Re: [PATCH 103/104] virtiofsd: add --thread-pool-size=NUM option

[Philippe Mathieu-Daudé]

On 12/12/19 5:39 PM, Dr. David Alan Gilbert (git) wrote:

From: Stefan Hajnoczi <stefa...@redhat.com>

Add an option to control the size of the thread pool.  Requests are now
processed in parallel by default.

Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
  tools/virtiofsd/fuse_i.h        | 1 +
  tools/virtiofsd/fuse_lowlevel.c | 7 ++++++-
  tools/virtiofsd/fuse_virtio.c   | 5 +++--
  3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/tools/virtiofsd/fuse_i.h b/tools/virtiofsd/fuse_i.h
index 8a4a05b319..4da6a242ba 100644
--- a/tools/virtiofsd/fuse_i.h
+++ b/tools/virtiofsd/fuse_i.h
@@ -72,6 +72,7 @@ struct fuse_session {
      int   vu_listen_fd;
      int   vu_socketfd;
      struct fv_VuDev *virtio_dev;
+    int thread_pool_size;
  };

struct fuse_chan {

diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 9f01c05e3e..09a7b23726 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -27,6 +27,7 @@
  #include <sys/file.h>
  #include <unistd.h>

+#define THREAD_POOL_SIZE 64 #define OFFSET_MAX 0x7fffffffffffffffLL @@ -2523,6 +2524,7 @@ static const struct fuse_opt fuse_ll_opts[] = {

      LL_OPTION("--socket-path=%s", vu_socket_path, 0),
      LL_OPTION("vhost_user_socket=%s", vu_socket_path, 0),
      LL_OPTION("--fd=%d", vu_listen_fd, 0),
+    LL_OPTION("--thread-pool-size=%d", thread_pool_size, 0),
      FUSE_OPT_END
  };

@@ -2544,7 +2546,9 @@ void fuse_lowlevel_help(void)

          "    --socket-path=PATH         path for the vhost-user socket\n"
          "    -o vhost_user_socket=PATH  path for the vhost-user socket\n"
          "    --fd=FDNUM                 fd number of vhost-user socket\n"
-        "    -o auto_unmount            auto unmount on process 
termination\n");
+        "    -o auto_unmount            auto unmount on process termination\n"
+        "    --thread-pool-size=NUM     thread pool size limit (default %d)\n",
+        THREAD_POOL_SIZE);
  }

void fuse_session_destroy(struct fuse_session *se)

@@ -2598,6 +2602,7 @@ struct fuse_session *fuse_session_new(struct fuse_args 
*args,
      }
      se->fd = -1;
      se->vu_listen_fd = -1;
+    se->thread_pool_size = THREAD_POOL_SIZE;
      se->conn.max_write = UINT_MAX;
      se->conn.max_readahead = UINT_MAX;

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c

index b696ac3135..7bc6ff2f19 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -570,10 +570,11 @@ static void *fv_queue_thread(void *opaque)
      struct fv_QueueInfo *qi = opaque;
      struct VuDev *dev = &qi->virtio_dev->dev;
      struct VuVirtq *q = vu_get_queue(dev, qi->qidx);
+    struct fuse_session *se = qi->virtio_dev->se;
      GThreadPool *pool;

- pool = g_thread_pool_new(fv_queue_worker, qi, 1 /* TODO max_threads */,

-                             TRUE, NULL);
+    pool = g_thread_pool_new(fv_queue_worker, qi, se->thread_pool_size, TRUE,
+                             NULL);
      if (!pool) {
          fuse_log(FUSE_LOG_ERR, "%s: g_thread_pool_new failed\n", __func__);
          return NULL;

Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>