From: Dan Williams <dan.j.williams@intel.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
Erik Kaneda <erik.kaneda@intel.com>,
Rafael J Wysocki <rafael.j.wysocki@intel.com>,
Len Brown <lenb@kernel.org>, Borislav Petkov <bp@alien8.de>,
Ira Weiny <ira.weiny@intel.com>,
James Morse <james.morse@arm.com>,
Myron Stowe <myron.stowe@redhat.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Linux ACPI <linux-acpi@vger.kernel.org>,
linux-nvdimm <linux-nvdimm@lists.01.org>,
Bob Moore <robert.moore@intel.com>
Subject: Re: [RFT][PATCH v3 0/4] ACPI: ACPICA / OSL: Avoid unmapping ACPI memory inside of the AML interpreter
Date: Mon, 29 Jun 2020 13:46:03 -0700 [thread overview]
Message-ID: <CAPcyv4iZA6hHH=sh=CZPJ-6skJfeuAVRVAuMeTdD5LYVPRrTqQ@mail.gmail.com> (raw)
In-Reply-To: <CAJZ5v0h4Hj4ax1mmMJn3z3VGtVWkoXzO0kOQ7CYnFKJV2cUGzw@mail.gmail.com>
On Sun, Jun 28, 2020 at 10:09 AM Rafael J. Wysocki <rafael@kernel.org> wrote:
>
> On Fri, Jun 26, 2020 at 8:41 PM Dan Williams <dan.j.williams@intel.com> wrote:
> >
> > On Fri, Jun 26, 2020 at 10:34 AM Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> > >
> > > Hi All,
> > >
> > > On Monday, June 22, 2020 3:50:42 PM CEST Rafael J. Wysocki wrote:
> > > > Hi All,
> > > >
> > > > This series is to address the problem with RCU synchronization occurring,
> > > > possibly relatively often, inside of acpi_ex_system_memory_space_handler(),
> > > > when the namespace and interpreter mutexes are held.
> > > >
> > > > Like I said before, I had decided to change the approach used in the previous
> > > > iteration of this series and to allow the unmap operations carried out by
> > > > acpi_ex_system_memory_space_handler() to be deferred in the first place,
> > > > which is done in patches [1-2/4].
> > >
> > > In the meantime I realized that calling syncrhonize_rcu_expedited() under the
> > > "tables" mutex within ACPICA is not quite a good idea too and that there is no
> > > reason for any users of acpi_os_unmap_memory() in the tree to use the "sync"
> > > variant of unmapping.
> > >
> > > So, unless I'm missing something, acpi_os_unmap_memory() can be changed to
> > > always defer the final unmapping and the only ACPICA change needed to support
> > > that is the addition of the acpi_os_release_unused_mappings() call to get rid
> > > of the unused mappings when leaving the interpreter (module the extra call in
> > > the debug code for consistency).
> > >
> > > So patches [1-2/4] have been changed accordingly.
> > >
> > > > However, it turns out that the "fast-path" mapping is still useful on top of
> > > > the above to reduce the number of ioremap-iounmap cycles for the same address
> > > > range and so it is introduced by patches [3-4/4].
> > >
> > > Patches [3-4/4] still do what they did, but they have been simplified a bit
> > > after rebasing on top of the new [1-2/4].
> > >
> > > The below information is still valid, but it applies to the v3, of course.
> > >
> > > > For details, please refer to the patch changelogs.
> > > >
> > > > The series is available from the git branch at
> > > >
> > > > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git \
> > > > acpica-osl
> > > >
> > > > for easier testing.
> > >
> > > Also the series have been tested locally.
> >
> > Ok, I'm still trying to get the original reporter to confirm this
> > reduces the execution time for ASL routines with a lot of OpRegion
> > touches. Shall I rebuild that test kernel with these changes, or are
> > the results from the original RFT still interesting?
>
> I'm mostly interested in the results with the v3 applied.
>
Ok, I just got feedback on v2 and it still showed the 30 minute
execution time where 7 minutes was achieved previously.
> Also it would be good to check the impact of the first two patches
> alone relative to all four.
I'll start with the full set and see if they can also support the
"first 2" experiment.
next prev parent reply other threads:[~2020-06-29 20:46 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-07 23:39 [PATCH v2] ACPI: Drop rcu usage for MMIO mappings Dan Williams
2020-06-05 13:32 ` Rafael J. Wysocki
2020-06-05 16:18 ` Dan Williams
2020-06-05 16:21 ` Rafael J. Wysocki
2020-06-05 16:39 ` Dan Williams
2020-06-05 17:02 ` Rafael J. Wysocki
2020-06-05 14:06 ` [RFT][PATCH] ACPI: OSL: Use rwlock instead of RCU for memory management Rafael J. Wysocki
2020-06-05 17:08 ` Dan Williams
2020-06-06 6:56 ` Rafael J. Wysocki
2020-06-08 15:33 ` Rafael J. Wysocki
2020-06-08 16:29 ` Rafael J. Wysocki
2020-06-05 19:40 ` Andy Shevchenko
2020-06-06 6:48 ` Rafael J. Wysocki
2020-06-10 12:17 ` [RFT][PATCH 0/3] ACPI: ACPICA / OSL: Avoid unmapping ACPI memory inside of the AML interpreter Rafael J. Wysocki
2020-06-10 12:20 ` [RFT][PATCH 1/3] ACPICA: Defer unmapping of memory used in memory opregions Rafael J. Wysocki
2020-06-10 12:21 ` [RFT][PATCH 2/3] ACPICA: Remove unused memory mappings on interpreter exit Rafael J. Wysocki
2020-06-12 0:12 ` Kaneda, Erik
2020-06-12 12:05 ` Rafael J. Wysocki
2020-06-13 19:28 ` Rafael J. Wysocki
2020-06-15 19:06 ` Dan Williams
2020-06-10 12:22 ` [RFT][PATCH 3/3] ACPI: OSL: Define ACPI_OS_MAP_MEMORY_FAST_PATH() Rafael J. Wysocki
2020-06-13 19:19 ` [RFT][PATCH 0/3] ACPI: ACPICA / OSL: Avoid unmapping ACPI memory inside of the AML interpreter Rafael J. Wysocki
2020-06-22 13:50 ` [RFT][PATCH v2 0/4] " Rafael J. Wysocki
2020-06-22 13:52 ` [RFT][PATCH v2 1/4] ACPICA: Defer unmapping of opregion memory if supported by OS Rafael J. Wysocki
2020-06-22 13:53 ` [RFT][PATCH v2 2/4] ACPI: OSL: Add support for deferred unmapping of ACPI memory Rafael J. Wysocki
2020-06-22 14:56 ` Andy Shevchenko
2020-06-22 15:27 ` Rafael J. Wysocki
2020-06-22 15:46 ` Andy Shevchenko
2020-06-22 14:01 ` [RFT][PATCH v2 3/4] ACPICA: Preserve memory opregion mappings if supported by OS Rafael J. Wysocki
2020-06-26 22:53 ` Kaneda, Erik
2020-06-29 13:02 ` Rafael J. Wysocki
2020-06-22 14:02 ` [RFT][PATCH v2 4/4] ACPI: OSL: Implement acpi_os_map_memory_fast_path() Rafael J. Wysocki
2020-06-26 17:28 ` [RFT][PATCH v3 0/4] ACPI: ACPICA / OSL: Avoid unmapping ACPI memory inside of the AML interpreter Rafael J. Wysocki
2020-06-26 17:31 ` [RFT][PATCH v3 1/4] ACPICA: Take deferred unmapping of memory into account Rafael J. Wysocki
2020-06-26 17:31 ` [RFT][PATCH v3 2/4] ACPI: OSL: Implement deferred unmapping of ACPI memory Rafael J. Wysocki
2020-06-26 17:32 ` [RFT][PATCH v3 3/4] ACPICA: Preserve memory opregion mappings if supported by OS Rafael J. Wysocki
2020-06-26 17:33 ` [RFT][PATCH v3 4/4] ACPI: OSL: Implement acpi_os_map_memory_fast_path() Rafael J. Wysocki
2020-06-26 18:41 ` [RFT][PATCH v3 0/4] ACPI: ACPICA / OSL: Avoid unmapping ACPI memory inside of the AML interpreter Dan Williams
2020-06-28 17:09 ` Rafael J. Wysocki
2020-06-29 20:46 ` Dan Williams [this message]
2020-06-30 11:04 ` Rafael J. Wysocki
2020-06-29 16:31 ` [PATCH v4 0/2] " Rafael J. Wysocki
2020-06-29 16:33 ` [PATCH v4 1/2] ACPI: OSL: Implement deferred unmapping of ACPI memory Rafael J. Wysocki
2020-06-29 16:33 ` [PATCH v4 2/2] ACPICA: Preserve memory opregion mappings Rafael J. Wysocki
2020-06-29 20:57 ` Al Stone
2020-06-30 11:44 ` Rafael J. Wysocki
2020-06-30 15:31 ` Al Stone
2020-06-30 15:52 ` Rafael J. Wysocki
2020-06-30 19:57 ` Al Stone
2020-07-16 19:22 ` Verma, Vishal L
2020-07-19 19:14 ` Rafael J. Wysocki
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='CAPcyv4iZA6hHH=sh=CZPJ-6skJfeuAVRVAuMeTdD5LYVPRrTqQ@mail.gmail.com' \
--to=dan.j.williams@intel.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=bp@alien8.de \
--cc=erik.kaneda@intel.com \
--cc=ira.weiny@intel.com \
--cc=james.morse@arm.com \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@lists.01.org \
--cc=myron.stowe@redhat.com \
--cc=rafael.j.wysocki@intel.com \
--cc=rafael@kernel.org \
--cc=rjw@rjwysocki.net \
--cc=robert.moore@intel.com \
/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).