[Libguestfs] [nbdkit PATCH] tests: Don't strand hung nbdkit processes

[Eric Blake]

On 3/20/20 2:47 PM, Eric Blake wrote:
> We've recently been hitting a transient hung rpm build when using make
> 4.3, due to a bug in test-nbd-tls-psk.sh.  We're still trying to
> isolate the correct fix for that bug (it might be in the nbd plugin
> proper, but more likely is an issue in libnbd's tls handling of
> connection close), but in the meantime, this patch should at least
> cause a graceful fail rather than make hanging due to an nbdkit
> process that has hung.
> 
> Signed-off-by: Eric Blake <eblake at redhat.com>
> ---
>   tests/functions.sh.in | 31 ++++++++++++++++++++++++++++---
>   1 file changed, 28 insertions(+), 3 deletions(-)

To see the timeout in action, try applying this temporary patch, then 
running
make -C tests check TESTS=test-nbd-extents.sh

diff --git i/plugins/data/data.c w/plugins/data/data.c
index cfbebc00..8c201ec0 100644
--- i/plugins/data/data.c
+++ w/plugins/data/data.c
@@ -81,10 +81,12 @@ data_load (void)
  }

  /* On unload, free the sparse array. */
+#include <unistd.h>
  static void
  data_unload (void)
  {
    free_sparse_array (sa);
+  sleep(15);
  }

  /* Parse the base64 parameter. */
diff --git i/tests/functions.sh.in w/tests/functions.sh.in
index e483505e..22840c86 100644
--- i/tests/functions.sh.in
+++ w/tests/functions.sh.in
@@ -152,14 +152,14 @@ kill_nbdkit ()

      # Start with SIGTERM, and wait for graceful exit
      kill $pid
-    for i in {1..60}; do
+    for i in {1..10}; do
          if ! kill -0 $pid 2>/dev/null; then
              break
          fi
          sleep 1
      done
      # If nbdkit has not exited, try SIGKILL and fail the test
-    if test $i = 60; then
+    if test $i = 10; then
          echo "error: nbdkit pid $pid failed to respond to SIGTERM"
          kill -9 $pid
          # Append our failure after other cleanups

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org