df4a902509
'lookup' is always followed by 'add'. Merge both and make the list-walk part of nf_conncount_add(). This also avoids one unneeded unlock/re-lock pair. Extra care needs to be taken in count_tree, as we only hold rcu read lock, i.e. we can only insert to an existing tree node after acquiring its lock and making sure it has a nonzero count. As a zero count should be rare, just fall back to insert_tree() (which acquires tree lock). This issue and its solution were pointed out by Shawn Bohrer during patch review. Reviewed-by: Shawn Bohrer <sbohrer@cloudflare.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.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.