linux-kernel - [PATCH] x86/sched: Restore the SD_ASYM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230815035747.11529-1-ricardo.neri-calderon@linux.intel.com>
Date:   Mon, 14 Aug 2023 20:57:47 -0700
From:   Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
To:     "Peter Zijlstra (Intel)" <peterz@...radead.org>
Cc:     "Ravi V. Shankar" <ravi.v.shankar@...el.com>,
        Ricardo Neri <ricardo.neri@...el.com>,
        Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>,
        Ben Segall <bsegall@...gle.com>,
        Caleb Callaway <caleb.callaway@...el.com>,
        Chen Yu <yu.c.chen@...el.com>,
        Daniel Bristot de Oliveira <bristot@...hat.com>,
        Dietmar Eggemann <dietmar.eggemann@....com>,
        Len Brown <len.brown@...el.com>, Mel Gorman <mgorman@...e.de>,
        Steven Rostedt <rostedt@...dmis.org>,
        "Tim C . Chen" <tim.c.chen@...el.com>,
        Valentin Schneider <vschneid@...hat.com>,
        Vincent Guittot <vincent.guittot@...aro.org>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] x86/sched: Restore the SD_ASYM_PACKING flag in the DIE domain

Commit 8f2d6c41e5a6 ("x86/sched: Rewrite topology setup") dropped the
SD_ASYM_PACKING flag in the DIE domain added in commit 044f0e27dec6
("x86/sched: Add the SD_ASYM_PACKING flag to the die domain of hybrid
processors"). Restore it on hybrid processors.

The die-level domain does not depend on any build configuration and now
x86_sched_itmt_flags() is always needed. Remove the build dependency on
CONFIG_SCHED_[SMT|CLUSTER|MC].

Cc: Ben Segall <bsegall@...gle.com>
Cc: Caleb Callaway <caleb.callaway@...el.com>
Cc: Chen Yu <yu.c.chen@...el.com>
Cc: Daniel Bristot de Oliveira <bristot@...hat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@....com>
Cc: Len Brown <len.brown@...el.com>
Cc: Mel Gorman <mgorman@...e.de>
Cc: Steven Rostedt <rostedt@...dmis.org>
Cc: Tim C. Chen <tim.c.chen@...el.com>
Cc: Valentin Schneider <vschneid@...hat.com>
Cc: Vincent Guittot <vincent.guittot@...aro.org>
Cc: x86@...nel.org
Cc: linux-kernel@...r.kernel.org
Fixes: 8f2d6c41e5a6 ("x86/sched: Rewrite topology setup")
Reviewed-by: Chen Yu <yu.c.chen@...el.com>
Tested-by: Caleb Callaway <caleb.callaway@...el.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
---
 arch/x86/kernel/smpboot.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index d7667a29acf3..944008c72754 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -579,7 +579,6 @@ static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
 }
 
 
-#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_CLUSTER) || defined(CONFIG_SCHED_MC)
 static inline int x86_sched_itmt_flags(void)
 {
 	return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
@@ -603,7 +602,12 @@ static int x86_cluster_flags(void)
 	return cpu_cluster_flags() | x86_sched_itmt_flags();
 }
 #endif
-#endif
+
+static int x86_die_flags(void)
+{
+	return cpu_feature_enabled(X86_FEATURE_HYBRID_CPU) ?
+	       x86_sched_itmt_flags() : 0;
+}
 
 /*
  * Set if a package/die has multiple NUMA nodes inside.
@@ -640,7 +644,7 @@ static void __init build_sched_topology(void)
 	 */
 	if (!x86_has_numa_in_package) {
 		x86_topology[i++] = (struct sched_domain_topology_level){
-			cpu_cpu_mask, SD_INIT_NAME(DIE)
+			cpu_cpu_mask, x86_die_flags, SD_INIT_NAME(DIE)
 		};
 	}
 
-- 
2.25.1