On 04/22/2016 12:56 AM, Adrian Hunter wrote:
The call_paths table already has symbol_id which belongs uniquely to a DSO,
so why do we need dso_id as well?
If the symbol_id is 0 because the IP could not be resolved to a symbol,
this is not necessarily a valid assumption. Without a dso_id in the
call_paths table, it is not possible to resolve the dso when symbol
information is missing. the db_export api currently does not have enough
information to match a DSO with an IP.
It is often useful to still have the call path associated with a DSO
even if there is no symbol, which i why i recommend keeping the dso_id
in the call_paths table.
Why do you need a callback? Seems like the only thing you need from
thread-stack.c is the call path tree. You could move that to its own .c/.h
files and then process the call chain in db-export.c
My original intent was to reuse existing code with minimal changes and
conform the existing design patterns they used. Thread-stack.c, for
example, currently uses a callback to populate the call_return table, so
I used a callback as well to populate the call_path table.
I am open to making this change if it is believed it will result in a
cleaner implementation.
Also a list of changes like the one above heavily implies you are not
obeying the one patch == one change rule. Please try to make patches that
only do one thing and also run checkpatch.
While i can split this into a few smaller patches there is only really
justification for applying all of them all together. If this is still
preferred i can resubmit this in smaller parts.
If you don't mind, I'll let you respond to my comments before I comment on
any other patches.
Let me know if you have any additional comments.
Thanks,
Chris
