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 --- drivers/bluetooth/btbcm.h | 117 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 drivers/bluetooth/btbcm.h (limited to 'drivers/bluetooth/btbcm.h') diff --git a/drivers/bluetooth/btbcm.h b/drivers/bluetooth/btbcm.h new file mode 100644 index 000000000..b4cb24231 --- /dev/null +++ b/drivers/bluetooth/btbcm.h @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * + * Bluetooth support for Broadcom devices + * + * Copyright (C) 2015 Intel Corporation + */ + +#define BCM_UART_CLOCK_48MHZ 0x01 +#define BCM_UART_CLOCK_24MHZ 0x02 + +struct bcm_update_uart_baud_rate { + __le16 zero; + __le32 baud_rate; +} __packed; + +struct bcm_write_uart_clock_setting { + __u8 type; +} __packed; + +struct bcm_set_sleep_mode { + __u8 sleep_mode; + __u8 idle_host; + __u8 idle_dev; + __u8 bt_wake_active; + __u8 host_wake_active; + __u8 allow_host_sleep; + __u8 combine_modes; + __u8 tristate_control; + __u8 usb_auto_sleep; + __u8 usb_resume_timeout; + __u8 break_to_host; + __u8 pulsed_host_wake; +} __packed; + +struct bcm_set_pcm_int_params { + __u8 routing; + __u8 rate; + __u8 frame_sync; + __u8 sync_mode; + __u8 clock_mode; +} __packed; + +struct bcm_set_pcm_format_params { + __u8 lsb_first; + __u8 fill_value; + __u8 fill_method; + __u8 fill_num; + __u8 right_justify; +} __packed; + +#if IS_ENABLED(CONFIG_BT_BCM) + +int btbcm_check_bdaddr(struct hci_dev *hdev); +int btbcm_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr); +int btbcm_patchram(struct hci_dev *hdev, const struct firmware *fw); +int btbcm_read_pcm_int_params(struct hci_dev *hdev, + struct bcm_set_pcm_int_params *params); +int btbcm_write_pcm_int_params(struct hci_dev *hdev, + const struct bcm_set_pcm_int_params *params); + +int btbcm_setup_patchram(struct hci_dev *hdev); +int btbcm_setup_apple(struct hci_dev *hdev); + +int btbcm_initialize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode); +int btbcm_finalize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode); + +#else + +static inline int btbcm_check_bdaddr(struct hci_dev *hdev) +{ + return -EOPNOTSUPP; +} + +static inline int btbcm_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr) +{ + return -EOPNOTSUPP; +} + +static inline int btbcm_read_pcm_int_params(struct hci_dev *hdev, + struct bcm_set_pcm_int_params *params) +{ + return -EOPNOTSUPP; +} + +static inline int btbcm_write_pcm_int_params(struct hci_dev *hdev, + const struct bcm_set_pcm_int_params *params) +{ + return -EOPNOTSUPP; +} + +static inline int btbcm_patchram(struct hci_dev *hdev, const struct firmware *fw) +{ + return -EOPNOTSUPP; +} + +static inline int btbcm_setup_patchram(struct hci_dev *hdev) +{ + return 0; +} + +static inline int btbcm_setup_apple(struct hci_dev *hdev) +{ + return 0; +} + +static inline int btbcm_initialize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode) +{ + return 0; +} + +static inline int btbcm_finalize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode) +{ + return 0; +} + +#endif -- cgit v1.3.1