Fix p9 integration of flipcall.

- Do not call Rread.SetPayload(flipcall packet window) in p9.channel.recv().

- Ignore EINTR from ppoll() in p9.Client.watch().

- Clean up handling of client socket FD lifetimes so that p9.Client.watch()
  never ppoll()s a closed FD.

- Make p9test.Harness.Finish() call clientSocket.Shutdown() instead of
  clientSocket.Close() for the same reason.

- Rework channel reuse to avoid leaking channels in the following case (suppose
  we have two channels):

  sendRecvChannel
    len(channels) == 2 => idx = 1
    inuse[1] = ch0
                                        sendRecvChannel
                                          len(channels) == 1 => idx = 0
                                          inuse[0] = ch1
    inuse[1] = nil
  sendRecvChannel
    len(channels) == 1 => idx = 0
    inuse[0] = ch0
                                          inuse[0] = nil
    inuse[0] == nil => ch0 leaked

- Avoid deadlocking p9.Client.watch() by calling channelsWg.Wait() without
  holding channelsMu.

- Bump p9test:client_test size to medium.

PiperOrigin-RevId: 270200314

2 files changed, 2 insertions, 2 deletions

diff --git a/pkg/p9/p9test/BUILD b/pkg/p9/p9test/BUILD
index 1d34181e0..28707c0ca 100644
--- a/pkg/p9/p9test/BUILD
+++ b/pkg/p9/p9test/BUILD
@@ -77,7 +77,7 @@ go_library(
 
 go_test(
     name = "client_test",
-    size = "small",
+    size = "medium",
     srcs = ["client_test.go"],
     embed = [":p9test"],
     deps = [
diff --git a/pkg/p9/p9test/p9test.go b/pkg/p9/p9test/p9test.go
index 9d74638bb..4d3271b37 100644
--- a/pkg/p9/p9test/p9test.go
+++ b/pkg/p9/p9test/p9test.go
@@ -279,7 +279,7 @@ func (h *Harness) NewSocket() Generator {
 
 // Finish completes all checks and shuts down the server.
 func (h *Harness) Finish() {
-	h.clientSocket.Close()
+	h.clientSocket.Shutdown()
 	h.wg.Wait()
 	h.mockCtrl.Finish()
 }