From: Alexandre Chartre <alexandre.chartre@oracle.com>
To: Borislav Petkov <bp@alien8.de>
Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
x86@kernel.org, dave.hansen@linux.intel.com, luto@kernel.org,
peterz@infradead.org, linux-kernel@vger.kernel.org,
thomas.lendacky@amd.com, jroedel@suse.de, konrad.wilk@oracle.com,
jan.setjeeilers@oracle.com, junaids@google.com,
oweisse@google.com, rppt@linux.vnet.ibm.com, graf@amazon.de,
mgross@linux.intel.com, kuzuno@gmail.com,
Mel Gorman <mgorman@techsingularity.net>
Subject: Re: [RFC][PATCH v2 00/21] x86/pti: Defer CR3 switch to C code
Date: Wed, 18 Nov 2020 20:37:57 +0100 [thread overview]
Message-ID: <408004fa-b143-7e12-150a-0dfab12d34ee@oracle.com> (raw)
In-Reply-To: <20201118112952.GB7472@zn.tnic>
On 11/18/20 12:29 PM, Borislav Petkov wrote:
> On Wed, Nov 18, 2020 at 08:41:42AM +0100, Alexandre Chartre wrote:
>> Well, it looks like I wrongfully assume that KPTI was a well known performance
>> overhead since it was introduced (because it adds extra page-table switches),
>> but you are right I should be presenting my own numbers.
>
> Here's one recipe, courtesy of Mel:
>
> https://github.com/gormanm/mmtests
>
Thanks for the detailed information, I have run the test and I see the same difference
as with the tools/perf and libMICRO I already sent: there's a 150% difference for
getpid() with and without pti.
alex.
-----
# ../../compare-kernels.sh --baseline test-nopti --compare test-pti
poundsyscall
test test
nopti pti
Min 2 1.99 ( 0.00%) 5.08 (-155.28%)
Min 4 1.02 ( 0.00%) 2.60 (-154.90%)
Min 6 0.94 ( 0.00%) 2.07 (-120.21%)
Min 8 0.81 ( 0.00%) 1.60 ( -97.53%)
Min 12 0.85 ( 0.00%) 1.65 ( -94.12%)
Min 18 0.82 ( 0.00%) 1.61 ( -96.34%)
Min 24 0.81 ( 0.00%) 1.60 ( -97.53%)
Min 30 0.81 ( 0.00%) 1.60 ( -97.53%)
Min 32 0.81 ( 0.00%) 1.60 ( -97.53%)
Amean 2 2.02 ( 0.00%) 5.10 *-151.83%*
Amean 4 1.03 ( 0.00%) 2.61 *-151.98%*
Amean 6 0.96 ( 0.00%) 2.07 *-116.74%*
Amean 8 0.82 ( 0.00%) 1.60 * -96.56%*
Amean 12 0.87 ( 0.00%) 1.67 * -91.73%*
Amean 18 0.82 ( 0.00%) 1.63 * -97.94%*
Amean 24 0.81 ( 0.00%) 1.60 * -97.41%*
Amean 30 0.82 ( 0.00%) 1.60 * -96.93%*
Amean 32 0.82 ( 0.00%) 1.60 * -96.56%*
Stddev 2 0.02 ( 0.00%) 0.02 ( 33.78%)
Stddev 4 0.01 ( 0.00%) 0.01 ( 7.18%)
Stddev 6 0.01 ( 0.00%) 0.00 ( 68.77%)
Stddev 8 0.01 ( 0.00%) 0.01 ( 10.56%)
Stddev 12 0.01 ( 0.00%) 0.02 ( -12.69%)
Stddev 18 0.01 ( 0.00%) 0.01 (-107.25%)
Stddev 24 0.00 ( 0.00%) 0.00 ( -14.56%)
Stddev 30 0.01 ( 0.00%) 0.01 ( 0.00%)
Stddev 32 0.01 ( 0.00%) 0.00 ( 20.00%)
CoeffVar 2 1.17 ( 0.00%) 0.31 ( 73.70%)
CoeffVar 4 0.82 ( 0.00%) 0.30 ( 63.16%)
CoeffVar 6 1.41 ( 0.00%) 0.20 ( 85.59%)
CoeffVar 8 0.87 ( 0.00%) 0.39 ( 54.50%)
CoeffVar 12 1.66 ( 0.00%) 0.98 ( 41.23%)
CoeffVar 18 0.85 ( 0.00%) 0.89 ( -4.71%)
CoeffVar 24 0.52 ( 0.00%) 0.30 ( 41.97%)
CoeffVar 30 0.65 ( 0.00%) 0.33 ( 49.22%)
CoeffVar 32 0.65 ( 0.00%) 0.26 ( 59.30%)
Max 2 2.04 ( 0.00%) 5.13 (-151.47%)
Max 4 1.04 ( 0.00%) 2.62 (-151.92%)
Max 6 0.98 ( 0.00%) 2.08 (-112.24%)
Max 8 0.83 ( 0.00%) 1.62 ( -95.18%)
Max 12 0.89 ( 0.00%) 1.70 ( -91.01%)
Max 18 0.84 ( 0.00%) 1.66 ( -97.62%)
Max 24 0.82 ( 0.00%) 1.61 ( -96.34%)
Max 30 0.82 ( 0.00%) 1.61 ( -96.34%)
Max 32 0.82 ( 0.00%) 1.61 ( -96.34%)
BAmean-50 2 2.01 ( 0.00%) 5.09 (-153.39%)
BAmean-50 4 1.03 ( 0.00%) 2.60 (-152.62%)
BAmean-50 6 0.95 ( 0.00%) 2.07 (-118.82%)
BAmean-50 8 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-50 12 0.86 ( 0.00%) 1.66 ( -92.79%)
BAmean-50 18 0.82 ( 0.00%) 1.62 ( -97.56%)
BAmean-50 24 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-50 30 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-50 32 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-95 2 2.02 ( 0.00%) 5.09 (-151.87%)
BAmean-95 4 1.03 ( 0.00%) 2.61 (-151.99%)
BAmean-95 6 0.95 ( 0.00%) 2.07 (-117.25%)
BAmean-95 8 0.81 ( 0.00%) 1.60 ( -96.72%)
BAmean-95 12 0.87 ( 0.00%) 1.67 ( -91.82%)
BAmean-95 18 0.82 ( 0.00%) 1.63 ( -97.97%)
BAmean-95 24 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-95 30 0.81 ( 0.00%) 1.60 ( -97.00%)
BAmean-95 32 0.81 ( 0.00%) 1.60 ( -96.59%)
BAmean-99 2 2.02 ( 0.00%) 5.09 (-151.87%)
BAmean-99 4 1.03 ( 0.00%) 2.61 (-151.99%)
BAmean-99 6 0.95 ( 0.00%) 2.07 (-117.25%)
BAmean-99 8 0.81 ( 0.00%) 1.60 ( -96.72%)
BAmean-99 12 0.87 ( 0.00%) 1.67 ( -91.82%)
BAmean-99 18 0.82 ( 0.00%) 1.63 ( -97.97%)
BAmean-99 24 0.81 ( 0.00%) 1.60 ( -97.53%)
BAmean-99 30 0.81 ( 0.00%) 1.60 ( -97.00%)
BAmean-99 32 0.81 ( 0.00%) 1.60 ( -96.59%)
test test
nopti pti
Duration User 150.13 432.03
Duration System 372.10 657.69
Duration Elapsed 94.17 199.27
next prev parent reply other threads:[~2020-11-18 19:38 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-16 14:47 [RFC][PATCH v2 00/21] x86/pti: Defer CR3 switch to C code Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 01/21] x86/syscall: Add wrapper for invoking syscall function Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 02/21] x86/entry: Update asm_call_on_stack to support more function arguments Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 03/21] x86/entry: Consolidate IST entry from userspace Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 04/21] x86/sev-es: Define a setup stack function for the VC idtentry Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 05/21] x86/entry: Implement ret_from_fork body with C code Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 06/21] x86/pti: Provide C variants of PTI switch CR3 macros Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 07/21] x86/entry: Fill ESPFIX stack using C code Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 08/21] x86/pti: Introduce per-task PTI trampoline stack Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 09/21] x86/pti: Function to clone page-table entries from a specified mm Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 10/21] x86/pti: Function to map per-cpu page-table entry Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 11/21] x86/pti: Extend PTI user mappings Alexandre Chartre
2020-11-16 19:48 ` Andy Lutomirski
2020-11-16 20:21 ` Alexandre Chartre
2020-11-16 23:06 ` Andy Lutomirski
2020-11-17 8:42 ` Alexandre Chartre
2020-11-17 15:49 ` Andy Lutomirski
2020-11-19 19:15 ` Thomas Gleixner
2020-11-16 14:47 ` [RFC][PATCH v2 12/21] x86/pti: Use PTI stack instead of trampoline stack Alexandre Chartre
2020-11-16 16:57 ` Andy Lutomirski
2020-11-16 18:10 ` Alexandre Chartre
2020-11-16 18:34 ` Andy Lutomirski
2020-11-16 19:37 ` Alexandre Chartre
2020-11-17 15:09 ` Alexandre Chartre
2020-11-17 15:52 ` Andy Lutomirski
2020-11-17 17:01 ` Alexandre Chartre
2020-11-19 1:49 ` Andy Lutomirski
2020-11-19 8:05 ` Alexandre Chartre
2020-11-19 12:06 ` Alexandre Chartre
2020-11-19 16:06 ` Andy Lutomirski
2020-11-19 17:02 ` Alexandre Chartre
2020-11-16 21:24 ` David Laight
2020-11-17 8:27 ` Alexandre Chartre
2020-11-19 19:10 ` Thomas Gleixner
2020-11-19 19:55 ` Alexandre Chartre
2020-11-19 21:20 ` Thomas Gleixner
2020-11-24 7:20 ` [x86/pti] 5da9e742d1: PANIC:double_fault kernel test robot
2020-11-16 14:47 ` [RFC][PATCH v2 13/21] x86/pti: Execute syscall functions on the kernel stack Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 14/21] x86/pti: Execute IDT handlers " Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 15/21] x86/pti: Execute IDT handlers with error code " Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 16/21] x86/pti: Execute system vector handlers " Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 17/21] x86/pti: Execute page fault handler " Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 18/21] x86/pti: Execute NMI " Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 19/21] x86/pti: Defer CR3 switch to C code for IST entries Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 20/21] x86/pti: Defer CR3 switch to C code for non-IST and syscall entries Alexandre Chartre
2020-11-16 14:47 ` [RFC][PATCH v2 21/21] x86/pti: Use a different stack canary with the user and kernel page-table Alexandre Chartre
2020-11-16 16:56 ` Andy Lutomirski
2020-11-16 18:34 ` Alexandre Chartre
2020-11-16 20:17 ` [RFC][PATCH v2 00/21] x86/pti: Defer CR3 switch to C code Borislav Petkov
2020-11-17 7:56 ` Alexandre Chartre
2020-11-17 16:55 ` Borislav Petkov
2020-11-17 18:12 ` Alexandre Chartre
2020-11-17 18:28 ` Borislav Petkov
2020-11-17 19:02 ` Alexandre Chartre
2020-11-17 21:23 ` Borislav Petkov
2020-11-18 7:08 ` Alexandre Chartre
2020-11-17 21:26 ` Borislav Petkov
2020-11-18 7:41 ` Alexandre Chartre
2020-11-18 9:30 ` David Laight
2020-11-18 10:29 ` Alexandre Chartre
2020-11-18 13:22 ` David Laight
2020-11-18 17:15 ` Alexandre Chartre
2020-11-18 11:29 ` Borislav Petkov
2020-11-18 19:37 ` Alexandre Chartre [this message]
2020-11-16 20:24 ` Borislav Petkov
2020-11-17 8:19 ` Alexandre Chartre
2020-11-17 17:07 ` Borislav Petkov
2020-11-17 18:24 ` Alexandre Chartre
2020-11-19 19:32 ` Thomas Gleixner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=408004fa-b143-7e12-150a-0dfab12d34ee@oracle.com \
--to=alexandre.chartre@oracle.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=graf@amazon.de \
--cc=hpa@zytor.com \
--cc=jan.setjeeilers@oracle.com \
--cc=jroedel@suse.de \
--cc=junaids@google.com \
--cc=konrad.wilk@oracle.com \
--cc=kuzuno@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mgorman@techsingularity.net \
--cc=mgross@linux.intel.com \
--cc=mingo@redhat.com \
--cc=oweisse@google.com \
--cc=peterz@infradead.org \
--cc=rppt@linux.vnet.ibm.com \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).