From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Gautham R Shenoy <ego@linux.vnet.ibm.com>
Cc: Nathan Lynch <nathanl@linux.ibm.com>,
Oliver OHalloran <oliveroh@au1.ibm.com>,
Michael Neuling <mikey@linux.ibm.com>,
Michael Ellerman <michaele@au1.ibm.com>,
Anton Blanchard <anton@au1.ibm.com>,
linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
Nick Piggin <npiggin@au1.ibm.com>
Subject: Re: [PATCH 04/11] powerpc/smp: Enable small core scheduling sooner
Date: Mon, 20 Jul 2020 12:50:16 +0530 [thread overview]
Message-ID: <20200720072016.GE21103@linux.vnet.ibm.com> (raw)
In-Reply-To: <20200717054821.GD25851@in.ibm.com>
* Gautham R Shenoy <ego@linux.vnet.ibm.com> [2020-07-17 11:18:21]:
> On Tue, Jul 14, 2020 at 10:06:17AM +0530, Srikar Dronamraju wrote:
> > Enable small core scheduling as soon as we detect that we are in a
> > system that supports thread group. Doing so would avoid a redundant
> > check.
> >
> > Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
> > Cc: Michael Ellerman <michaele@au1.ibm.com>
> > Cc: Nick Piggin <npiggin@au1.ibm.com>
> > Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
> > Cc: Nathan Lynch <nathanl@linux.ibm.com>
> > Cc: Michael Neuling <mikey@linux.ibm.com>
> > Cc: Anton Blanchard <anton@au1.ibm.com>
> > Cc: Gautham R Shenoy <ego@linux.vnet.ibm.com>
> > Cc: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
> > Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
>
> I don't see a problem with this.
>
> However, since we are now going to be maintaining a single topology
> structure, wouldn't it be better to collate all the changes being made
> to the mask_functions/flags/names of this structure within a single
> function so that it becomes easier to keep track of what all changes
> are going into the topology and why are we doing it?
>
My intent was to move the topology updates early as soon as they are
detected. Currently the shared_cache want cannot be detected early.
But I think its possible to detect shared_cache early with some cleanups.
And if we do, then we should be able to call this up pretty early.
>
> > ---
> > arch/powerpc/kernel/smp.c | 12 ++++++------
> > 1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
> > index 24529f6134aa..7d430fc536cc 100644
> > --- a/arch/powerpc/kernel/smp.c
> > +++ b/arch/powerpc/kernel/smp.c
> > @@ -892,6 +892,12 @@ static int init_big_cores(void)
> > }
> >
> > has_big_cores = true;
> > +
> > +#ifdef CONFIG_SCHED_SMT
> > + pr_info("Big cores detected. Using small core scheduling\n");
> > + powerpc_topology[0].mask = smallcore_smt_mask;
> > +#endif
> > +
> > return 0;
> > }
> >
> > @@ -1383,12 +1389,6 @@ void __init smp_cpus_done(unsigned int max_cpus)
> >
> > dump_numa_cpu_topology();
> >
> > -#ifdef CONFIG_SCHED_SMT
> > - if (has_big_cores) {
> > - pr_info("Big cores detected but using small core scheduling\n");
> > - powerpc_topology[0].mask = smallcore_smt_mask;
> > - }
> > -#endif
> > set_sched_topology(powerpc_topology);
> > }
> >
> > --
> > 2.17.1
> >
--
Thanks and Regards
Srikar Dronamraju
next prev parent reply other threads:[~2020-07-20 7:22 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-14 4:36 [PATCH 00/11] Support for grouping cores Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 01/11] powerpc/smp: Cache node for reuse Srikar Dronamraju
2020-07-17 4:51 ` Gautham R Shenoy
2020-07-14 4:36 ` [PATCH 02/11] powerpc/smp: Merge Power9 topology with Power topology Srikar Dronamraju
2020-07-17 5:44 ` Gautham R Shenoy
2020-07-20 8:10 ` Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 03/11] powerpc/smp: Move powerpc_topology above Srikar Dronamraju
2020-07-17 5:45 ` Gautham R Shenoy
2020-07-14 4:36 ` [PATCH 04/11] powerpc/smp: Enable small core scheduling sooner Srikar Dronamraju
2020-07-17 5:48 ` Gautham R Shenoy
2020-07-20 7:20 ` Srikar Dronamraju [this message]
2020-07-20 7:47 ` Jordan Niethe
2020-07-20 8:52 ` Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 05/11] powerpc/smp: Dont assume l2-cache to be superset of sibling Srikar Dronamraju
2020-07-14 5:40 ` Oliver O'Halloran
2020-07-14 6:30 ` Srikar Dronamraju
2020-07-17 6:00 ` Gautham R Shenoy
2020-07-20 6:45 ` Srikar Dronamraju
2020-07-20 8:58 ` Gautham R Shenoy
2020-07-14 4:36 ` [PATCH 06/11] powerpc/smp: Generalize 2nd sched domain Srikar Dronamraju
2020-07-17 6:37 ` Gautham R Shenoy
2020-07-20 6:19 ` Srikar Dronamraju
2020-07-20 9:07 ` Gautham R Shenoy
2020-07-14 4:36 ` [PATCH 07/11] Powerpc/numa: Detect support for coregroup Srikar Dronamraju
2020-07-17 8:08 ` Gautham R Shenoy
2020-07-20 13:56 ` Michael Ellerman
2020-07-21 2:57 ` Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 08/11] powerpc/smp: Allocate cpumask only after searching thread group Srikar Dronamraju
2020-07-17 8:08 ` Gautham R Shenoy
2020-07-14 4:36 ` [PATCH 09/11] Powerpc/smp: Create coregroup domain Srikar Dronamraju
2020-07-17 8:19 ` Gautham R Shenoy
2020-07-17 8:23 ` Gautham R Shenoy
2020-07-20 6:02 ` Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 10/11] powerpc/smp: Implement cpu_to_coregroup_id Srikar Dronamraju
2020-07-17 8:26 ` Gautham R Shenoy
2020-07-20 5:48 ` Srikar Dronamraju
2020-07-20 9:10 ` Gautham R Shenoy
2020-07-20 10:26 ` Srikar Dronamraju
2020-07-14 4:36 ` [PATCH 11/11] powerpc/smp: Provide an ability to disable coregroup Srikar Dronamraju
2020-07-17 8:28 ` Gautham R Shenoy
2020-07-20 13:57 ` Michael Ellerman
2020-07-14 5:06 ` [PATCH 00/11] Support for grouping cores Srikar Dronamraju
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=20200720072016.GE21103@linux.vnet.ibm.com \
--to=srikar@linux.vnet.ibm.com \
--cc=anton@au1.ibm.com \
--cc=ego@linux.vnet.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=michaele@au1.ibm.com \
--cc=mikey@linux.ibm.com \
--cc=nathanl@linux.ibm.com \
--cc=npiggin@au1.ibm.com \
--cc=oliveroh@au1.ibm.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).