6562c9acb4
perf record __cmd_record() does not poll evlist pollfds. Instead it polls
thread_data[0].pollfd. That happens whether or not threads are being used.
perf record duplicates evlist mmap pollfds as needed for separate threads.
The non-perf-event represented by evlist->ctl_fd has to handled separately,
which is done explicitly, duplicating it into the thread_data[0] pollfds.
That approach neglects any other non-perf-event file descriptors. Currently
there is also done_fd which needs the same handling.
Add a new generalized approach.
Add fdarray_flag__non_perf_event to identify the file descriptors that
need the special handling. For those cases, also keep a mapping of the
evlist pollfd index and thread pollfd index, so that the evlist revents
can be updated.
Although this patch adds the new handling, it does not take it into use.
There is no functional change, but it is the precursor to a fix, so is
marked as a fix.
Fixes: 415ccb58f68a6beb ("perf record: Introduce thread specific data array")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220824072814.16422-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.