On 11/30/2015 04:32 AM, Peter Xu wrote: > This patch only adds the interfaces, but not implements them. > "detach" parameter is made optional, to make sure that all the old > dump-guest-memory requests will still be able to work. > > Signed-off-by: Peter Xu <pet...@redhat.com> > --- > dump.c | 5 +++-- > hmp-commands.hx | 5 +++-- > hmp.c | 9 +++++++-- > qapi-schema.json | 8 ++++++-- > qmp-commands.hx | 6 ++++-- > 5 files changed, 23 insertions(+), 10 deletions(-)
> +++ b/hmp.c
> @@ -1586,8 +1586,10 @@ void hmp_dump_guest_memory(Monitor *mon, const QDict
> *qdict)
> const char *file = qdict_get_str(qdict, "filename");
> bool has_begin = qdict_haskey(qdict, "begin");
> bool has_length = qdict_haskey(qdict, "length");
> + bool has_detach = qdict_haskey(qdict, "detach");
Here, you probe whether 'detach' is present...
> int64_t begin = 0;
> int64_t length = 0;
> + bool detach = false;
...here, you default 'detach' to false,..
> enum DumpGuestMemoryFormat dump_format = DUMP_GUEST_MEMORY_FORMAT_ELF;
> char *prot;
>
> @@ -1615,11 +1617,14 @@ void hmp_dump_guest_memory(Monitor *mon, const QDict
> *qdict)
> if (has_length) {
> length = qdict_get_int(qdict, "length");
> }
> + if (has_detach) {
> + detach = qdict_get_try_bool(qdict, "detach", false);
...therefore, this line is only reachable if 'detach' is present, which
means the default will never be needed.
> + }
>
> prot = g_strconcat("file:", file, NULL);
>
> - qmp_dump_guest_memory(paging, prot, has_begin, begin, has_length, length,
> - true, dump_format, &err);
> + qmp_dump_guest_memory(paging, prot, has_detach, detach, has_begin, begin,
> + has_length, length, true, dump_format, &err);
There are two competing ways to simplify this; I don't care which one
you choose, although you can't do both:
1. Note that since the second assignment to detach only happens if
has_detach is true, you can use the simpler:
if (has_detach) {
detach = qdict_get_bool(qdict, "detach");
}
If you go with this approach, you could even get away without
initializing 'detach' outside of the 'if (has_detach)' conditional
(although it's still probably wiser to avoid uninitialized memory than
to rely on qmp_dump_guest_memory() correctly ignoring 'detach' when
'has_detach' is false).
2. Note that since qdict_get_try_bool() lets you specify a default, you
can eliminate the has_detach variable and instead just do:
bool detach = qdict_get_try_bool(qdict, "detach", false);
...
qmp_dump_guest_memory(paging, prot, true, detach, ...);
> +++ b/qapi-schema.json
> @@ -2115,6 +2115,9 @@
> # 2. fd: the protocol starts with "fd:", and the following string
> # is the fd's name.
> #
> +# @detach: #optional if true, QMP will return immediately rather than
> +# waiting dump to be finished (since 2.6).
s/dump/for the dump/
s/be finished/finish/
> @@ -857,6 +857,8 @@ Arguments:
> - "paging": do paging to get guest's memory mapping (json-bool)
> - "protocol": destination file(started with "file:") or destination file
> descriptor (started with "fd:") (json-string)
> +- "detach": if specificed, command will return immediately, without waiting
s/specificed/specified/
> + for dump to be finished (json-bool)
s/dump/the dump/
s/be finished/finish/
> - "begin": the starting physical address. It's optional, and should be
> specified
> with length together (json-int)
> - "length": the memory size, in bytes. It's optional, and should be specified
>
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
signature.asc
Description: OpenPGP digital signature
