uring_sqe_set_data(sqe, NULL); LOGP(DLIO, LOGL_DEBUG, "Cancelling queued read/write\n"); io_uring_prep_cancel(sqe, msghdr, 0); @@ -462,7 +484,6 @@ msghdr->in_cancel_queue = false; } io_uring_submit(&orig_ring->ring); - } /*! will submit the next to-be-transmitted message for given iofd */ @@ -584,6 +605,7 @@ /* If the submission queue is full, use cancel queue. We cannot cancel SQEs on the new ring. */ sqe = io_uring_get_sqe(&ring->ring); if (sqe) { + ring->in_flight++; io_uring_sqe_set_data(sqe, NULL); LOGPIO(iofd, LOGL_DEBUG, "Cancelling read\n"); io_uring_prep_cancel(sqe, msghdr, 0); @@ -614,6 +636,7 @@ /* If the submission queue is full, use cancel queue. We cannot cancel SQEs on the new ring. */ sqe = io_uring_get_sqe(&ring->ring); if (sqe) { + ring->in_flight++; io_uring_sqe_set_data(sqe, NULL); LOGPIO(iofd, LOGL_DEBUG, "Cancelling write\n"); io_uring_prep_cancel(sqe, msghdr, 0); -- To view, visit https://gerrit.osmocom.org/c/libosmocore/+/40855?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings?usp=email Gerrit-MessageType: newchange Gerrit-Project: libosmocore Gerrit-Branch: master Gerrit-Change-Id: Id2d2a0400ad442198c684ea0ead4eaeaead4c53d Gerrit-Change-Number: 40855 Gerrit-PatchSet: 1 Gerrit-Owner: jolly &lt;andreas(a)eversberg.eu&gt;