!893 mitigatin cacheline false sharing
Merge Pull Request from: @zhangjialin11 In the test of execl, shell1 and shell8 of UnixBench, L3 false sharing occurs between rwsem_try_write_lock_unqueued() and filemap_map_pages(). The offset between address_space.host and address_space.i_mmap_rwsem is 48. It may occur L3 false sharing. Their offsets in struct ext4_inode_info is 696 and 744, so when the address of ext4_inode_info after L3 aligned, it may occur L3 false sharing in the following condition: [0x00 ~ 0x10] false sharing [0x18 ~ 0x40] no false sharing [0x48 ~ 0x80] false sharing Change the offset of 'vfs_inode' from 320 to 360 in ext4_inode_info and make the address of ext4_inode_info L3 aligned, so the offset of host and i_mmap_rwsem in ext4_inode_info is changed to 736 and 784, it can make them in different L3 to avoid false sharing. ./Run -c 96 -i 3 execl Before this patch: System Benchmarks Partial Index BASELINE RESULT INDEX Execl Throughput 43.0 24238.0 5636.8 ======== System Benchmarks Index Score (Partial Only) 5636.8 After this patch: System Benchmarks Partial Index BASELINE RESULT INDEX Execl Throughput 43.0 29363.7 6828.8 ======== System Benchmarks Index Score (Partial Only) 6828.8 Link:https://gitee.com/openeuler/kernel/pulls/893 Reviewed-by: zhangyi (F) <yi.zhang@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
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