0fd7c5d433
Doing call_rcu() million times a second becomes a bottle neck. Convert non-preallocated hash map from call_rcu to SLAB_TYPESAFE_BY_RCU. The rcu critical section is no longer observed for one htab element which makes non-preallocated hash map behave just like preallocated hash map. The map elements are released back to kernel memory after observing rcu critical section. This improves 'map_perf_test 4' performance from 100k events per second to 250k events per second. bpf_mem_alloc + percpu_counter + typesafe_by_rcu provide 10x performance boost to non-preallocated hash map and make it within few % of preallocated map while consuming fraction of memory. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220902211058.60789-8-alexei.starovoitov@gmail.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.