powerpc: Set nr_cpu_ids early and use it to free PACAs

Ryan Grimm · ozbenh · commit c1854e00727f · 2011-04-05T16:22:11.000+10:00
Without this, "holes" in the CPU numbering can cause us to
free too many PACAs

Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
@@ -203,7 +203,7 @@ void __init free_unused_pacas(void)
 {
 	int new_size;
 
-	new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus());
+	new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids);
 
 	if (new_size >= paca_size)
 		return;
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
@@ -509,6 +509,9 @@ void __init smp_setup_cpu_maps(void)
 	 */
 	cpu_init_thread_core_maps(nthreads);
 
+	/* Now that possible cpus are set, set nr_cpu_ids for later use */
+	nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
+
 	free_unused_pacas();
 }
 #endif /* CONFIG_SMP */

Original file line number	Diff line number	Diff line change
`@@ -203,7 +203,7 @@ void __init free_unused_pacas(void)`
`203`	`203`	`{`
`204`	`204`	`int new_size;`
`205`	`205`
`206`		`- new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus());`
	`206`	`+ new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids);`
`207`	`207`
`208`	`208`	`if (new_size >= paca_size)`
`209`	`209`	`return;`
Original file line number	Diff line number	Diff line change
`@@ -509,6 +509,9 @@ void __init smp_setup_cpu_maps(void)`
`509`	`509`	`*/`
`510`	`510`	`cpu_init_thread_core_maps(nthreads);`
`511`	`511`
	`512`	`+ /* Now that possible cpus are set, set nr_cpu_ids for later use */`
	`513`	`+ nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;`
	`514`	`+`
`512`	`515`	`free_unused_pacas();`
`513`	`516`	`}`
`514`	`517`	`#endif /* CONFIG_SMP */`