archive mirror
 help / color / mirror / Atom feed
From: Beata Michalska <>
Subject: [RFC PATCH v2 1/3] sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag
Date: Wed, 28 Apr 2021 10:32:41 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

Introducing new, complementary to SD_ASYM_CPUCAPACITY, sched_domain
topology flag, to distinguish between shed_domains where any CPU
capacity asymmetry is detected (SD_ASYM_CPUCAPACITY) and ones where
a full range of CPU capacities is visible to all domain members

With the distinction between full and partial CPU capacity asymmetry,
brought in by the newly introduced flag, the scope of the original
SD_ASYM_CPUCAPACITY flag gets shifted, still maintaining the existing
behaviour when one is detected on a given sched domain, allowing
misfit migrations within sched domains that do not observe full range
of CPU capacities but still do have members with different capacity
values. It loses though it's meaning when it comes to the lowest CPU
asymmetry sched_domain level per-cpu pointer, which is to be now

Signed-off-by: Beata Michalska <>
 include/linux/sched/sd_flags.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h
index 34b21e9..57bde66 100644
--- a/include/linux/sched/sd_flags.h
+++ b/include/linux/sched/sd_flags.h
+ * Domain members have different CPU capacities spanning all unique CPU
+ * capacity values.
+ *
+ * SHARED_PARENT: Set from the topmost domain down to the first domain where
+ *		  all available CPU capacities are visible
+ * NEEDS_GROUPS: Per-CPU capacity is asymmetric between groups.
+ */
  * Domain members share CPU capacity (i.e. SMT)
  * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share

  reply	other threads:[~2021-04-28  9:33 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-28  9:32 [RFC PATCH v2 0/3] Rework CPU capacity asymmetry detection Beata Michalska
2021-04-28  9:32 ` Beata Michalska [this message]
2021-04-28  9:32 ` [RFC PATCH v2 2/3] sched/topology: " Beata Michalska
2021-05-05 18:17   ` Valentin Schneider
2021-04-28  9:32 ` [RFC PATCH v2 3/3] sched/doc: Update the CPU capacity asymmetry bits Beata Michalska
2021-04-28 17:19   ` Randy Dunlap
2021-05-10 16:33     ` Beata Michalska
2021-05-05 18:17 ` [RFC PATCH v2 0/3] Rework CPU capacity asymmetry detection Valentin Schneider

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \ \ \ \ \
    --subject='Re: [RFC PATCH v2 1/3] sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

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).