Revert "resolve cherry-pick conflicts"

This reverts commit 1ea390b36bcde457224590055caecffa19a73127.
Revert "rwsem-spinlock: Implement writer lock-stealing for better scalability"

This reverts commit 107055c26766bdef022df1b295334671c1cf4796.
Revert "rwsem: Implement writer lock-stealing for better scalability"

This reverts commit 147fb607a7648cc2af11719caf0d9b85df1c508b.
Revert "softirq: reduce latencies"

This reverts commit 6476b3a1c712309522e5f1f039b9e1d17d9faaef.