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 --- include/sound/sof/trace.h | 107 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) create mode 100644 include/sound/sof/trace.h (limited to 'include/sound/sof/trace.h') diff --git a/include/sound/sof/trace.h b/include/sound/sof/trace.h new file mode 100644 index 000000000..ac2ebb6fb --- /dev/null +++ b/include/sound/sof/trace.h @@ -0,0 +1,107 @@ +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */ +/* + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * Copyright(c) 2018 Intel Corporation + */ + +#ifndef __INCLUDE_SOUND_SOF_TRACE_H__ +#define __INCLUDE_SOUND_SOF_TRACE_H__ + +#include +#include + +/* + * DMA for Trace + */ + +#define SOF_TRACE_FILENAME_SIZE 32 + +/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS */ +/* Deprecated - use sof_ipc_dma_trace_params_ext */ +struct sof_ipc_dma_trace_params { + struct sof_ipc_cmd_hdr hdr; + struct sof_ipc_host_buffer buffer; + uint32_t stream_tag; +} __packed; + +/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS_EXT */ +struct sof_ipc_dma_trace_params_ext { + struct sof_ipc_cmd_hdr hdr; + struct sof_ipc_host_buffer buffer; + uint32_t stream_tag; + uint64_t timestamp_ns; /* in nanosecond */ + uint32_t reserved[8]; +} __packed; + +/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS */ +struct sof_ipc_dma_trace_posn { + struct sof_ipc_reply rhdr; + uint32_t host_offset; /* Offset of DMA host buffer */ + uint32_t overflow; /* overflow bytes if any */ + uint32_t messages; /* total trace messages */ +} __packed; + +/* Values used in sof_ipc_trace_filter_elem: */ + +/* bits 6..0 */ +#define SOF_IPC_TRACE_FILTER_ELEM_SET_LEVEL 0x01 /**< trace level for selected components */ +#define SOF_IPC_TRACE_FILTER_ELEM_BY_UUID 0x02 /**< filter by uuid key */ +#define SOF_IPC_TRACE_FILTER_ELEM_BY_PIPE 0x03 /**< filter by pipeline */ +#define SOF_IPC_TRACE_FILTER_ELEM_BY_COMP 0x04 /**< filter by component id */ + +/* bit 7 */ +#define SOF_IPC_TRACE_FILTER_ELEM_FIN 0x80 /**< mark last filter in set */ + +/* bits 31..8: Unused */ + +/** part of sof_ipc_trace_filter, ABI3.17 */ +struct sof_ipc_trace_filter_elem { + uint32_t key; /**< SOF_IPC_TRACE_FILTER_ELEM_ {LEVEL, UUID, COMP, PIPE} */ + uint32_t value; /**< element value */ +} __packed; + +/** Runtime tracing filtration data - SOF_IPC_TRACE_FILTER_UPDATE, ABI3.17 */ +struct sof_ipc_trace_filter { + struct sof_ipc_cmd_hdr hdr; /**< IPC command header */ + uint32_t elem_cnt; /**< number of entries in elems[] array */ + uint32_t reserved[8]; /**< reserved for future usage */ + /** variable size array with new filtering settings */ + struct sof_ipc_trace_filter_elem elems[]; +} __packed; + +/* + * Commom debug + */ + +/* + * SOF panic codes + */ +#define SOF_IPC_PANIC_MAGIC 0x0dead000 +#define SOF_IPC_PANIC_MAGIC_MASK 0x0ffff000 +#define SOF_IPC_PANIC_CODE_MASK 0x00000fff +#define SOF_IPC_PANIC_MEM (SOF_IPC_PANIC_MAGIC | 0x0) +#define SOF_IPC_PANIC_WORK (SOF_IPC_PANIC_MAGIC | 0x1) +#define SOF_IPC_PANIC_IPC (SOF_IPC_PANIC_MAGIC | 0x2) +#define SOF_IPC_PANIC_ARCH (SOF_IPC_PANIC_MAGIC | 0x3) +#define SOF_IPC_PANIC_PLATFORM (SOF_IPC_PANIC_MAGIC | 0x4) +#define SOF_IPC_PANIC_TASK (SOF_IPC_PANIC_MAGIC | 0x5) +#define SOF_IPC_PANIC_EXCEPTION (SOF_IPC_PANIC_MAGIC | 0x6) +#define SOF_IPC_PANIC_DEADLOCK (SOF_IPC_PANIC_MAGIC | 0x7) +#define SOF_IPC_PANIC_STACK (SOF_IPC_PANIC_MAGIC | 0x8) +#define SOF_IPC_PANIC_IDLE (SOF_IPC_PANIC_MAGIC | 0x9) +#define SOF_IPC_PANIC_WFI (SOF_IPC_PANIC_MAGIC | 0xa) +#define SOF_IPC_PANIC_ASSERT (SOF_IPC_PANIC_MAGIC | 0xb) + +/* panic info include filename and line number + * filename array will not include null terminator if fully filled + */ +struct sof_ipc_panic_info { + struct sof_ipc_hdr hdr; + uint32_t code; /* SOF_IPC_PANIC_ */ + uint8_t filename[SOF_TRACE_FILENAME_SIZE]; + uint32_t linenum; +} __packed; + +#endif -- cgit v1.3.1