Re: [PATCH] store trace default-collect to target [3/6] tfile

Hui Zhu
2013-04-12T10:46:01Z

Hi Yao,

Thanks for your patch.

I should do it but I didn't because when I work on this part I cannot
find example in GDB src bceause the code that can be example is still
not check in. :P

Best,
Hui

On Thu, Apr 11, 2013 at 8:53 PM, Yao Qi <yao@codesourcery.com> wrote:
> On 04/11/2013 02:17 PM, Hui Zhu wrote:
>> /* This is the implementation of trace_file_write_ops method
>> + write_default_collect. */
>> +
>> +static void
>> +ctf_write_default_collect (struct trace_file_writer *self,
>> + char *collect)
>> +{
>> + /* It is not supported yet to write default collect
>> + into CTF trace data. */
>> +}
>> +
>
> It is pity to see "default-collect" is not written to CTF in this
> patch. The patch below is about teaching GDB to write
> "default-collect" action in CTF and read "default-collect" action from
> CTF. Do you mind incorporating the patch below into your patch series,
> so that your series is more complete.
>
> --
> Yao (齐尧)
>
> gdb:
>
> 2013-04-11 Yao Qi <yao@codesourcery.com>
>
> * ctf.c (CTF_EVENT_ID_DEFAULT_COLLECT): New macro.
> (ctf_write_header): Write metadata for "default-collect"
> action.
> (ctf_write_default_collect): Write "default-collect" action
> in CTF.
> (ctf_read_default_collect): New.
> (ctf_open): Call ctf_read_default_collect.
> ---
> gdb/ctf.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> 1 files changed, 57 insertions(+), 2 deletions(-)
>
> diff --git a/gdb/ctf.c b/gdb/ctf.c
> index 2dd2ed8..5757b47 100644
> --- a/gdb/ctf.c
> +++ b/gdb/ctf.c
> @@ -74,6 +74,7 @@
> #define CTF_EVENT_ID_STATUS 4
> #define CTF_EVENT_ID_TSV_DEF 5
> #define CTF_EVENT_ID_TP_DEF 6
> +#define CTF_EVENT_ID_DEFAULT_COLLECT 7
>
> /* The state kept while writing the CTF datastream file. */
>
> @@ -428,6 +429,16 @@ ctf_write_header (struct trace_file_writer *self)
> "\t};\n"
> "};\n", CTF_EVENT_ID_TP_DEF);
>
> + ctf_save_write_metadata (&writer->tcs, "\n");
> + ctf_save_write_metadata (&writer->tcs,
> + "event {\n\tname = \"default_collect\";\n"
> + "\tid = %u;\n"
> + "\tfields := struct { \n"
> + "\t\tchars contents;\n"
> + "\t};\n"
> + "};\n",
> + CTF_EVENT_ID_DEFAULT_COLLECT);
> +
> gdb_assert (writer->tcs.content_size == 0);
> gdb_assert (writer->tcs.packet_start == 0);
>
> @@ -622,8 +633,17 @@ static void
> ctf_write_default_collect (struct trace_file_writer *self,
> char *collect)
> {
> - /* It is not supported yet to write default collect
> - into CTF trace data. */
> + struct ctf_trace_file_writer *writer
> + = (struct ctf_trace_file_writer *) self;
> + int32_t int32;
> +
> + /* Event Id. */
> + int32 = CTF_EVENT_ID_DEFAULT_COLLECT;
> + ctf_save_align_write (&writer->tcs, (gdb_byte *) &int32, 4, 4);
> +
> + /* Contents. */
> + ctf_save_write (&writer->tcs, collect, strlen (collect) + 1);
> +
> }
>
> /* This is the implementation of trace_file_write_ops method
> @@ -1149,6 +1169,39 @@ ctf_read_tp (struct uploaded_tp **uploaded_tps)
> }
> }
>
> +/* Read a CTF event on "default-collect" and update the
> + "default-collect" action. */
> +
> +static void
> +ctf_read_default_collect (void)
> +{
> + struct bt_ctf_event *event;
> + const struct bt_definition *scope;
> + uint32_t u32;
> + char *default_collect;
> +
> + event = bt_ctf_iter_read_event (ctf_iter);
> + scope = bt_ctf_get_top_level_scope (event,
> + BT_STREAM_EVENT_HEADER);
> + u32 = bt_ctf_get_uint64 (bt_ctf_get_field (event, scope,
> + "id"));
> +
> + if (u32 != CTF_EVENT_ID_DEFAULT_COLLECT)
> + error (_("Wrong event id!"));
> +
> + default_collect
> + = bt_ctf_get_string (bt_ctf_get_field (event, scope, "contents"));
> +
> + if (default_collect == NULL)
> + default_collect = xstrdup ("");
> + else
> + default_collect = xstrdup (default_collect);
> +
> + trace_set_default_collect (default_collect);
> +
> + bt_iter_next (bt_ctf_get_iter (ctf_iter));
> +}
> +
> /* This is the implementation of target_ops method to_open. Open CTF
> trace data, read trace status, trace state variables and tracepoint
> definitions from the first packet. Set the start position at the
> @@ -1190,6 +1243,8 @@ ctf_open (char *dirname, int from_tty)
>
> ctf_read_tp (&uploaded_tps);
>
> + ctf_read_default_collect ();
> +
> event = bt_ctf_iter_read_event (ctf_iter);
> /* EVENT can be NULL if we've already gone to the end of stream of
> events. */
> --
> 1.7.7.6