在 2022/6/7 14:43, Anshuman Khandual 写道: > Hello Zhou, > > On 5/27/22 14:48, Zhou Guanghui wrote: >> In a system using HBM, a multi-bit ECC error occurs, and the BIOS >> will mark the corresponding area (for example, 2 MB) as unusable. >> When the system restarts next time, these areas are not reported >> or reported as EFI_UNUSABLE_MEMORY. Both cases lead to an increase >> in the number of memblocks, whereas EFI_UNUSABLE_MEMORY leads to a >> larger number of memblocks. >> >> For example, if the EFI_UNUSABLE_MEMORY type is reported: >> ... >> memory[0x92] [0x0000200834a00000-0x0000200835bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0 >> memory[0x93] [0x0000200835c00000-0x0000200835dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x94] [0x0000200835e00000-0x00002008367fffff], 0x0000000000a00000 bytes on node 7 flags: 0x0 >> memory[0x95] [0x0000200836800000-0x00002008369fffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x96] [0x0000200836a00000-0x0000200837bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0 >> memory[0x97] [0x0000200837c00000-0x0000200837dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x98] [0x0000200837e00000-0x000020087fffffff], 0x0000000048200000 bytes on node 7 flags: 0x0 >> memory[0x99] [0x0000200880000000-0x0000200bcfffffff], 0x0000000350000000 bytes on node 6 flags: 0x0 >> memory[0x9a] [0x0000200bd0000000-0x0000200bd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9b] [0x0000200bd0200000-0x0000200bd07fffff], 0x0000000000600000 bytes on node 6 flags: 0x0 >> memory[0x9c] [0x0000200bd0800000-0x0000200bd09fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9d] [0x0000200bd0a00000-0x0000200fcfffffff], 0x00000003ff600000 bytes on node 6 flags: 0x0 >> memory[0x9e] [0x0000200fd0000000-0x0000200fd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9f] [0x0000200fd0200000-0x0000200fffffffff], 0x000000002fe00000 bytes on node 6 flags: 0x0 >> ... > > Although this patch did not mention about a real world system requiring > this support, as been reported on the thread, Ampere Altra does seem to > get benefited. Regardless, it's always better to describe platform test > scenarios in more detail. > I encountered this scenario on Huawei Ascend ARM64 SoC. >> >> The EFI memory map is parsed to construct the memblock arrays before >> the memblock arrays can be resized. As the result, memory regions >> beyond INIT_MEMBLOCK_REGIONS are lost. >> >> Allow overriding memblock.memory array size with architecture defined >> INIT_MEMBLOCK_MEMORY_REGIONS and make arm64 to set >> INIT_MEMBLOCK_MEMORY_REGIONS to 1024 when CONFIG_EFI is enabled. > > Right, but first this needs to mention that INIT_MEMBLOCK_MEMORY_REGIONS > (new macro) is being added to replace INIT_MEMBLOCK_REGIONS, representing > max memory regions in the memblock. Platform override comes afterwards. > Add a paragraph before the description,like this? Add a new macro INIT_MEMBLOCK_MEMORY_REGTIONS to replace INIT_MEMBLOCK_REGTIONS to define the size of the static memblock.memory array. >> >> Signed-off-by: Zhou Guanghui <zhouguanghui1@xxxxxxxxxx> >> Acked-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> >> --- >> arch/arm64/include/asm/memory.h | 9 +++++++++ >> mm/memblock.c | 14 +++++++++----- >> 2 files changed, 18 insertions(+), 5 deletions(-) >> >> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h >> index 0af70d9abede..eda61c0389c4 100644 >> --- a/arch/arm64/include/asm/memory.h >> +++ b/arch/arm64/include/asm/memory.h >> @@ -364,6 +364,15 @@ void dump_mem_limit(void); >> # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) >> #endif >> >> +/* >> + * memory regions which marked with flag MEMBLOCK_NOMAP may divide a continuous >> + * memory block into multiple parts. As a result, the number of memory regions >> + * is large. >> + */ > > As mentioned in the previous version's thread, > > This comment needs be more specific about this increased static array size, being > applicable ONLY for MEMBLOCK_NOMAP regions on EFI system with EFI_UNUSABLE_MEMORY > tagging/flag support. > EFI_UNUSABLE_MEMORY is only one type of the MEMBLOCK_NOMAP region, as shown in the is_usable_memory function. However, However, I currently have too many memblocks due to this flag. >> +#ifdef CONFIG_EFI >> +#define INIT_MEMBLOCK_MEMORY_REGIONS 1024 > > Although 1024 seems adequate as compared to 128 memory regions in the memblock to > handle such error scenarios, but a co-relation with INIT_MEMBLOCK_REGIONS would > be preferred similar to when INIT_MEMBLOCK_RESERVED_REGIONS gets overridden. This > avoid a precedence when random numbers could get assigned in other archs later on. > > $git grep INIT_MEMBLOCK_RESERVED_REGIONS arch/ > arch/arm64/include/asm/memory.h:# define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) > arch/loongarch/include/asm/sparsemem.h:#define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS) > > Something like > > #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8) > I don't think this is necessary because INIT_MEMBLOCK_REGIONS is not configurable. The newly added INIT_MEMBLOCK_MEMORY_REGIONS macro is customized for each platform. > > - Anshuman > Thanks!
