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powerpc: Use nr_cpu_ids in initial paca allocation

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Now that we never set a cpu above nr_cpu_ids possible we can
limit our initial paca allocation to nr_cpu_ids.  We can then
clamp the number of cpus in platforms/iseries/setup.c.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Milton Miller 2011-05-10 19:28:52 +00:00 committed by Benjamin Herrenschmidt
parent 8657ae28dd
commit 2cd947f175
2 changed files with 11 additions and 11 deletions
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17
arch/powerpc/kernel/paca.c
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@ -7,7 +7,7 @@
* 2 of the License, or (at your option) any later version.
*/
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/module.h>
#include <linux/memblock.h>
@ -178,7 +178,7 @@ static int __initdata paca_size;
void __init allocate_pacas(void)
{
int nr_cpus, cpu, limit;
int cpu, limit;
/*
* We can't take SLB misses on the paca, and we want to access them
@ -190,23 +190,18 @@ void __init allocate_pacas(void)
if (firmware_has_feature(FW_FEATURE_ISERIES))
limit = min(limit, HvPagesToMap * HVPAGESIZE);
nr_cpus = NR_CPUS;
/* On iSeries we know we can never have more than 64 cpus */
if (firmware_has_feature(FW_FEATURE_ISERIES))
nr_cpus = min(64, nr_cpus);
paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpus);
paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids);
paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit));
memset(paca, 0, paca_size);
printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n",
paca_size, nr_cpus, paca);
paca_size, nr_cpu_ids, paca);
allocate_lppacas(nr_cpus, limit);
allocate_lppacas(nr_cpu_ids, limit);
/* Can't use for_each_*_cpu, as they aren't functional yet */
for (cpu = 0; cpu < nr_cpus; cpu++)
for (cpu = 0; cpu < nr_cpu_ids; cpu++)
initialise_paca(&paca[cpu], cpu);
}

5
arch/powerpc/platforms/iseries/setup.c
View file

@ -685,6 +685,11 @@ void * __init iSeries_early_setup(void)
powerpc_firmware_features |= FW_FEATURE_ISERIES;
powerpc_firmware_features |= FW_FEATURE_LPAR;
#ifdef CONFIG_SMP
/* On iSeries we know we can never have more than 64 cpus */
nr_cpu_ids = max(nr_cpu_ids, 64);
#endif
iSeries_fixup_klimit();
/*