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6462dd53a2
struct scx_iter_scx_dsq is defined as 6 u64's and scx_dsq_iter_kern was using 5 of them. We want to add two more u64 fields but it's better if we do so while staying within scx_iter_scx_dsq to maintain binary compatibility. The way scx_iter_scx_dsq_kern is laid out is rather inefficient - the node field takes up three u64's but only one bit of the last u64 is used. Turn the bool into u32 flags and only use the lower 16 bits freeing up 48 bits - 16 bits for flags, 32 bits for a u32 - for use by struct bpf_iter_scx_dsq_kern. This allows moving the dsq_seq and flags fields of bpf_iter_scx_dsq_kern into the cursor field reducing the struct size by a full u64. No behavior changes intended. Signed-off-by: Tejun Heo <tj@kernel.org>