ac71ffcfb4
The PID information can disappear asynchronously because the task can be killed and moved to zombie state. In this case, PID will be zero in similar way to the kernel tasks. Recognize such situation where we are asking to return orphaned object and simply skip filling PID attribute. As part of this change, document the same scenario in counter.c code. Link: https://lore.kernel.org/r/20191010071105.25538-3-leon@kernel.org Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.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.