irqbalance/irqbalance-use-num_online_cpus-instead-core_count.patch
2020-07-03 17:09:39 +08:00

228 lines
7.8 KiB
Diff

From 8799a564dc331732af431bad25a8744e043f8409 Mon Sep 17 00:00:00 2001
From: Yunfeng Ye <yeyunfeng@huawei.com>
Date: Mon, 4 Nov 2019 11:51:46 +0800
Subject: [PATCH 38/53] irqbalance: use num_online_cpus() instead core_count
The variable core_count is actually the number of online cpus, and
cpu_possible_map is unused, so change cpu_possible_map to cpu_online_map
and use num_online_cpus() instead of core_count.
In addition, remove cpu_possible_map and cpu_present_map, also its
associated macros, which there are unused.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
---
cpumask.h | 79 +-----------------------------------------------
cputree.c | 10 ++----
irqbalance.c | 2 +-
irqbalance.h | 1 -
procinterrupts.c | 2 +-
5 files changed, 6 insertions(+), 88 deletions(-)
diff --git a/cpumask.h b/cpumask.h
index 0774a88..5bebbeb 100644
--- a/cpumask.h
+++ b/cpumask.h
@@ -59,18 +59,10 @@
* for_each_cpu_mask(cpu, mask) for-loop cpu over mask
*
* int num_online_cpus() Number of online CPUs
- * int num_possible_cpus() Number of all possible CPUs
- * int num_present_cpus() Number of present CPUs
*
* int cpu_online(cpu) Is some cpu online?
- * int cpu_possible(cpu) Is some cpu possible?
- * int cpu_present(cpu) Is some cpu present (can schedule)?
*
- * int any_online_cpu(mask) First online cpu in mask
- *
- * for_each_possible_cpu(cpu) for-loop cpu over cpu_possible_map
* for_each_online_cpu(cpu) for-loop cpu over cpu_online_map
- * for_each_present_cpu(cpu) for-loop cpu over cpu_present_map
*
* Subtlety:
* 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway)
@@ -314,87 +306,18 @@ static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
#endif /* NR_CPUS */
/*
- * The following particular system cpumasks and operations manage
- * possible, present and online cpus. Each of them is a fixed size
- * bitmap of size NR_CPUS.
- *
- * #ifdef CONFIG_HOTPLUG_CPU
- * cpu_possible_map - has bit 'cpu' set iff cpu is populatable
- * cpu_present_map - has bit 'cpu' set iff cpu is populated
- * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
- * #else
- * cpu_possible_map - has bit 'cpu' set iff cpu is populated
- * cpu_present_map - copy of cpu_possible_map
- * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
- * #endif
- *
- * In either case, NR_CPUS is fixed at compile time, as the static
- * size of these bitmaps. The cpu_possible_map is fixed at boot
- * time, as the set of CPU id's that it is possible might ever
- * be plugged in at anytime during the life of that system boot.
- * The cpu_present_map is dynamic(*), representing which CPUs
- * are currently plugged in. And cpu_online_map is the dynamic
- * subset of cpu_present_map, indicating those CPUs available
- * for scheduling.
- *
- * If HOTPLUG is enabled, then cpu_possible_map is forced to have
- * all NR_CPUS bits set, otherwise it is just the set of CPUs that
- * ACPI reports present at boot.
- *
- * If HOTPLUG is enabled, then cpu_present_map varies dynamically,
- * depending on what ACPI reports as currently plugged in, otherwise
- * cpu_present_map is just a copy of cpu_possible_map.
- *
- * (*) Well, cpu_present_map is dynamic in the hotplug case. If not
- * hotplug, it's a copy of cpu_possible_map, hence fixed at boot.
- *
- * Subtleties:
- * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
- * assumption that their single CPU is online. The UP
- * cpu_{online,possible,present}_maps are placebos. Changing them
- * will have no useful affect on the following num_*_cpus()
- * and cpu_*() macros in the UP case. This ugliness is a UP
- * optimization - don't waste any instructions or memory references
- * asking if you're online or how many CPUs there are if there is
- * only one CPU.
- * 2) Most SMP arch's #define some of these maps to be some
- * other map specific to that arch. Therefore, the following
- * must be #define macros, not inlines. To see why, examine
- * the assembly code produced by the following. Note that
- * set1() writes phys_x_map, but set2() writes x_map:
- * int x_map, phys_x_map;
- * #define set1(a) x_map = a
- * inline void set2(int a) { x_map = a; }
- * #define x_map phys_x_map
- * main(){ set1(3); set2(5); }
+ * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
*/
-
-extern cpumask_t cpu_possible_map;
extern cpumask_t cpu_online_map;
-extern cpumask_t cpu_present_map;
#if NR_CPUS > 1
#define num_online_cpus() cpus_weight(cpu_online_map)
-#define num_possible_cpus() cpus_weight(cpu_possible_map)
-#define num_present_cpus() cpus_weight(cpu_present_map)
#define cpu_online(cpu) cpu_isset((cpu), cpu_online_map)
-#define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map)
-#define cpu_present(cpu) cpu_isset((cpu), cpu_present_map)
#else
#define num_online_cpus() 1
-#define num_possible_cpus() 1
-#define num_present_cpus() 1
#define cpu_online(cpu) ((cpu) == 0)
-#define cpu_possible(cpu) ((cpu) == 0)
-#define cpu_present(cpu) ((cpu) == 0)
#endif
-int highest_possible_processor_id(void);
-#define any_online_cpu(mask) __any_online_cpu(&(mask))
-int __any_online_cpu(const cpumask_t *mask);
-
-#define for_each_possible_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map)
#define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map)
-#define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)
#endif /* __LINUX_CPUMASK_H */
diff --git a/cputree.c b/cputree.c
index 69f4c6d..8178ba8 100644
--- a/cputree.c
+++ b/cputree.c
@@ -45,12 +45,11 @@ GList *cache_domains;
GList *packages;
int cache_domain_count;
-int core_count;
/* Users want to be able to keep interrupts away from some cpus; store these in a cpumask_t */
cpumask_t banned_cpus;
-cpumask_t cpu_possible_map;
+cpumask_t cpu_online_map;
/*
it's convenient to have the complement of banned_cpus available so that
@@ -284,7 +283,7 @@ static void do_one_cpu(char *path)
cpu->number = strtoul(&path[27], NULL, 10);
- cpu_set(cpu->number, cpu_possible_map);
+ cpu_set(cpu->number, cpu_online_map);
cpu_set(cpu->number, cpu->mask);
@@ -297,8 +296,6 @@ static void do_one_cpu(char *path)
/* if the cpu is on the banned list, just don't add it */
if (cpus_intersects(cpu->mask, banned_cpus)) {
free(cpu);
- /* even though we don't use the cpu we do need to count it */
- core_count++;
return;
}
@@ -383,7 +380,6 @@ static void do_one_cpu(char *path)
cpu->obj_type_list = &cpus;
cpus = g_list_append(cpus, cpu);
- core_count++;
}
static void dump_irq(struct irq_info *info, void *data)
@@ -537,7 +533,7 @@ void clear_cpu_tree(void)
g_list_free_full(cpus, free_cpu_topo);
cpus = NULL;
- core_count = 0;
+ cpus_clear(cpu_online_map);
}
static gint compare_cpus(gconstpointer a, gconstpointer b)
diff --git a/irqbalance.c b/irqbalance.c
index 619f51f..c9379ad 100644
--- a/irqbalance.c
+++ b/irqbalance.c
@@ -646,7 +646,7 @@ int main(int argc, char** argv)
/* On single core UP systems irqbalance obviously has no work to do */
- if (core_count<2) {
+ if (num_online_cpus() <= 1) {
char *msg = "Balancing is ineffective on systems with a "
"single cpu. Shutting down\n";
diff --git a/irqbalance.h b/irqbalance.h
index 61d7550..85fcbf2 100644
--- a/irqbalance.h
+++ b/irqbalance.h
@@ -31,7 +31,6 @@
#define NUMA_NO_NODE (-1)
-extern int core_count;
extern char *classes[];
extern void parse_cpu_tree(void);
diff --git a/procinterrupts.c b/procinterrupts.c
index 35d3be8..858b66b 100644
--- a/procinterrupts.c
+++ b/procinterrupts.c
@@ -303,7 +303,7 @@ void parse_proc_interrupts(void)
c=c2;
cpunr++;
}
- if (cpunr != core_count) {
+ if (cpunr != num_online_cpus()) {
need_rescan = 1;
break;
}
--
2.23.0