[PATCH qemu 1/1] Add IOURING_SETUP_SINGLE_ISSUER flag to improve iouring performance

[~h0lyalg0rithm]

From: Suraj Shirvankar <surajshirvan...@gmail.com>

Signed-off-by: Suraj Shirvankar <surajshirvan...@gmail.com>
---
 util/fdmon-io_uring.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/util/fdmon-io_uring.c b/util/fdmon-io_uring.c
index b0d68bdc44..235837abcb 100644
--- a/util/fdmon-io_uring.c
+++ b/util/fdmon-io_uring.c
@@ -324,8 +324,14 @@ static const FDMonOps fdmon_io_uring_ops = {
 bool fdmon_io_uring_setup(AioContext *ctx)
 {
     int ret;
+    unsigned int flags = 0;
 
-    ret = io_uring_queue_init(FDMON_IO_URING_ENTRIES, &ctx->fdmon_io_uring, 0);
+    /* This improves performance but can be skipped on old hosts */
+#ifdef IORING_SETUP_SINGLE_ISSUER
+    flags |= IORING_SETUP_SINGLE_ISSUER
+#endif
+
+    ret = io_uring_queue_init(FDMON_IO_URING_ENTRIES, &ctx->fdmon_io_uring, 
flags);
     if (ret != 0) {
         return false;
     }
-- 
2.45.3