Re: [PATCH 08/11] gdb: optimize check for resumed threads with pending wait status in maybe_set_commit_resumed_all_targets

[Pedro Alves <pedro@palves.net>]

On 2021-06-22 5:57 p.m., Simon Marchi via Gdb-patches wrote:
> Consider a test case where many threads (thousands) keep hitting a
> breakpoint whose condition evaluates to false.
> maybe_set_commit_resumed_all_targets is called at each handled event,
> when the scoped_disable_commit_resumed object in fetch_inferior_event is
> reset_and_commit-ed.  One particularly expensive check in there is
> whether the target has at least one resumed thread with a pending wait
> status (in which case, we don't want to commit the resumed threads, as
> we want to consume this status first).  It is currently implemented as
> walking all threads of the target.
> 
> Since we now maintain a per-target list of resumed threads with pending
> status, we can do this check efficiently, by checking whether that list
> is empty or not.
> 
> Add the process_stratum_target::has_resumed_with_pending_wait_status
> method for this, and use it in maybe_set_commit_resumed_all_targets.
> 
> gdb/ChangeLog:
> 
> 	  * process-stratum-target.h (class process_stratum_target)
> 	  <has_resumed_with_pending_wait_status>: New.
> 	  * infrun.c (maybe_set_commit_resumed_all_targets): Use
> 	  has_resumed_with_pending_wait_status.

OK.