On 10/07/2020 10:44, Zhenyu Ye wrote: > Add __TLBI_VADDR_RANGE macro and rewrite __flush_tlb_range(). > > When cpu supports TLBI feature, the minimum range granularity is > decided by 'scale', so we can not flush all pages by one instruction > in some cases. > > For example, when the pages = 0xe81a, let's start 'scale' from > maximum, and find right 'num' for each 'scale': > > 1. scale = 3, we can flush no pages because the minimum range is > 2^(5*3 + 1) = 0x10000. > 2. scale = 2, the minimum range is 2^(5*2 + 1) = 0x800, we can > flush 0xe800 pages this time, the num = 0xe800/0x800 - 1 = 0x1c. > Remaining pages is 0x1a; > 3. scale = 1, the minimum range is 2^(5*1 + 1) = 0x40, no page > can be flushed. > 4. scale = 0, we flush the remaining 0x1a pages, the num = > 0x1a/0x2 - 1 = 0xd. > > However, in most scenarios, the pages = 1 when flush_tlb_range() is > called. Start from scale = 3 or other proper value (such as scale = > ilog2(pages)), will incur extra overhead. > So increase 'scale' from 0 to maximum, the flush order is exactly > opposite to the example. > > Signed-off-by: Zhenyu Ye <yezhenyu2@xxxxxxxxxx> After this change I am seeing the following build errors ... /tmp/cckzq3FT.s: Assembler messages: /tmp/cckzq3FT.s:854: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:870: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:1095: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:1111: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:1964: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:1980: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:2286: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:2302: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x7' /tmp/cckzq3FT.s:4833: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x6' /tmp/cckzq3FT.s:4849: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x6' /tmp/cckzq3FT.s:5090: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x6' /tmp/cckzq3FT.s:5106: Error: unknown or missing operation name at operand 1 -- `tlbi rvae1is,x6' /tmp/cckzq3FT.s:874: Error: attempt to move .org backwards /tmp/cckzq3FT.s:1115: Error: attempt to move .org backwards /tmp/cckzq3FT.s:1984: Error: attempt to move .org backwards /tmp/cckzq3FT.s:2306: Error: attempt to move .org backwards /tmp/cckzq3FT.s:4853: Error: attempt to move .org backwards /tmp/cckzq3FT.s:5110: Error: attempt to move .org backwards scripts/Makefile.build:280: recipe for target 'arch/arm64/mm/hugetlbpage.o' failed make[3]: *** [arch/arm64/mm/hugetlbpage.o] Error 1 scripts/Makefile.build:497: recipe for target 'arch/arm64/mm' failed make[2]: *** [arch/arm64/mm] Error 2 Cheers Jon -- nvpublic
