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![]() Use a simple logical shift and increment to calculate the number of slots taken by the DMA segment boundary. At least GCC-13 is not able to optimize the expression, producing this horrible assembly code on x86: cmpq $-1, %rcx je .L364 addq $2048, %rcx shrq $11, %rcx movq %rcx, %r13 .L331: // rest of the function here... // after function epilogue and return: .L364: movabsq $9007199254740992, %r13 jmp .L331 After the optimization, the code looks more reasonable: shrq $11, %r11 leaq 1(%r11), %rbx Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> |
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.. | ||
coherent.c | ||
contiguous.c | ||
debug.c | ||
debug.h | ||
direct.c | ||
direct.h | ||
dummy.c | ||
Kconfig | ||
Makefile | ||
map_benchmark.c | ||
mapping.c | ||
ops_helpers.c | ||
pool.c | ||
remap.c | ||
swiotlb.c |