2018-06-07 12:01:44

by Li RongQing

Subject: [PATCH] x86/acpi: fix the comments in acpi_parse_lapic

This should be permit to preallocate memory for all NR_CPUS

Signed-off-by: Li RongQing <[email protected]>
---
arch/x86/kernel/acpi/boot.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 3b20607d581b..8ae88605a5eb 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -223,7 +223,7 @@ acpi_parse_x2apic(struct acpi_subtable_header *header, const unsigned long end)
* We need to register disabled CPU as well to permit
* counting disabled CPUs. This allows us to size
* cpus_possible_map more accurately, to permit
- * to not preallocating memory for all NR_CPUS
+ * to preallocating memory for all NR_CPUS
* when we use CPU hotplug.
*/
if (!apic->apic_id_valid(apic_id)) {
@@ -260,7 +260,7 @@ acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end)
* We need to register disabled CPU as well to permit
* counting disabled CPUs. This allows us to size
* cpus_possible_map more accurately, to permit
- * to not preallocating memory for all NR_CPUS
+ * to preallocating memory for all NR_CPUS
* when we use CPU hotplug.
*/
acpi_register_lapic(processor->id, /* APIC ID */
--
2.16.2

2018-06-07 12:20:35

by Thomas Gleixner

Subject: Re: [PATCH] x86/acpi: fix the comments in acpi_parse_lapic

On Thu, 7 Jun 2018, Li RongQing wrote:

> This should be permit to preallocate memory for all NR_CPUS

No. The comment is correct. The whole magic is there to size
num_possible_cpus correctly so that we can avoid allocating for NR_CPUS
which is most of the time larger than num_possible_cpus.

Thanks,

tglx