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 --- sound/soc/sof/sof-client.h | 79 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 sound/soc/sof/sof-client.h (limited to 'sound/soc/sof/sof-client.h') diff --git a/sound/soc/sof/sof-client.h b/sound/soc/sof/sof-client.h new file mode 100644 index 000000000..3b02506c0 --- /dev/null +++ b/sound/soc/sof/sof-client.h @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __SOC_SOF_CLIENT_H +#define __SOC_SOF_CLIENT_H + +#include +#include +#include +#include + +struct sof_ipc_fw_version; +struct sof_ipc_cmd_hdr; +struct snd_sof_dev; +struct dentry; + +struct sof_ipc4_fw_module; + +/** + * struct sof_client_dev - SOF client device + * @auxdev: auxiliary device + * @data: device specific data + */ +struct sof_client_dev { + struct auxiliary_device auxdev; + void *data; +}; + +#define auxiliary_dev_to_sof_client_dev(auxiliary_dev) \ + container_of(auxiliary_dev, struct sof_client_dev, auxdev) + +#define dev_to_sof_client_dev(dev) \ + container_of(to_auxiliary_dev(dev), struct sof_client_dev, auxdev) + +int sof_client_ipc_tx_message(struct sof_client_dev *cdev, void *ipc_msg, + void *reply_data, size_t reply_bytes); +static inline int sof_client_ipc_tx_message_no_reply(struct sof_client_dev *cdev, void *ipc_msg) +{ + return sof_client_ipc_tx_message(cdev, ipc_msg, NULL, 0); +} +int sof_client_ipc_set_get_data(struct sof_client_dev *cdev, void *ipc_msg, + bool set); + +struct sof_ipc4_fw_module *sof_client_ipc4_find_module(struct sof_client_dev *c, const guid_t *u); +struct snd_sof_widget *sof_client_ipc4_find_swidget_by_id(struct sof_client_dev *cdev, + u32 module_id, int instance_id); + +struct dentry *sof_client_get_debugfs_root(struct sof_client_dev *cdev); +struct device *sof_client_get_dma_dev(struct sof_client_dev *cdev); +const struct sof_ipc_fw_version *sof_client_get_fw_version(struct sof_client_dev *cdev); +size_t sof_client_get_ipc_max_payload_size(struct sof_client_dev *cdev); +enum sof_ipc_type sof_client_get_ipc_type(struct sof_client_dev *cdev); + +/* DSP/firmware boot request */ +int sof_client_boot_dsp(struct sof_client_dev *cdev); + +/* module refcount management of SOF core */ +int sof_client_core_module_get(struct sof_client_dev *cdev); +void sof_client_core_module_put(struct sof_client_dev *cdev); + +/* IPC notification */ +typedef void (*sof_client_event_callback)(struct sof_client_dev *cdev, void *msg_buf); + +int sof_client_register_ipc_rx_handler(struct sof_client_dev *cdev, + u32 ipc_msg_type, + sof_client_event_callback callback); +void sof_client_unregister_ipc_rx_handler(struct sof_client_dev *cdev, + u32 ipc_msg_type); + +/* DSP state notification and query */ +typedef void (*sof_client_fw_state_callback)(struct sof_client_dev *cdev, + enum sof_fw_state state); + +int sof_client_register_fw_state_handler(struct sof_client_dev *cdev, + sof_client_fw_state_callback callback); +void sof_client_unregister_fw_state_handler(struct sof_client_dev *cdev); +enum sof_fw_state sof_client_get_fw_state(struct sof_client_dev *cdev); +int sof_client_ipc_rx_message(struct sof_client_dev *cdev, void *ipc_msg, void *msg_buf); + +#endif /* __SOC_SOF_CLIENT_H */ -- cgit v1.3.1