kernel-fxtec-pro1x/include/linux/node.h
David Hildenbrand 030d045dc0 mm/memory_hotplug: make unregister_memory_block_under_nodes() never fail
commit a31b264c2b415b29660da0bc2ba291a98629ce51 upstream.

We really don't want anything during memory hotunplug to fail.  We
always pass a valid memory block device, that check can go.  Avoid
allocating memory and eventually failing.  As we are always called under
lock, we can use a static piece of memory.  This avoids having to put
the structure onto the stack, having to guess about the stack size of
callers.

Patch inspired by a patch from Oscar Salvador.

In the future, there might be no need to iterate over nodes at all.
mem->nid should tell us exactly what to remove.  Memory block devices
with mixed nodes (added during boot) should properly fenced off and
never removed.

Link: http://lkml.kernel.org/r/20190527111152.16324-11-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jun Yao <yaojun8558363@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 16:43:26 +01:00

119 lines
3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/node.h - generic node definition
*
* This is mainly for topological representation. We define the
* basic 'struct node' here, which can be embedded in per-arch
* definitions of processors.
*
* Basic handling of the devices is done in drivers/base/node.c
* and system devices are handled in drivers/base/sys.c.
*
* Nodes are exported via driverfs in the class/node/devices/
* directory.
*/
#ifndef _LINUX_NODE_H_
#define _LINUX_NODE_H_
#include <linux/device.h>
#include <linux/cpumask.h>
#include <linux/workqueue.h>
struct node {
struct device dev;
#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
struct work_struct node_work;
#endif
};
struct memory_block;
extern struct node *node_devices[];
typedef void (*node_registration_func_t)(struct node *);
#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
extern int link_mem_sections(int nid, unsigned long start_pfn,
unsigned long end_pfn);
#else
static inline int link_mem_sections(int nid, unsigned long start_pfn,
unsigned long end_pfn)
{
return 0;
}
#endif
extern void unregister_node(struct node *node);
#ifdef CONFIG_NUMA
/* Core of the node registration - only memory hotplug should use this */
extern int __register_one_node(int nid);
/* Registers an online node */
static inline int register_one_node(int nid)
{
int error = 0;
if (node_online(nid)) {
struct pglist_data *pgdat = NODE_DATA(nid);
unsigned long start_pfn = pgdat->node_start_pfn;
unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
error = __register_one_node(nid);
if (error)
return error;
/* link memory sections under this node */
error = link_mem_sections(nid, start_pfn, end_pfn);
}
return error;
}
extern void unregister_one_node(int nid);
extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
extern int register_mem_sect_under_node(struct memory_block *mem_blk,
void *arg);
extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
#ifdef CONFIG_HUGETLBFS
extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
node_registration_func_t unregister);
#endif
#else
static inline int __register_one_node(int nid)
{
return 0;
}
static inline int register_one_node(int nid)
{
return 0;
}
static inline int unregister_one_node(int nid)
{
return 0;
}
static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
{
return 0;
}
static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
{
return 0;
}
static inline int register_mem_sect_under_node(struct memory_block *mem_blk,
void *arg)
{
return 0;
}
static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
{
}
static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
node_registration_func_t unreg)
{
}
#endif
#define to_node(device) container_of(device, struct node, dev)
#endif /* _LINUX_NODE_H_ */