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/mfd/ac100.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 drivers/mfd/ac100.c (limited to 'drivers/mfd/ac100.c') diff --git a/drivers/mfd/ac100.c b/drivers/mfd/ac100.c new file mode 100644 index 000000000..8f47c392c --- /dev/null +++ b/drivers/mfd/ac100.c @@ -0,0 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MFD core driver for X-Powers' AC100 Audio Codec IC + * + * The AC100 is a highly integrated audio codec and RTC subsystem designed + * for mobile applications. It has 3 I2S/PCM interfaces, a 2 channel DAC, + * a 2 channel ADC with 5 inputs and a builtin mixer. The RTC subsystem has + * 3 clock outputs. + * + * The audio codec and RTC parts are completely separate, sharing only the + * host interface for access to its registers. + * + * Copyright (2016) Chen-Yu Tsai + * + * Author: Chen-Yu Tsai + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +static const struct regmap_range ac100_writeable_ranges[] = { + regmap_reg_range(AC100_CHIP_AUDIO_RST, AC100_I2S_SR_CTRL), + regmap_reg_range(AC100_I2S1_CLK_CTRL, AC100_I2S1_MXR_GAIN), + regmap_reg_range(AC100_I2S2_CLK_CTRL, AC100_I2S2_MXR_GAIN), + regmap_reg_range(AC100_I2S3_CLK_CTRL, AC100_I2S3_SIG_PATH_CTRL), + regmap_reg_range(AC100_ADC_DIG_CTRL, AC100_ADC_VOL_CTRL), + regmap_reg_range(AC100_HMIC_CTRL1, AC100_HMIC_STATUS), + regmap_reg_range(AC100_DAC_DIG_CTRL, AC100_DAC_MXR_GAIN), + regmap_reg_range(AC100_ADC_APC_CTRL, AC100_LINEOUT_CTRL), + regmap_reg_range(AC100_ADC_DAP_L_CTRL, AC100_ADC_DAP_OPT), + regmap_reg_range(AC100_DAC_DAP_CTRL, AC100_DAC_DAP_OPT), + regmap_reg_range(AC100_ADC_DAP_ENA, AC100_DAC_DAP_ENA), + regmap_reg_range(AC100_SRC1_CTRL1, AC100_SRC1_CTRL2), + regmap_reg_range(AC100_SRC2_CTRL1, AC100_SRC2_CTRL2), + regmap_reg_range(AC100_CLK32K_ANALOG_CTRL, AC100_CLKOUT_CTRL3), + regmap_reg_range(AC100_RTC_RST, AC100_RTC_UPD), + regmap_reg_range(AC100_ALM_INT_ENA, AC100_ALM_INT_STA), + regmap_reg_range(AC100_ALM_SEC, AC100_RTC_GP(15)), +}; + +static const struct regmap_range ac100_volatile_ranges[] = { + regmap_reg_range(AC100_CHIP_AUDIO_RST, AC100_PLL_CTRL2), + regmap_reg_range(AC100_HMIC_STATUS, AC100_HMIC_STATUS), + regmap_reg_range(AC100_ADC_DAP_L_STA, AC100_ADC_DAP_L_STA), + regmap_reg_range(AC100_SRC1_CTRL1, AC100_SRC1_CTRL1), + regmap_reg_range(AC100_SRC1_CTRL3, AC100_SRC2_CTRL1), + regmap_reg_range(AC100_SRC2_CTRL3, AC100_SRC2_CTRL4), + regmap_reg_range(AC100_RTC_RST, AC100_RTC_RST), + regmap_reg_range(AC100_RTC_SEC, AC100_ALM_INT_STA), + regmap_reg_range(AC100_ALM_SEC, AC100_ALM_UPD), +}; + +static const struct regmap_access_table ac100_writeable_table = { + .yes_ranges = ac100_writeable_ranges, + .n_yes_ranges = ARRAY_SIZE(ac100_writeable_ranges), +}; + +static const struct regmap_access_table ac100_volatile_table = { + .yes_ranges = ac100_volatile_ranges, + .n_yes_ranges = ARRAY_SIZE(ac100_volatile_ranges), +}; + +static const struct regmap_config ac100_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .wr_table = &ac100_writeable_table, + .volatile_table = &ac100_volatile_table, + .max_register = AC100_RTC_GP(15), + .cache_type = REGCACHE_MAPLE, +}; + +static struct mfd_cell ac100_cells[] = { + { + .name = "ac100-codec", + .of_compatible = "x-powers,ac100-codec", + }, { + .name = "ac100-rtc", + .of_compatible = "x-powers,ac100-rtc", + }, +}; + +static int ac100_rsb_probe(struct sunxi_rsb_device *rdev) +{ + struct ac100_dev *ac100; + int ret; + + ac100 = devm_kzalloc(&rdev->dev, sizeof(*ac100), GFP_KERNEL); + if (!ac100) + return -ENOMEM; + + ac100->dev = &rdev->dev; + sunxi_rsb_device_set_drvdata(rdev, ac100); + + ac100->regmap = devm_regmap_init_sunxi_rsb(rdev, &ac100_regmap_config); + if (IS_ERR(ac100->regmap)) { + ret = PTR_ERR(ac100->regmap); + dev_err(ac100->dev, "regmap init failed: %d\n", ret); + return ret; + } + + ret = devm_mfd_add_devices(ac100->dev, PLATFORM_DEVID_NONE, ac100_cells, + ARRAY_SIZE(ac100_cells), NULL, 0, NULL); + if (ret) { + dev_err(ac100->dev, "failed to add MFD devices: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct of_device_id ac100_of_match[] = { + { .compatible = "x-powers,ac100" }, + { }, +}; +MODULE_DEVICE_TABLE(of, ac100_of_match); + +static struct sunxi_rsb_driver ac100_rsb_driver = { + .driver = { + .name = "ac100", + .of_match_table = of_match_ptr(ac100_of_match), + }, + .probe = ac100_rsb_probe, +}; +module_sunxi_rsb_driver(ac100_rsb_driver); + +MODULE_DESCRIPTION("Audio codec MFD core driver for AC100"); +MODULE_AUTHOR("Chen-Yu Tsai "); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1