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With default 512 cache nodes configuration, avc cache miss happens more often and occasionally leads to long time (>2ms) irqs off on both big and little cores, which decreases system real-time capability. Although we can expand avc nodes through /sys/fs/selinux/cache_threshold to mitigate long time irqs off, hash conflicts make the bucket average length longer because of the fixed size of cache slots, leading to avc_search_node() latency increase. This patch series aims to expand AVC nodes without significantly increasing avc_search_node() latency. This is v2 of the patch series, addressing feedback from v1. Changes since v1: - improve hash algorithm in avc_hash() - define avc_cache_slots as a static variable v1 discussion: https://lore.kernel.org/selinux/20250905100454.685866-1-zhanghongru@xiaomi.com/ -- Hongru Zhang (2): selinux: Make avc cache slot size configurable during boot selinux: improve bucket distribution uniformity of avc_hash() .../admin-guide/kernel-parameters.txt | 4 + security/selinux/avc.c | 82 ++++++++++++++----- 2 files changed, 64 insertions(+), 22 deletions(-) base-commit: 68e1e908cb7682db9fb7f79907f9352435a81c0f -- 2.43.0