Ankur Arora
50979953c0
audit_filter_uring(), audit_filter_inode_name() are substantially
similar to audit_filter_syscall(). Move the core logic to
__audit_filter_op() which can be parametrized for all three.
On a Skylakex system, getpid() latency (all results aggregated
across 12 boot cycles):
Min Mean Median Max pstdev
(ns) (ns) (ns) (ns)
- 196.63 207.86 206.60 230.98 (+- 3.92%)
+ 183.73 196.95 192.31 232.49 (+- 6.04%)
Performance counter stats for 'bin/getpid' (3 runs) go from:
cycles 805.58 ( +- 4.11% )
instructions 1654.11 ( +- .05% )
IPC 2.06 ( +- 3.39% )
branches 430.02 ( +- .05% )
branch-misses 1.55 ( +- 7.09% )
L1-dcache-loads 440.01 ( +- .09% )
L1-dcache-load-misses 9.05 ( +- 74.03% )
to:
cycles 765.37 ( +- 6.66% )
instructions 1677.07 ( +- 0.04% )
IPC 2.20 ( +- 5.90% )
branches 431.10 ( +- 0.04% )
branch-misses 1.60 ( +- 11.25% )
L1-dcache-loads 521.04 ( +- 0.05% )
L1-dcache-load-misses 6.92 ( +- 77.60% )
(Both aggregated over 12 boot cycles.)
The increased L1-dcache-loads are due to some intermediate values now
coming from the stack.
The improvement in cycles is due to a slightly denser loop (the list
parameter in the list_for_each_entry_rcu() exit check now comes from
a register rather than a constant as before.)
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.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.