From 0d6526f82c3cdefcca47f73f5fc08dc6f335eac6 Mon Sep 17 00:00:00 2001 From: Tim Chen Date: Mon, 21 Sep 2026 17:37:22 -0700 Subject: sched/cache: Keep nr_pref_llc_running in the runnable domain, to fix LLC mis-scheduling bug alb_break_llc() decides whether to break LLC preference during active load balance. It does so by testing that every runnable fair task on the source rq prefers its LLC: env->src_rq->nr_pref_llc_running == env->src_rq->cfs.h_nr_runnable But the two counters cover different sets. nr_pref_llc_running is updated in account_llc_enqueue()/account_llc_dequeue(), next to cfs_rq->nr_queued, so it follows queued tasks. h_nr_runnable is updated in set_delayed()/ clear_delayed() and drops delay-dequeued tasks. So under DELAY_DEQUEUE, a preferring task that goes to sleep stays counted in nr_pref_llc_running while h_nr_runnable falls. The equality then breaks, alb_break_llc() returns false, and active balance is free to pull a task off its preferred LLC. Active balance only moves runnable tasks, and this is the only LLC check it consults: once the stopper runs, LBF_ACTIVE_LB skips the per-task test in can_migrate_task(). The runnable set is the one we want. Fix it on the counter side. A task should be counted in nr_pref_llc_running exactly while it is both queued on its preferred LLC (pref_llc_queued) and runnable (!sched_delayed). Define that membership once in task_pref_llc_runnable(), and adjust the counter only through pref_llc_running_inc()/pref_llc_running_dec() from the four sites that change either input: account_llc_enqueue(), account_llc_dequeue(), set_delayed() and clear_delayed(). Gating every update on the same predicate keeps the delay, wake and dequeue paths from double-counting or underflowing; see the comments at those sites for the ordering. nr_llc_running and sd->llc_counts are not touched and stay on queued semantics. Fixes: 714059f79ff0 ("sched/cache: Handle moving single tasks to/from their preferred LLC") Closes: https://lore.kernel.org/lkml/20260827135000.735138-1-zhanxusheng@xiaomi.com/ Reported-by: Zhan Xusheng Suggested-by: Chen Yu Signed-off-by: Tim Chen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Kayra Cizmeci Cc: # v7.2.x Link: https://patch.msgid.link/06af61afedac32e6477f57feb4d658f6c411c3af.1790035273.git.tim.c.chen@linux.intel.com --- crypto/aegis.h | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 crypto/aegis.h (limited to 'crypto/aegis.h') diff --git a/crypto/aegis.h b/crypto/aegis.h new file mode 100644 index 000000000..ffcf8e85e --- /dev/null +++ b/crypto/aegis.h @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * AEGIS common definitions + * + * Copyright (c) 2018 Ondrej Mosnacek + * Copyright (c) 2018 Red Hat, Inc. All rights reserved. + */ + +#ifndef _CRYPTO_AEGIS_H +#define _CRYPTO_AEGIS_H + +#include +#include +#include + +#define AEGIS_BLOCK_SIZE 16 + +union aegis_block { + __le64 words64[AEGIS_BLOCK_SIZE / sizeof(__le64)]; + __le32 words32[AEGIS_BLOCK_SIZE / sizeof(__le32)]; + u8 bytes[AEGIS_BLOCK_SIZE]; +}; + +struct aegis_state; + +extern int aegis128_have_aes_insn; + +#define AEGIS_BLOCK_ALIGN (__alignof__(union aegis_block)) +#define AEGIS_ALIGNED(p) IS_ALIGNED((uintptr_t)p, AEGIS_BLOCK_ALIGN) + +bool crypto_aegis128_have_simd(void); +void crypto_aegis128_update_simd(struct aegis_state *state, const void *msg); +void crypto_aegis128_init_simd(struct aegis_state *state, + const union aegis_block *key, + const u8 *iv); +void crypto_aegis128_encrypt_chunk_simd(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size); +void crypto_aegis128_decrypt_chunk_simd(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size); +int crypto_aegis128_final_simd(struct aegis_state *state, + union aegis_block *tag_xor, + unsigned int assoclen, + unsigned int cryptlen, + unsigned int authsize); + +static __always_inline void crypto_aegis_block_xor(union aegis_block *dst, + const union aegis_block *src) +{ + dst->words64[0] ^= src->words64[0]; + dst->words64[1] ^= src->words64[1]; +} + +static __always_inline void crypto_aegis_block_and(union aegis_block *dst, + const union aegis_block *src) +{ + dst->words64[0] &= src->words64[0]; + dst->words64[1] &= src->words64[1]; +} + +static __always_inline void crypto_aegis_aesenc(union aegis_block *dst, + const union aegis_block *src, + const union aegis_block *key) +{ + const u8 *s = src->bytes; + const u32 *t = aes_enc_tab; + u32 d0, d1, d2, d3; + + d0 = t[s[ 0]] ^ rol32(t[s[ 5]], 8) ^ rol32(t[s[10]], 16) ^ rol32(t[s[15]], 24); + d1 = t[s[ 4]] ^ rol32(t[s[ 9]], 8) ^ rol32(t[s[14]], 16) ^ rol32(t[s[ 3]], 24); + d2 = t[s[ 8]] ^ rol32(t[s[13]], 8) ^ rol32(t[s[ 2]], 16) ^ rol32(t[s[ 7]], 24); + d3 = t[s[12]] ^ rol32(t[s[ 1]], 8) ^ rol32(t[s[ 6]], 16) ^ rol32(t[s[11]], 24); + + dst->words32[0] = cpu_to_le32(d0) ^ key->words32[0]; + dst->words32[1] = cpu_to_le32(d1) ^ key->words32[1]; + dst->words32[2] = cpu_to_le32(d2) ^ key->words32[2]; + dst->words32[3] = cpu_to_le32(d3) ^ key->words32[3]; +} + +#endif /* _CRYPTO_AEGIS_H */ -- cgit v1.3.1