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x86/acpi: Introduce persistent storage for cpuid <-> apicid mapping

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The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that,
when node online/offline happens, cache based on cpuid <-> nodeid mapping such as
wq_numa_possible_cpumask will not cause any problem.
It contains 4 steps:
1. Enable apic registeration flow to handle both enabled and disabled cpus.
2. Introduce a new array storing all possible cpuid <-> apicid mapping.
3. Enable _MAT and MADT relative apis to return non-present or disabled cpus' apicid.
4. Establish all possible cpuid <-> nodeid mapping.

This patch finishes step 2.

In this patch, we introduce a new static array named cpuid_to_apicid[],
which is large enough to store info for all possible cpus.

And then, we modify the cpuid calculation. In generic_processor_info(),
it simply finds the next unused cpuid. And it is also why the cpuid <-> nodeid
mapping changes with node hotplug.

After this patch, we find the next unused cpuid, map it to an apicid,
and store the mapping in cpuid_to_apicid[], so that cpuid <-> apicid
mapping will be persistent.

And finally we will use this array to make cpuid <-> nodeid persistent.

cpuid <-> apicid mapping is established at local apic registeration time.
But non-present or disabled cpus are ignored.

In this patch, we establish all possible cpuid <-> apicid mapping when
registering local apic.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-4-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Gu Zheng 2016-08-25 16:35:16 +08:00 committed by Thomas Gleixner
parent f7c28833c2
commit 8f54969dc8
3 changed files with 59 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/x86/include/asm/mpspec.h
View File

@ -86,6 +86,7 @@ static inline void early_reserve_e820_mpc_new(void) { }
#endif
int generic_processor_info(int apicid, int version);
int __generic_processor_info(int apicid, int version, bool enabled);
#define PHYSID_ARRAY_SIZE BITS_TO_LONGS(MAX_LOCAL_APIC)

7
arch/x86/kernel/acpi/boot.c
View File

@ -176,15 +176,10 @@ static int acpi_register_lapic(int id, u32 acpiid, u8 enabled)
return -EINVAL;
}
if (!enabled) {
++disabled_cpus;
return -EINVAL;
}
if (boot_cpu_physical_apicid != -1U)
ver = boot_cpu_apic_version;
cpu = generic_processor_info(id, ver);
cpu = __generic_processor_info(id, ver, enabled);
if (cpu >= 0)
early_per_cpu(x86_cpu_to_acpiid, cpu) = acpiid;

60
arch/x86/kernel/apic/apic.c
View File

@ -2021,7 +2021,53 @@ void disconnect_bsp_APIC(int virt_wire_setup)
apic_write(APIC_LVT1, value);
}
static int __generic_processor_info(int apicid, int version, bool enabled)
/*
* The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
* contiguously, it equals to current allocated max logical CPU ID plus 1.
* All allocated CPU ID should be in [0, nr_logical_cpuidi), so the maximum of
* nr_logical_cpuids is nr_cpu_ids.
*
* NOTE: Reserve 0 for BSP.
*/
static int nr_logical_cpuids = 1;
/*
* Used to store mapping between logical CPU IDs and APIC IDs.
*/
static int cpuid_to_apicid[] = {
[0 ... NR_CPUS - 1] = -1,
};
/*
* Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
* and cpuid_to_apicid[] synchronized.
*/
static int allocate_logical_cpuid(int apicid)
{
int i;
/*
* cpuid <-> apicid mapping is persistent, so when a cpu is up,
* check if the kernel has allocated a cpuid for it.
*/
for (i = 0; i < nr_logical_cpuids; i++) {
if (cpuid_to_apicid[i] == apicid)
return i;
}
/* Allocate a new cpuid. */
if (nr_logical_cpuids >= nr_cpu_ids) {
WARN_ONCE(1, "Only %d processors supported."
"Processor %d/0x%x and the rest are ignored.\n",
nr_cpu_ids - 1, nr_logical_cpuids, apicid);
return -1;
}
cpuid_to_apicid[nr_logical_cpuids] = apicid;
return nr_logical_cpuids++;
}
int __generic_processor_info(int apicid, int version, bool enabled)
{
int cpu, max = nr_cpu_ids;
bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
@ -2096,8 +2142,16 @@ static int __generic_processor_info(int apicid, int version, bool enabled)
* for BSP.
*/
cpu = 0;
} else
cpu = cpumask_next_zero(-1, cpu_present_mask);
/* Logical cpuid 0 is reserved for BSP. */
cpuid_to_apicid[0] = apicid;
} else {
cpu = allocate_logical_cpuid(apicid);
if (cpu < 0) {
disabled_cpus++;
return -EINVAL;
}
}
/*
* This can happen on physical hotplug. The sanity check at boot time