Re: [Libguestfs] [nbdkit PATCH v2] Introduce cacheextents filter

Apply the attached patch on top of yours which contains miscellaneous fixes. If you use ‘./configure --enable-gcc-warnings’ then it will enable GCC warnings.

The test doesn't really test anything. If extents are being cached then I have two ideas about how you could see that: Either (1) you could look at debug messages, the second extents call shouldn't be processed at the plugin layer. Or (2) write a small nbdkit-sh-plugin script which should see the first extent request and not the second one (and even test that a subsequent write should kill the cache so another extent request is seen by the plugin).

Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/

diff --git a/filters/cacheextents/cacheextents.c b/filters/cacheextents/cacheextents.c index 01c0328..6cd22a7 100644 --- a/filters/cacheextents/cacheextents.c +++ b/filters/cacheextents/cacheextents.c @@ -50,9 +50,6 @@ /* This lock protects the global state. */ static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER; -/* The real size of the underlying plugin. */ -static uint64_t size; - /* Cached extents from the last extents () call and its start and end for the sake of simplicity. */ struct nbdkit_extents *cache_extents; @@ -131,9 +128,8 @@ cacheextents_extents (struct nbdkit_next_ops *next_ops, void *nxdata, } nbdkit_debug ("cacheextents: cache miss"); - int r = next_ops->extents (nxdata, count, offset, flags, extents, err); - if (r == -1) - return r; + if (next_ops->extents (nxdata, count, offset, flags, extents, err) == -1) + return -1; return cacheextents_fill (extents, err); } diff --git a/tests/Makefile.am b/tests/Makefile.am index a2bbaea..aaf7450 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -366,9 +366,7 @@ test_oldstyle_LDADD = libtest.la $(LIBGUESTFS_LIBS) endif HAVE_LIBGUESTFS # Test export flags. -TESTS += \ - test-cacheextents.sh \ - test-eflags.sh +TESTS += test-eflags.sh # common disk image shared with several tests if HAVE_GUESTFISH @@ -868,6 +866,9 @@ TESTS += \ endif HAVE_GUESTFISH TESTS += test-cache-max-size.sh +# cacheextents filter test. +TESTS += test-cacheextents.sh + # cow filter test. if HAVE_GUESTFISH TESTS += test-cow.sh diff --git a/tests/test-cacheextents.sh b/tests/test-cacheextents.sh index fd0bd1c..b9145ed 100755 --- a/tests/test-cacheextents.sh +++ b/tests/test-cacheextents.sh @@ -38,6 +38,10 @@ requires diff --version requires grep --version requires qemu-img --version +files="test-cacheextents-actual.log test-cacheextents-expected.log" +rm -f $files +cleanup_fn rm -f $files + nbdkit \ -U - \ --filter=cacheextents \