virtiofsd: Used glib "shared" thread pool

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>
Message-Id: <20200921213216.GE13362@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  With seccomp fix from Miklos

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 9e5537506c16c90d00ab929c8d93673746699bf8..d5c8e98253b545977e66261103ebc6bfcd4b1b7c 100644 (file)
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -588,7 +588,7 @@ static void *fv_queue_thread(void *opaque)
     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__);

diff --git a/tools/virtiofsd/passthrough_seccomp.c b/tools/virtiofsd/passthrough_seccomp.c
index 19fee60011c59fb8e306e91df2191cc21ead9369..eb9af8265fa1e959a5578b05550bd39af7e36db9 100644 (file)
--- a/tools/virtiofsd/passthrough_seccomp.c
+++ b/tools/virtiofsd/passthrough_seccomp.c
@@ -93,6 +93,8 @@ static const int syscall_whitelist[] = {
     SCMP_SYS(rt_sigaction),
     SCMP_SYS(rt_sigprocmask),
     SCMP_SYS(rt_sigreturn),
+    SCMP_SYS(sched_getattr),
+    SCMP_SYS(sched_setattr),
     SCMP_SYS(sendmsg),
     SCMP_SYS(setresgid),
     SCMP_SYS(setresuid),