[PATCH] virtiofsd: Used glib "shared" thread pool

[Vivek Goyal <vgoyal@redhat.com>]

glib offers thread pools and it seems to support "exclusive" and "shared"
thread pools.

https://developer.gnome.org/glib/stable/glib-Thread-Pools.html#g-thread-pool-new

Currently we use "exlusive" thread pools but its performance seems to be
poor. I tried using "shared" thread pools and performance seems much
better. I posted performance results here.

https://www.redhat.com/archives/virtio-fs/2020-September/msg00080.html

So lets switch to shared thread pools. We can think of making it optional
once somebody can show in what cases exclusive thread pools offer better
results. For now, my simple performance tests across the board see
better results with shared thread pools.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: qemu/tools/virtiofsd/fuse_virtio.c
===================================================================
--- qemu.orig/tools/virtiofsd/fuse_virtio.c	2020-09-21 17:28:27.444438015 -0400
+++ qemu/tools/virtiofsd/fuse_virtio.c	2020-09-21 17:28:30.584568910 -0400
@@ -695,7 +695,7 @@ static void *fv_queue_thread(void *opaqu
     struct fuse_session *se = qi->virtio_dev->se;
     GThreadPool *pool;
 
-    pool = g_thread_pool_new(fv_queue_worker, qi, se->thread_pool_size, TRUE,
+    pool = g_thread_pool_new(fv_queue_worker, qi, se->thread_pool_size, FALSE,
                              NULL);
     if (!pool) {
         fuse_log(FUSE_LOG_ERR, "%s: g_thread_pool_new failed\n", __func__);