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/input/mouse/elantech.h | 205 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 205 insertions(+) create mode 100644 drivers/input/mouse/elantech.h (limited to 'drivers/input/mouse/elantech.h') diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h new file mode 100644 index 000000000..571e6ca11 --- /dev/null +++ b/drivers/input/mouse/elantech.h @@ -0,0 +1,205 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Elantech Touchpad driver (v6) + * + * Copyright (C) 2007-2009 Arjan Opmeer + * + * Trademarks are the property of their respective owners. + */ + +#ifndef _ELANTECH_H +#define _ELANTECH_H + +/* + * Command values for Synaptics style queries + */ +#define ETP_FW_ID_QUERY 0x00 +#define ETP_FW_VERSION_QUERY 0x01 +#define ETP_CAPABILITIES_QUERY 0x02 +#define ETP_SAMPLE_QUERY 0x03 +#define ETP_RESOLUTION_QUERY 0x04 +#define ETP_ICBODY_QUERY 0x05 + +/* + * Command values for register reading or writing + */ +#define ETP_REGISTER_READ 0x10 +#define ETP_REGISTER_WRITE 0x11 +#define ETP_REGISTER_READWRITE 0x00 + +/* + * Hardware version 2 custom PS/2 command value + */ +#define ETP_PS2_CUSTOM_COMMAND 0xf8 + +/* + * Times to retry a ps2_command and millisecond delay between tries + */ +#define ETP_PS2_COMMAND_TRIES 3 +#define ETP_PS2_COMMAND_DELAY 500 + +/* + * Times to try to read back a register and millisecond delay between tries + */ +#define ETP_READ_BACK_TRIES 5 +#define ETP_READ_BACK_DELAY 2000 + +/* + * Register bitmasks for hardware version 1 + */ +#define ETP_R10_ABSOLUTE_MODE 0x04 +#define ETP_R11_4_BYTE_MODE 0x02 + +/* + * Capability bitmasks + */ +#define ETP_CAP_HAS_ROCKER 0x04 + +/* + * One hard to find application note states that X axis range is 0 to 576 + * and Y axis range is 0 to 384 for harware version 1. + * Edge fuzz might be necessary because of bezel around the touchpad + */ +#define ETP_EDGE_FUZZ_V1 32 + +#define ETP_XMIN_V1 ( 0 + ETP_EDGE_FUZZ_V1) +#define ETP_XMAX_V1 (576 - ETP_EDGE_FUZZ_V1) +#define ETP_YMIN_V1 ( 0 + ETP_EDGE_FUZZ_V1) +#define ETP_YMAX_V1 (384 - ETP_EDGE_FUZZ_V1) + +/* + * The resolution for older v2 hardware doubled. + * (newer v2's firmware provides command so we can query) + */ +#define ETP_XMIN_V2 0 +#define ETP_XMAX_V2 1152 +#define ETP_YMIN_V2 0 +#define ETP_YMAX_V2 768 + +#define ETP_PMIN_V2 0 +#define ETP_PMAX_V2 255 +#define ETP_WMIN_V2 0 +#define ETP_WMAX_V2 15 + +/* + * v3 hardware has 2 kinds of packet types, + * v4 hardware has 3. + */ +#define PACKET_UNKNOWN 0x01 +#define PACKET_DEBOUNCE 0x02 +#define PACKET_V3_HEAD 0x03 +#define PACKET_V3_TAIL 0x04 +#define PACKET_V4_HEAD 0x05 +#define PACKET_V4_MOTION 0x06 +#define PACKET_V4_STATUS 0x07 +#define PACKET_TRACKPOINT 0x08 + +/* + * track up to 5 fingers for v4 hardware + */ +#define ETP_MAX_FINGERS 5 + +/* + * weight value for v4 hardware + */ +#define ETP_WEIGHT_VALUE 5 + +/* + * Bus information on 3rd byte of query ETP_RESOLUTION_QUERY(0x04) + */ +#define ETP_BUS_PS2_ONLY 0 +#define ETP_BUS_SMB_ALERT_ONLY 1 +#define ETP_BUS_SMB_HST_NTFY_ONLY 2 +#define ETP_BUS_PS2_SMB_ALERT 3 +#define ETP_BUS_PS2_SMB_HST_NTFY 4 + +/* + * New ICs are either using SMBus Host Notify or just plain PS2. + * + * ETP_FW_VERSION_QUERY is: + * Byte 1: + * - bit 0..3: IC BODY + * Byte 2: + * - bit 4: HiddenButton + * - bit 5: PS2_SMBUS_NOTIFY + * - bit 6: PS2CRCCheck + */ +#define ETP_NEW_IC_SMBUS_HOST_NOTIFY(fw_version) \ + ((((fw_version) & 0x0f2000) == 0x0f2000) && \ + ((fw_version) & 0x0000ff) > 0) + +/* + * The base position for one finger, v4 hardware + */ +struct finger_pos { + unsigned int x; + unsigned int y; +}; + +struct elantech_device_info { + unsigned char capabilities[3]; + unsigned char samples[3]; + unsigned char debug; + unsigned char hw_version; + unsigned char pattern; + unsigned int fw_version; + unsigned int ic_version; + unsigned int product_id; + unsigned int x_min; + unsigned int y_min; + unsigned int x_max; + unsigned int y_max; + unsigned int x_res; + unsigned int y_res; + unsigned int x_traces; + unsigned int y_traces; + unsigned int width; + unsigned int bus; + bool paritycheck; + bool jumpy_cursor; + bool reports_pressure; + bool crc_enabled; + bool set_hw_resolution; + bool has_trackpoint; + bool has_middle_button; + int (*send_cmd)(struct psmouse *psmouse, unsigned char c, + unsigned char *param); +}; + +struct elantech_data { + struct input_dev *tp_dev; /* Relative device for trackpoint */ + char tp_phys[32]; + unsigned char reg_07; + unsigned char reg_10; + unsigned char reg_11; + unsigned char reg_20; + unsigned char reg_21; + unsigned char reg_22; + unsigned char reg_23; + unsigned char reg_24; + unsigned char reg_25; + unsigned char reg_26; + unsigned int single_finger_reports; + unsigned int y_max; + unsigned int width; + struct finger_pos mt[ETP_MAX_FINGERS]; + unsigned char parity[256]; + struct elantech_device_info info; + void (*original_set_rate)(struct psmouse *psmouse, unsigned int rate); +}; + +int elantech_detect(struct psmouse *psmouse, bool set_properties); +int elantech_init_ps2(struct psmouse *psmouse); + +#ifdef CONFIG_MOUSE_PS2_ELANTECH +int elantech_init(struct psmouse *psmouse); +#else +static inline int elantech_init(struct psmouse *psmouse) +{ + return -ENOSYS; +} +#endif /* CONFIG_MOUSE_PS2_ELANTECH */ + +int elantech_init_smbus(struct psmouse *psmouse); + +#endif -- cgit v1.3.1