Re: [PATCH v2] audit: unify audit_filter_{uring(),inode_name(),syscall()}

[Ankur Arora <ankur.a.arora@oracle.com>]

Paul Moore <paul@paul-moore.com> writes:

> On Thu, Oct 6, 2022 at 8:49 PM Ankur Arora <ankur.a.arora@oracle.com> wrote:
>>
>> 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>
>> ---
>>  kernel/auditsc.c | 76 +++++++++++++++++++++++++-----------------------
>>  1 file changed, 39 insertions(+), 37 deletions(-)
>
> Thanks, this looks good to me.  I'll queue this up for when the merge
> window closes.

Great. Thanks Paul.

--
ankur