Re: [PATCH v4 5/5] sched: rename SD_SHARE_PKG_RESOURCES to SD_SHARE_LLC

2024-02-08 Thread Ricardo Neri 
On Wed, Feb 07, 2024 at 11:58:40AM +0800, al...@kernel.org wrote:
> From: Alex Shi 
> 
> SD_CLUSTER shares the CPU resources like llc tags or l2 cache, that's
> easy confuse with SD_SHARE_PKG_RESOURCES. So let's specifical point
> what the latter shares: LLC. That would reduce some confusing.
> 
> Suggested-by: Valentin Schneider 
> Signed-off-by: Alex Shi 

FWIW, Reviewed-by: Ricardo Neri

Re: [PATCH v4 5/5] sched: rename SD_SHARE_PKG_RESOURCES to SD_SHARE_LLC

2024-02-08 Thread Valentin Schneider 
On 07/02/24 11:58, al...@kernel.org wrote:
> From: Alex Shi 
>
> SD_CLUSTER shares the CPU resources like llc tags or l2 cache, that's
> easy confuse with SD_SHARE_PKG_RESOURCES. So let's specifical point
> what the latter shares: LLC. That would reduce some confusing.
>
> Suggested-by: Valentin Schneider 
> Signed-off-by: Alex Shi 

AFAICT it's just missing the below replacement (I've stretched the comments
to go up to 80 chars while at it), otherwise LGTM.

Reviewed-by: Valentin Schneider 

---

diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index e877730219d38..99ea5986038ce 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -657,13 +657,13 @@ static void destroy_sched_domains(struct sched_domain *sd)
 }
 
 /*
- * Keep a special pointer to the highest sched_domain that has
- * SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this
- * allows us to avoid some pointer chasing select_idle_sibling().
+ * Keep a special pointer to the highest sched_domain that has SD_SHARE_LLC set
+ * (Last Level Cache Domain) for this allows us to avoid some pointer chasing
+ * select_idle_sibling().
  *
- * Also keep a unique ID per domain (we use the first CPU number in
- * the cpumask of the domain), this allows us to quickly tell if
- * two CPUs are in the same cache domain, see cpus_share_cache().
+ * Also keep a unique ID per domain (we use the first CPU number in the cpumask
+ * of the domain), this allows us to quickly tell if two CPUs are in the same
+ * cache domain, see cpus_share_cache().
  */
 DEFINE_PER_CPU(struct sched_domain __rcu *, sd_llc);
 DEFINE_PER_CPU(int, sd_llc_size);

[PATCH v4 5/5] sched: rename SD_SHARE_PKG_RESOURCES to SD_SHARE_LLC

2024-02-06 Thread alexs 
From: Alex Shi 

SD_CLUSTER shares the CPU resources like llc tags or l2 cache, that's
easy confuse with SD_SHARE_PKG_RESOURCES. So let's specifical point
what the latter shares: LLC. That would reduce some confusing.

Suggested-by: Valentin Schneider 
Signed-off-by: Alex Shi 
To: linux-ker...@vger.kernel.org
To: linuxppc-dev@lists.ozlabs.org
To: Miaohe Lin 
To: Barry Song 
To: Mark Rutland 
To: Frederic Weisbecker 
To: Daniel Bristot de Oliveira 
To: Ben Segall 
To: Steven Rostedt 
To: Dietmar Eggemann 
To: Juri Lelli 
To: Ingo Molnar 
To: "Naveen N. Rao" 
To: "Aneesh Kumar K.V" 
To: Christophe Leroy 
Cc: "Gautham R. Shenoy" 
Cc: Yicong Yang 
Cc: Ricardo Neri 
Cc: Josh Poimboeuf 
Cc: Srikar Dronamraju 
Cc: Valentin Schneider 
Cc: Nicholas Piggin 
Cc: Michael Ellerman 
---
 arch/powerpc/kernel/smp.c  |  6 +++---
 include/linux/sched/sd_flags.h |  4 ++--
 include/linux/sched/topology.h |  6 +++---
 kernel/sched/fair.c|  2 +-
 kernel/sched/topology.c| 16 
 5 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 693334c20d07..a60e4139214b 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -984,7 +984,7 @@ static bool shared_caches __ro_after_init;
 /* cpumask of CPUs with asymmetric SMT dependency */
 static int powerpc_smt_flags(void)
 {
-   int flags = SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
+   int flags = SD_SHARE_CPUCAPACITY | SD_SHARE_LLC;
 
if (cpu_has_feature(CPU_FTR_ASYM_SMT)) {
printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n");
@@ -1010,9 +1010,9 @@ static __ro_after_init 
DEFINE_STATIC_KEY_FALSE(splpar_asym_pack);
 static int powerpc_shared_cache_flags(void)
 {
if (static_branch_unlikely(_asym_pack))
-   return SD_SHARE_PKG_RESOURCES | SD_ASYM_PACKING;
+   return SD_SHARE_LLC | SD_ASYM_PACKING;
 
-   return SD_SHARE_PKG_RESOURCES;
+   return SD_SHARE_LLC;
 }
 
 static int powerpc_shared_proc_flags(void)
diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h
index a8b28647aafc..b04a5d04dee9 100644
--- a/include/linux/sched/sd_flags.h
+++ b/include/linux/sched/sd_flags.h
@@ -117,13 +117,13 @@ SD_FLAG(SD_SHARE_CPUCAPACITY, SDF_SHARED_CHILD | 
SDF_NEEDS_GROUPS)
 SD_FLAG(SD_CLUSTER, SDF_NEEDS_GROUPS)
 
 /*
- * Domain members share CPU package resources (i.e. caches)
+ * Domain members share CPU Last Level Caches
  *
  * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share
  *   the same cache(s).
  * NEEDS_GROUPS: Caches are shared between groups.
  */
-SD_FLAG(SD_SHARE_PKG_RESOURCES, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS)
+SD_FLAG(SD_SHARE_LLC, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS)
 
 /*
  * Only a single load balancing instance
diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index a6e04b4a21d7..191b122158fb 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -38,21 +38,21 @@ extern const struct sd_flag_debug sd_flag_debug[];
 #ifdef CONFIG_SCHED_SMT
 static inline int cpu_smt_flags(void)
 {
-   return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
+   return SD_SHARE_CPUCAPACITY | SD_SHARE_LLC;
 }
 #endif
 
 #ifdef CONFIG_SCHED_CLUSTER
 static inline int cpu_cluster_flags(void)
 {
-   return SD_CLUSTER | SD_SHARE_PKG_RESOURCES;
+   return SD_CLUSTER | SD_SHARE_LLC;
 }
 #endif
 
 #ifdef CONFIG_SCHED_MC
 static inline int cpu_core_flags(void)
 {
-   return SD_SHARE_PKG_RESOURCES;
+   return SD_SHARE_LLC;
 }
 #endif
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 10ae28e1c088..188597640b1f 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10695,7 +10695,7 @@ static inline void calculate_imbalance(struct lb_env 
*env, struct sd_lb_stats *s
 */
if (local->group_type == group_has_spare) {
if ((busiest->group_type > group_fully_busy) &&
-   !(env->sd->flags & SD_SHARE_PKG_RESOURCES)) {
+   !(env->sd->flags & SD_SHARE_LLC)) {
/*
 * If busiest is overloaded, try to fill spare
 * capacity. This might end up creating spare capacity
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 0b33f7b05d21..e877730219d3 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -684,7 +684,7 @@ static void update_top_cache_domain(int cpu)
int id = cpu;
int size = 1;
 
-   sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES);
+   sd = highest_flag_domain(cpu, SD_SHARE_LLC);
if (sd) {
id = cpumask_first(sched_domain_span(sd));
size = cpumask_weight(sched_domain_span(sd));
@@ -1554,7 +1554,7 @@ static struct cpumask 
***sched_domains_numa_masks;
  * function. For details, see