Re: [PATCH v3 02/26] MIPS: sgi-ip27: make NODE_DATA() the same as on all other architectures
From: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Date: 2024-08-01 17:44:15
Also in:
linux-acpi, linux-arch, linux-arm-kernel, linux-cxl, linux-devicetree, linux-doc, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, lkml, loongarch, nvdimm, sparclinux
On Thu, 1 Aug 2024 09:08:02 +0300 Mike Rapoport [off-list ref] wrote:
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org> sgi-ip27 is the only system that defines NODE_DATA() differently than the rest of NUMA machines. Add node_data array of struct pglist pointers that will point to __node_data[node]->pglist and redefine NODE_DATA() to use node_data array. This will allow pulling declaration of node_data to the generic mm code in the next commit. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
After staring for a while at the use made of the other part of the __node_data I think what you have in this an the next two patches is fine. I'm far from convinced it was correct before though as arch_refresh_node_data() called on offline nodes in free_area_init() would have replaced __node_data with an allocation of size pg_data_t but the hub_data(), visible below, is after that. Maybe hub_data() as never called for offline nodes, but I couldn't establish that. After these patches the arch_refresh_node_data() generic version will only be replacing the pointer in node_data leaving the hub_data where it was in the first place and thus is fine. So with that in mind (and it could be completely wrong ;) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
quoted hunk ↗ jump to hunk
--- arch/mips/include/asm/mach-ip27/mmzone.h | 5 ++++- arch/mips/sgi-ip27/ip27-memory.c | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-)diff --git a/arch/mips/include/asm/mach-ip27/mmzone.h b/arch/mips/include/asm/mach-ip27/mmzone.h index 08c36e50a860..629c3f290203 100644 --- a/arch/mips/include/asm/mach-ip27/mmzone.h +++ b/arch/mips/include/asm/mach-ip27/mmzone.h@@ -22,7 +22,10 @@ struct node_data { extern struct node_data *__node_data[]; -#define NODE_DATA(n) (&__node_data[(n)]->pglist) #define hub_data(n) (&__node_data[(n)]->hub) +extern struct pglist_data *node_data[]; + +#define NODE_DATA(nid) (node_data[nid]) + #endif /* _ASM_MACH_MMZONE_H */diff --git a/arch/mips/sgi-ip27/ip27-memory.c b/arch/mips/sgi-ip27/ip27-memory.c index b8ca94cfb4fe..c30ef6958b97 100644 --- a/arch/mips/sgi-ip27/ip27-memory.c +++ b/arch/mips/sgi-ip27/ip27-memory.c@@ -34,8 +34,10 @@ #define SLOT_PFNSHIFT (SLOT_SHIFT - PAGE_SHIFT) #define PFN_NASIDSHFT (NASID_SHFT - PAGE_SHIFT) -struct node_data *__node_data[MAX_NUMNODES]; +struct pglist_data *node_data[MAX_NUMNODES]; +EXPORT_SYMBOL(node_data); +struct node_data *__node_data[MAX_NUMNODES]; EXPORT_SYMBOL(__node_data); static u64 gen_region_mask(void)@@ -361,6 +363,7 @@ static void __init node_mem_init(nasid_t node) */ __node_data[node] = __va(slot_freepfn << PAGE_SHIFT); memset(__node_data[node], 0, PAGE_SIZE); + node_data[node] = &__node_data[node]->pglist; NODE_DATA(node)->node_start_pfn = start_pfn; NODE_DATA(node)->node_spanned_pages = end_pfn - start_pfn;