On 24.06.21 12:28, Julien Grall wrote:
> Hi Juergen,
> 
> On 24/06/2021 10:41, Juergen Gross wrote:
>> On 16.06.21 16:43, Julien Grall wrote:
>>> From: Julien Grall <jgrall@amazon.com>
>>>
>>> Currently, only Live-Update request can be delayed. In a follow-up,
>>> we will want to delay more requests (e.g. transaction start).
>>> Therefore we want to preserve delayed requests across Live-Update.
>>>
>>> Delayed requests are just complete "in" buffer. So the code is
>>> refactored to allow sharing the code to dump "in" buffer.
>>>
>>> Signed-off-by: Julien Grall <jgrall@amazon.com>
>>> ---
>>>   tools/xenstore/xenstored_core.c | 42 +++++++++++++++++++++++++--------
>>>   1 file changed, 32 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/tools/xenstore/xenstored_core.c 
>>> b/tools/xenstore/xenstored_core.c
>>> index 5b7ab7f74013..9eca58682b51 100644
>>> --- a/tools/xenstore/xenstored_core.c
>>> +++ b/tools/xenstore/xenstored_core.c
>>> @@ -2403,25 +2403,47 @@ const char *dump_state_global(FILE *fp)
>>>       return NULL;
>>>   }
>>> +static const char *dump_input_buffered_data(FILE *fp,
>>> +                        conststruct buffered_data *in,
>>> +                        unsigned int *total_len)
>>> +{
>>> +    unsigned int hlen = in->inhdr ? in->used : sizeof(in->hdr);
>>> +
>>> +    *total_len += hlen;
>>> +    if (fp && fwrite(&in->hdr, hlen, 1, fp) != 1)
>>> +        return "Dump read data error";
>>> +    if (!in->inhdr && in->used) {
>>> +        *total_len += in->used;
>>> +        if (fp && fwrite(in->buffer,in->used, 1, fp) != 1)
>>> +            return "Dump read data error";
>>> +    }
>>> +
>>> +    return NULL;
>>> +}
>>> +
>>>   /* Called twice: first with fp == NULL to get length, then 
for 
>>> writing data. */
>>>   const char *dump_state_buffered_data(FILE *fp, const struct 
>>> connection *c,
>>>                        struct xs_state_connection *sc)
>>>   {
>>>       unsigned int len = 0, used;
>>> -    struct buffered_data *out, *in = c->in;
>>> +    struct buffered_data *out;
>>>       bool partial = true;
>>> +    struct delayed_request *req;
>>> +    const char *ret;
>>> -    if (in) {
>>> -        len = in->inhdr ? in->used: sizeof(in->hdr);
>>> -        if (fp && fwrite(&in->hdr, len, 1, fp) != 1)
>>> -            return "Dump read data error";
>>> -        if (!in->inhdr && in->used) {
>>> -            len += in->used;
>>> -            if (fp && fwrite(in->buffer, in->used, 1, fp) != 1)
>>> -                return "Dump read data error";
>>> -        }
>>> +    /* Dump any command that was delayed */
>>> +    list_for_each_entry(req, &c->delayed, list) {
>>
>> Please add a comment here that the following if() serves especially to
>> avoid dumping the data for do_lu_start().
> 
> Would you be happy to give your acked-by/reviewed-by if I add the 
> following on commit?
> 
> "
> We only want to preserve commands that wasn't processed at all. All the 


s/wasn't/weren't/

> other delayed requests (such as do_lu_start()) must be processed before 

> Live-Update.
> "

With that change I'm fine.


Juergen