Currently, smp_fill_in_cpu_possible_map() unncessarily iterates
over all cpus to update possible/present cpumask based on nr_cpu_ids.
nr_cpus can be supported if nr_cpu_ids is checked instead of NR_CPUS
during MD parsing as well and saves some tiny boot time as well.
Update possible/present masks during MD parsing based on nr_cpu_ids.
Signed-off-by: Atish Patra <atish.patra@xxxxxxxxxx>
Reviewed-by: Anthony Yznaga <anthony.yznaga@xxxxxxxxxx>
---
arch/sparc/include/asm/smp_64.h | 2 --
arch/sparc/kernel/mdesc.c | 16 ++++++++--------
arch/sparc/kernel/prom_64.c | 16 ++++++++++++----
arch/sparc/kernel/setup_64.c | 1 -
arch/sparc/kernel/smp_64.c | 14 --------------
5 files changed, 20 insertions(+), 29 deletions(-)
diff --git a/arch/sparc/include/asm/smp_64.h b/arch/sparc/include/asm/smp_64.h
index ce2233f..26d9e77 100644
--- a/arch/sparc/include/asm/smp_64.h
+++ b/arch/sparc/include/asm/smp_64.h
@@ -43,7 +43,6 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask);
int hard_smp_processor_id(void);
#define raw_smp_processor_id() (current_thread_info()->cpu)
-void smp_fill_in_cpu_possible_map(void);
void smp_fill_in_sib_core_maps(void);
void cpu_play_dead(void);
@@ -73,7 +72,6 @@ void __cpu_die(unsigned int cpu);
#define smp_fill_in_sib_core_maps() do { } while (0)
#define smp_fetch_global_regs() do { } while (0)
#define smp_fetch_global_pmu() do { } while (0)
-#define smp_fill_in_cpu_possible_map() do { } while (0)
#endif /* !(CONFIG_SMP) */
diff --git a/arch/sparc/kernel/mdesc.c b/arch/sparc/kernel/mdesc.c
index 1122886..51f5e73 100644
--- a/arch/sparc/kernel/mdesc.c
+++ b/arch/sparc/kernel/mdesc.c
@@ -558,10 +558,10 @@ static void __init report_platform_properties(void)
if (v) {
max_cpu = *v;
- if (max_cpu > NR_CPUS)
- max_cpu = NR_CPUS;
+ if (max_cpu > nr_cpu_ids)
+ max_cpu = nr_cpu_ids;
} else {
- max_cpu = NR_CPUS;
+ max_cpu = nr_cpu_ids;
}
for (i = 0; i < max_cpu; i++)
set_cpu_possible(i, true);
@@ -770,7 +770,7 @@ static void mark_proc_ids(struct mdesc_handle *hp, u64 mp, int proc_id)
continue;
id = mdesc_get_property(hp, t, "id", NULL);
- if (*id < NR_CPUS)
+ if (*id < nr_cpu_ids)
cpu_data(*id).proc_id = proc_id;
}
}
@@ -861,12 +861,12 @@ static void *mdesc_iterate_over_cpus(void *(*func)(struct mdesc_handle *, u64, i
int cpuid = *id;
#ifdef CONFIG_SMP
- if (cpuid >= NR_CPUS) {
- printk(KERN_WARNING "Ignoring CPU %d which is "
- ">= NR_CPUS (%d)\n",
- cpuid, NR_CPUS);
+ if (cpuid >= nr_cpu_ids) {
+ pr_warn("Ignoring CPU %d which is >= nr_cpu_ids (%d)\n",
+ cpuid, nr_cpu_ids);
continue;
}
+
if (!cpumask_test_cpu(cpuid, mask))
continue;
#endif
diff --git a/arch/sparc/kernel/prom_64.c b/arch/sparc/kernel/prom_64.c
index 20cc5d8..34775f7 100644
--- a/arch/sparc/kernel/prom_64.c
+++ b/arch/sparc/kernel/prom_64.c
@@ -448,10 +448,9 @@ static void *of_iterate_over_cpus(void *(*func)(struct device_node *, int, int),
prom_halt();
}
#ifdef CONFIG_SMP
- if (cpuid >= NR_CPUS) {
- printk(KERN_WARNING "Ignoring CPU %d which is "
- ">= NR_CPUS (%d)\n",
- cpuid, NR_CPUS);
+ if (cpuid >= nr_cpu_ids) {
+ pr_warn("Ignoring CPU %d which is >= nr_cpu_ids (%d)\n",
+ cpuid, nr_cpu_ids);
continue;
}
#endif
@@ -491,6 +490,15 @@ void __init of_populate_present_mask(void)
ncpus_probed = 0;
of_iterate_over_cpus(record_one_cpu, 0);
+
+ /* This is a hack to accommodate the assumption in timer code that CPU0
+ * always exists and therefore timers can be assigned to CPU0 at static
+ * initialization time. Setting CPU0 in the possible mask ensures that
+ * the per-cpu timer data structures for CPU0 are properly initialized
+ * for use by such timers even when there is no CPU0 present.
+ */
+ if (!cpu_possible(0))
+ set_cpu_possible(0, true);
}
static void *fill_in_one_cpu(struct device_node *dp, int cpuid, int arg)
diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
index 6b7331d..9ce259a 100644
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -669,7 +669,6 @@ void __init setup_arch(char **cmdline_p)
paging_init();
init_sparc64_elf_hwcap();
- smp_fill_in_cpu_possible_map();
/*
* Once the OF device tree and MDESC have been setup and nr_cpus has
* been parsed, we know the list of possible cpus. Therefore we can
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
index d3035ba..8a6151a 100644
--- a/arch/sparc/kernel/smp_64.c
+++ b/arch/sparc/kernel/smp_64.c
@@ -1227,20 +1227,6 @@ void __init smp_setup_processor_id(void)
xcall_deliver_impl = hypervisor_xcall_deliver;
}
-void __init smp_fill_in_cpu_possible_map(void)
-{
- int possible_cpus = num_possible_cpus();
- int i;
-
- if (possible_cpus > nr_cpu_ids)
- possible_cpus = nr_cpu_ids;
-
- for (i = 0; i < possible_cpus; i++)
- set_cpu_possible(i, true);
- for (; i < NR_CPUS; i++)
- set_cpu_possible(i, false);
-}
-
void smp_fill_in_sib_core_maps(void)
{
unsigned int i;
--
1.7.1
--
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