linux_dsm_epyc7002/arch/powerpc/include/asm/topology.h
Nathan Fontenot 81b6132492 powerpc/pseries: Perform full re-add of CPU for topology update post-migration
On pseries systems, performing a partition migration can result in
altering the nodes a CPU is assigned to on the destination system. For
exampl, pre-migration on the source system CPUs are in node 1 and 3,
post-migration on the destination system CPUs are in nodes 2 and 3.

Handling the node change for a CPU can cause corruption in the slab
cache if we hit a timing where a CPUs node is changed while cache_reap()
is invoked. The corruption occurs because the slab cache code appears
to rely on the CPU and slab cache pages being on the same node.

The current dynamic updating of a CPUs node done in arch/powerpc/mm/numa.c
does not prevent us from hitting this scenario.

Changing the device tree property update notification handler that
recognizes an affinity change for a CPU to do a full DLPAR remove and
add of the CPU instead of dynamically changing its node resolves this
issue.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael W. Bringmann <mwb@linux.vnet.ibm.com>
Tested-by: Michael W. Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-30 23:28:56 +11:00

142 lines
3.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_TOPOLOGY_H
#define _ASM_POWERPC_TOPOLOGY_H
#ifdef __KERNEL__
struct device;
struct device_node;
#ifdef CONFIG_NUMA
/*
* If zone_reclaim_mode is enabled, a RECLAIM_DISTANCE of 10 will mean that
* all zones on all nodes will be eligible for zone_reclaim().
*/
#define RECLAIM_DISTANCE 10
#include <asm/mmzone.h>
#define cpumask_of_node(node) ((node) == -1 ? \
cpu_all_mask : \
node_to_cpumask_map[node])
struct pci_bus;
#ifdef CONFIG_PCI
extern int pcibus_to_node(struct pci_bus *bus);
#else
static inline int pcibus_to_node(struct pci_bus *bus)
{
return -1;
}
#endif
#define cpumask_of_pcibus(bus) (pcibus_to_node(bus) == -1 ? \
cpu_all_mask : \
cpumask_of_node(pcibus_to_node(bus)))
extern int __node_distance(int, int);
#define node_distance(a, b) __node_distance(a, b)
extern void __init dump_numa_cpu_topology(void);
extern int sysfs_add_device_to_node(struct device *dev, int nid);
extern void sysfs_remove_device_from_node(struct device *dev, int nid);
extern int numa_update_cpu_topology(bool cpus_locked);
static inline void update_numa_cpu_lookup_table(unsigned int cpu, int node)
{
numa_cpu_lookup_table[cpu] = node;
}
static inline int early_cpu_to_node(int cpu)
{
int nid;
nid = numa_cpu_lookup_table[cpu];
/*
* Fall back to node 0 if nid is unset (it should be, except bugs).
* This allows callers to safely do NODE_DATA(early_cpu_to_node(cpu)).
*/
return (nid < 0) ? 0 : nid;
}
#else
static inline int early_cpu_to_node(int cpu) { return 0; }
static inline void dump_numa_cpu_topology(void) {}
static inline int sysfs_add_device_to_node(struct device *dev, int nid)
{
return 0;
}
static inline void sysfs_remove_device_from_node(struct device *dev,
int nid)
{
}
static inline int numa_update_cpu_topology(bool cpus_locked)
{
return 0;
}
static inline void update_numa_cpu_lookup_table(unsigned int cpu, int node) {}
#endif /* CONFIG_NUMA */
#if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
extern int start_topology_update(void);
extern int stop_topology_update(void);
extern int prrn_is_enabled(void);
extern int find_and_online_cpu_nid(int cpu);
extern int timed_topology_update(int nsecs);
extern void __init shared_proc_topology_init(void);
#else
static inline int start_topology_update(void)
{
return 0;
}
static inline int stop_topology_update(void)
{
return 0;
}
static inline int prrn_is_enabled(void)
{
return 0;
}
static inline int find_and_online_cpu_nid(int cpu)
{
return 0;
}
static inline int timed_topology_update(int nsecs)
{
return 0;
}
#ifdef CONFIG_SMP
static inline void shared_proc_topology_init(void) {}
#endif
#endif /* CONFIG_NUMA && CONFIG_PPC_SPLPAR */
#include <asm-generic/topology.h>
#ifdef CONFIG_SMP
#include <asm/cputable.h>
#ifdef CONFIG_PPC64
#include <asm/smp.h>
#define topology_physical_package_id(cpu) (cpu_to_chip_id(cpu))
#define topology_sibling_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu))
#define topology_core_cpumask(cpu) (per_cpu(cpu_core_map, cpu))
#define topology_core_id(cpu) (cpu_to_core_id(cpu))
int dlpar_cpu_readd(int cpu);
#endif
#endif
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_TOPOLOGY_H */