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 --- net/mac80211/debug.h | 249 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 249 insertions(+) create mode 100644 net/mac80211/debug.h (limited to 'net/mac80211/debug.h') diff --git a/net/mac80211/debug.h b/net/mac80211/debug.h new file mode 100644 index 000000000..ef7c1a68d --- /dev/null +++ b/net/mac80211/debug.h @@ -0,0 +1,249 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Portions + * Copyright (C) 2022 - 2025 Intel Corporation + */ +#ifndef __MAC80211_DEBUG_H +#define __MAC80211_DEBUG_H +#include +#include + +#ifdef CONFIG_MAC80211_OCB_DEBUG +#define MAC80211_OCB_DEBUG 1 +#else +#define MAC80211_OCB_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_IBSS_DEBUG +#define MAC80211_IBSS_DEBUG 1 +#else +#define MAC80211_IBSS_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_PS_DEBUG +#define MAC80211_PS_DEBUG 1 +#else +#define MAC80211_PS_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_HT_DEBUG +#define MAC80211_HT_DEBUG 1 +#else +#define MAC80211_HT_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MPL_DEBUG +#define MAC80211_MPL_DEBUG 1 +#else +#define MAC80211_MPL_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MPATH_DEBUG +#define MAC80211_MPATH_DEBUG 1 +#else +#define MAC80211_MPATH_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MHWMP_DEBUG +#define MAC80211_MHWMP_DEBUG 1 +#else +#define MAC80211_MHWMP_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MESH_SYNC_DEBUG +#define MAC80211_MESH_SYNC_DEBUG 1 +#else +#define MAC80211_MESH_SYNC_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MESH_CSA_DEBUG +#define MAC80211_MESH_CSA_DEBUG 1 +#else +#define MAC80211_MESH_CSA_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MESH_PS_DEBUG +#define MAC80211_MESH_PS_DEBUG 1 +#else +#define MAC80211_MESH_PS_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_TDLS_DEBUG +#define MAC80211_TDLS_DEBUG 1 +#else +#define MAC80211_TDLS_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_STA_DEBUG +#define MAC80211_STA_DEBUG 1 +#else +#define MAC80211_STA_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MLME_DEBUG +#define MAC80211_MLME_DEBUG 1 +#else +#define MAC80211_MLME_DEBUG 0 +#endif + +#ifdef CONFIG_MAC80211_MESSAGE_TRACING +void __sdata_info(const char *fmt, ...) __printf(1, 2); +void __sdata_dbg(bool print, const char *fmt, ...) __printf(2, 3); +void __sdata_err(const char *fmt, ...) __printf(1, 2); +void __wiphy_dbg(struct wiphy *wiphy, bool print, const char *fmt, ...) + __printf(3, 4); + +#define _sdata_info(sdata, fmt, ...) \ + __sdata_info("%s: " fmt, (sdata)->name, ##__VA_ARGS__) +#define _sdata_dbg(print, sdata, fmt, ...) \ + __sdata_dbg(print, "%s: " fmt, (sdata)->name, ##__VA_ARGS__) +#define _sdata_err(sdata, fmt, ...) \ + __sdata_err("%s: " fmt, (sdata)->name, ##__VA_ARGS__) +#define _wiphy_dbg(print, wiphy, fmt, ...) \ + __wiphy_dbg(wiphy, print, fmt, ##__VA_ARGS__) +#else +#define _sdata_info(sdata, fmt, ...) \ +do { \ + pr_info("%s: " fmt, \ + (sdata)->name, ##__VA_ARGS__); \ +} while (0) + +#define _sdata_dbg(print, sdata, fmt, ...) \ +do { \ + if (print) \ + pr_debug("%s: " fmt, \ + (sdata)->name, ##__VA_ARGS__); \ +} while (0) + +#define _sdata_err(sdata, fmt, ...) \ +do { \ + pr_err("%s: " fmt, \ + (sdata)->name, ##__VA_ARGS__); \ +} while (0) + +#define _wiphy_dbg(print, wiphy, fmt, ...) \ +do { \ + if (print) \ + wiphy_dbg((wiphy), fmt, ##__VA_ARGS__); \ +} while (0) +#endif + +#define sdata_info(sdata, fmt, ...) \ + _sdata_info(sdata, fmt, ##__VA_ARGS__) +#define sdata_err(sdata, fmt, ...) \ + _sdata_err(sdata, fmt, ##__VA_ARGS__) +#define sdata_dbg(sdata, fmt, ...) \ + _sdata_dbg(1, sdata, fmt, ##__VA_ARGS__) + +#define link_info(link, fmt, ...) \ + do { \ + if (ieee80211_vif_is_mld(&(link)->sdata->vif)) \ + _sdata_info((link)->sdata, "[link %d] " fmt, \ + (link)->link_id, \ + ##__VA_ARGS__); \ + else \ + _sdata_info((link)->sdata, fmt, ##__VA_ARGS__); \ + } while (0) +#define link_err(link, fmt, ...) \ + do { \ + if (ieee80211_vif_is_mld(&(link)->sdata->vif)) \ + _sdata_err((link)->sdata, "[link %d] " fmt, \ + (link)->link_id, \ + ##__VA_ARGS__); \ + else \ + _sdata_err((link)->sdata, fmt, ##__VA_ARGS__); \ + } while (0) +#define link_err_once(link, fmt, ...) \ + DO_ONCE_LITE(link_err, link, fmt, ##__VA_ARGS__) +#define link_id_info(sdata, link_id, fmt, ...) \ + do { \ + if (ieee80211_vif_is_mld(&sdata->vif)) \ + _sdata_info(sdata, "[link %d] " fmt, link_id, \ + ##__VA_ARGS__); \ + else \ + _sdata_info(sdata, fmt, ##__VA_ARGS__); \ + } while (0) +#define _link_id_dbg(print, sdata, link_id, fmt, ...) \ + do { \ + if (ieee80211_vif_is_mld(&(sdata)->vif)) \ + _sdata_dbg(print, sdata, "[link %d] " fmt, \ + link_id, ##__VA_ARGS__); \ + else \ + _sdata_dbg(print, sdata, fmt, ##__VA_ARGS__); \ + } while (0) +#define link_dbg(link, fmt, ...) \ + _link_id_dbg(1, (link)->sdata, (link)->link_id, \ + fmt, ##__VA_ARGS__) + +#define ht_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_HT_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define ht_dbg_ratelimited(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_HT_DEBUG && net_ratelimit(), \ + sdata, fmt, ##__VA_ARGS__) + +#define ocb_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_OCB_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define ibss_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_IBSS_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define ps_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_PS_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define ps_dbg_hw(hw, fmt, ...) \ + _wiphy_dbg(MAC80211_PS_DEBUG, \ + (hw)->wiphy, fmt, ##__VA_ARGS__) + +#define ps_dbg_ratelimited(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_PS_DEBUG && net_ratelimit(), \ + sdata, fmt, ##__VA_ARGS__) + +#define mpl_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MPL_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define mpath_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MPATH_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define mhwmp_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MHWMP_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define msync_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MESH_SYNC_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define mcsa_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MESH_CSA_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define mps_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MESH_PS_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define tdls_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_TDLS_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define sta_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_STA_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) + +#define mlme_dbg(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MLME_DEBUG, \ + sdata, fmt, ##__VA_ARGS__) +#define mlme_link_id_dbg(sdata, link_id, fmt, ...) \ + _link_id_dbg(MAC80211_MLME_DEBUG, sdata, link_id, \ + fmt, ##__VA_ARGS__) + +#define mlme_dbg_ratelimited(sdata, fmt, ...) \ + _sdata_dbg(MAC80211_MLME_DEBUG && net_ratelimit(), \ + sdata, fmt, ##__VA_ARGS__) + +#endif /* __MAC80211_DEBUG_H */ -- cgit v1.3.1