search for: write_completed

Hi all, I''ve been working on the win32-pipe library (again) and I''ve reworked the interface. Instead of Pipe.new_server or Pipe.new_client, there''s now a base Pipe class, with Pipe::Server and Pipe::Client subclasses. You can find the latest code in the CVS repo. Oh, and you''ll need to update your windows-pr library with the latest from CVS if you want to

...~completion:(read_completed buf !soff)); soff := !soff +^ bs ); @@ -59,7 +59,8 @@ let asynch_copy src dst = List.iter ( fun (buf, offset) -> (* Note the size of the write is implicitly stored in buf. *) - ignore (NBD.aio_pwrite_callback dst buf offset (write_completed buf)) + ignore (NBD.aio_pwrite_callback dst buf offset + ~completion:(write_completed buf)) ) !writes; writes := []; diff --git a/ocaml/tests/test_505_aio_pread_structured_callback.ml b/ocaml/tests/test_505_aio_pread_structured_callback.ml index 9b9ac2c..dc0d557...

...~completion:(read_completed buf !soff)); soff := !soff +^ bs ); @@ -59,7 +59,8 @@ let asynch_copy src dst = List.iter ( fun (buf, offset) -> (* Note the size of the write is implicitly stored in buf. *) - ignore (NBD.aio_pwrite_callback dst buf offset (write_completed buf)) + ignore (NBD.aio_pwrite_callback dst buf offset + ~completion:(write_completed buf)) ) !writes; writes := []; diff --git a/ocaml/tests/test_505_aio_pread_structured_callback.ml b/ocaml/tests/test_505_aio_pread_structured_callback.ml index 9b9ac2c..dc0d557...

...+ global bytes_read + bytes_read += buf.size () + wr = (buf, offset) + writes.append (wr) + # By returning 1 here we auto-retire the pread command. + return 1 + + # This callback is called when any pwrite to the destination + # has completed. + def write_completed (buf, error): + global bytes_written + bytes_written += buf.size () + # By returning 1 here we auto-retire the pwrite command. + return 1 + + # The main loop which runs until we have finished reading and + # there are no more commands in flight. + while soff &lt...

v1 was here: https://www.redhat.com/archives/libguestfs/2019-August/msg00168.html I pushed uncontroversial patches 1-4 v2: - The implementation of OClosure (new patch 1) in Python is fixed. - Patch 2 (old patch 5) is unchanged. - I added a new API for removing debug callbacks. I think this approach has some advantages over using OClosure. - I didn't yet do any work on changing the

...s/asynch_copy.ml +++ b/ocaml/examples/asynch_copy.ml @@ -31,11 +31,9 @@ let asynch_copy src dst = in (* This callback is called when any pwrite to the destination - * has completed. We have to manually free the buffer here - * as it is no longer used. + * has completed. *) let write_completed buf _ = - NBD.Buffer.free buf; (* By returning 1 here we auto-retire the pwrite command. *) 1 in diff --git a/ocaml/libnbd-ocaml.pod b/ocaml/libnbd-ocaml.pod index f5f968c..5e161c6 100644 --- a/ocaml/libnbd-ocaml.pod +++ b/ocaml/libnbd-ocaml.pod @@ -34,28 +34,6 @@ which is the print...

...s/asynch_copy.ml +++ b/ocaml/examples/asynch_copy.ml @@ -31,11 +31,9 @@ let asynch_copy src dst = in (* This callback is called when any pwrite to the destination - * has completed. We have to manually free the buffer here - * as it is no longer used. + * has completed. *) let write_completed buf _ = - NBD.Buffer.free buf; (* By returning 1 here we auto-retire the pwrite command. *) 1 in diff --git a/ocaml/libnbd-ocaml.pod b/ocaml/libnbd-ocaml.pod index d370113..ae8fb88 100644 --- a/ocaml/libnbd-ocaml.pod +++ b/ocaml/libnbd-ocaml.pod @@ -33,28 +33,6 @@ which is the print...

v1 was here: https://www.redhat.com/archives/libguestfs/2019-August/msg00103.html In v2 I've made several changes: - Fix Python callbacks so if they don't return something which is int-like, we assume they mean to return 0. - Add nbd.Buffer free() method. Read commit message in patch 2 to see what this is about. - Fixed the asynch copy test to deal with the unbelievably

Basically the same as this patch series, but for Python: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html plus adding the 590 asynch test at the end. Rich.

In this patch series we use the newly introduced free callback on the completion function to dererence the OCaml NBD.Buffer. I will make the same kind of change for Python later in a separate series. The completion function is always called at the C level, even if the OCaml program didn't use the optional argument. That's because the free callback doesn't run otherwise. There is a

This is a combination of these two earlier series: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html https://www.redhat.com/archives/libguestfs/2019-August/msg00240.html plus changes to allow .callback = NULL / .free != NULL, and to reduce the complexity of freeing callbacks. Although it's rather long there's nothing complex here. We might consider squashing some

Patches 1-4 are basically uncontroversial, straightforward refactoring and IMHO we should just push them. Possibly 1-3 should be squashed together, but I posted them separately so they are easier to review. Patches 5 and 6 together implement OClosure. Patch 5 adds the feature and is simple to understand. Patch 6 changes the Closure completion callbacks into OClosure, but because it doesn't

..._copy src dst = > List.iter ( > fun (buf, offset) -> > (* Note the size of the write is implicitly stored in buf. *) > - ignore (NBD.aio_pwrite_callback dst buf offset > + ignore (NBD.aio_pwrite dst buf offset > ~completion:(write_completed buf)) and here > +++ b/ocaml/tests/test_590_aio_copy.ml > @@ -71,7 +71,7 @@ let asynch_copy src dst = > if !soff < size && NBD.aio_in_flight src < max_reads_in_flight then ( > let bs = min bs (size -^ !soff) in > let buf = NBD.Buffer.alloc (Int64.t...

This applies on top of the OClosure v2 series posted a few minutes ago. Rich.

..._callback cb, + void *user_data); + +C<ptr> is a pointer to the object (ie. the buffer or +callback C<user_data>). C<cb (ptr)> is called when libnbd +no longer holds a reference to that object. + +To illustrate how this works with an example: + + struct write_completed_user_data *my_user_data; + void *buf; + + my_user_data = malloc (sizeof *my_user_data); + buf = malloc (512); + nbd_add_free_callback (nbd, my_user_data, my_free, NULL); + nbd_add_free_callback (nbd, buf, my_free, NULL); + nbd_aio_pwrite_callback (nbd, buf, 512, 0, + write...

This doesn't yet work. However it does make me more convinced than ever that we really need to sort out persistent buffer lifetimes in the library (similar to what we did for closures). Rich.

...example: + + struct my_user_data *my_user_data; + void *buf; + + my_user_data = malloc (sizeof *my_user_data); + buf = malloc (512); + nbd_add_free_callback (nbd, free, my_user_data); + nbd_add_free_callback (nbd, free, buf); + nbd_aio_pwrite_callback (nbd, buf, 512, 0, + write_completed, my_user_data, 0); + +This would free both C<my_user_data> and C<buf> once libnbd +has finished with them. + =head1 SEE ALSO L<libnbd(3)>. -- 2.22.0

...; @@ -59,7 +59,7 @@ let asynch_copy src dst = List.iter ( fun (buf, offset) -> (* Note the size of the write is implicitly stored in buf. *) - ignore (NBD.aio_pwrite_callback dst buf offset + ignore (NBD.aio_pwrite dst buf offset ~completion:(write_completed buf)) ) !writes; writes := []; diff --git a/ocaml/tests/test_505_aio_pread_structured_callback.ml b/ocaml/tests/test_505_aio_pread_structured_callback.ml index dc0d557..075ec85 100644 --- a/ocaml/tests/test_505_aio_pread_structured_callback.ml +++ b/ocaml/tests/test_505_aio_pread_structur...

As proposed here: https://www.redhat.com/archives/libguestfs/2019-August/msg00130.html I didn't actually read Eric's replies to that yet because I've been concentrating on writing these patches all day. Anyway here they are and I'll look at what Eric said about the proposal next. Rich.

Now runs a complete set of tests, notably including the AIO test. File descriptors are passed in and out as plain ints (instead of *os.File) for a couple of reasons: (1) We have to pass the plain int to syscall.Select. (2) Turning an fd into an os.File causes golang to set the blocking flag which is deeply unhelpful. Rich.