This was noticed during the investigation of
http://git.kernel.org/tip/2a51fe083eba7f99cbda72f5ef90cdf2f4df882c
A note for reviewers on the cleanup in smp_init_package_map(): The
per_cpu variable x86_bios_cpu_apicid is initialized to BAD_APICID, and the
bitmaps are set to false by default so the code isn't necessary. The
pr_warn() can also be dropped as generic_processor_info() will do a
pr_warning() in the same situation.
P.
-----8<-----
After commit 1f12e32f4cd5 ("x86/topology: Create logical package id"),
topology_update_package_map() is called twice on a CPU. The first call is in
generic_processor_info(), which is called on all present cpus (found in either
mptable or ACPI MADT). The second call is in smp_init_package_map() which
is called later on in the init sequence.
Only a single call is necessary for the kernel to initialize the data
structures properly. This patch drops the later call in smp_init_package_map()
and moves smp_init_package_map() out of smp_store_boot_cpu_info().
Signed-off-by: Prarit Bhargava <pra...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: x...@kernel.org
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Len Brown <len.br...@intel.com>
Cc: Borislav Petkov <b...@suse.de>
Cc: Tim Chen <tim.c.c...@linux.intel.com>
Cc: Andi Kleen <a...@linux.intel.com>
Cc: Boris Ostrovsky <boris.ostrov...@oracle.com>
Cc: Jiri Olsa <jo...@redhat.com>
---
arch/x86/kernel/smpboot.c | 20 +++-----------------
1 file changed, 3 insertions(+), 17 deletions(-)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 951f093a96fe..0ff74f8bb5e9 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -271,7 +271,7 @@ int topology_update_package_map(unsigned int apicid,
unsigned int cpu)
if (!physical_package_map)
return 0;
- if (pkg >= max_physical_pkg_id)
+ if (!apic->apic_id_valid(apicid) || pkg >= max_physical_pkg_id)
return -EINVAL;
/* Set the logical package id */
@@ -310,7 +310,7 @@ int topology_phys_to_logical_pkg(unsigned int phys_pkg)
static void __init smp_init_package_map(void)
{
- unsigned int ncpus, cpu;
+ unsigned int ncpus;
size_t size;
/*
@@ -342,7 +342,6 @@ static void __init smp_init_package_map(void)
}
__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
- logical_packages = 0;
/*
* Possibly larger than what we need as the number of apic ids per
@@ -355,19 +354,6 @@ static void __init smp_init_package_map(void)
size = BITS_TO_LONGS(max_physical_pkg_id) * sizeof(unsigned long);
physical_package_map = kzalloc(size, GFP_KERNEL);
- for_each_present_cpu(cpu) {
- unsigned int apicid = apic->cpu_present_to_apicid(cpu);
-
- if (apicid == BAD_APICID || !apic->apic_id_valid(apicid))
- continue;
- if (!topology_update_package_map(apicid, cpu))
- continue;
- pr_warn("CPU %u APICId %x disabled\n", cpu, apicid);
- per_cpu(x86_bios_cpu_apicid, cpu) = BAD_APICID;
- set_cpu_possible(cpu, false);
- set_cpu_present(cpu, false);
- }
-
if (logical_packages > __max_logical_packages) {
pr_warn("Detected more packages (%u), then computed by BIOS
data (%u).\n",
logical_packages, __max_logical_packages);
@@ -385,7 +371,6 @@ void __init smp_store_boot_cpu_info(void)
*c = boot_cpu_data;
c->cpu_index = id;
- smp_init_package_map();
}
/*
@@ -1285,6 +1270,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
* Setup boot CPU information
*/
smp_store_boot_cpu_info(); /* Final full version of the data */
+ smp_init_package_map();
cpumask_copy(cpu_callin_mask, cpumask_of(0));
mb();
--
1.7.9.3
