202394178d
The device driver can have kernel thread or worker doing work against a process mm and it is useful for those to test wether the mm is dead or alive to avoid doing useless work. Add an helper to test that so that driver can bail out early if a process is dying. Note that the helper does not perform any lock synchronization and thus is just a hint ie a process might be dying but the helper might still return the process as alive. All HMM functions are safe to use in that case as HMM internal properly protect itself with lock. If driver use this helper with non HMM functions it should ascertain that it is safe to do so. Link: http://lkml.kernel.org/r/20190403193318.16478-11-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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.