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/net/phy/rockchip.c | 200 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 200 insertions(+) create mode 100644 drivers/net/phy/rockchip.c (limited to 'drivers/net/phy/rockchip.c') diff --git a/drivers/net/phy/rockchip.c b/drivers/net/phy/rockchip.c new file mode 100644 index 000000000..b338f385e --- /dev/null +++ b/drivers/net/phy/rockchip.c @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * drivers/net/phy/rockchip.c + * + * Driver for ROCKCHIP Ethernet PHYs + * + * Copyright (c) 2017, Fuzhou Rockchip Electronics Co., Ltd + * + * David Wu + */ + +#include +#include +#include +#include +#include +#include + +#define INTERNAL_EPHY_ID 0x1234d400 + +#define MII_INTERNAL_CTRL_STATUS 17 +#define SMI_ADDR_TSTCNTL 20 +#define SMI_ADDR_TSTREAD1 21 +#define SMI_ADDR_TSTREAD2 22 +#define SMI_ADDR_TSTWRITE 23 +#define MII_SPECIAL_CONTROL_STATUS 31 + +#define MII_AUTO_MDIX_EN BIT(7) +#define MII_MDIX_EN BIT(6) + +#define MII_SPEED_10 BIT(2) +#define MII_SPEED_100 BIT(3) + +#define TSTCNTL_RD (BIT(15) | BIT(10)) +#define TSTCNTL_WR (BIT(14) | BIT(10)) + +#define TSTMODE_ENABLE 0x400 +#define TSTMODE_DISABLE 0x0 + +#define WR_ADDR_A7CFG 0x18 + +static int rockchip_init_tstmode(struct phy_device *phydev) +{ + int ret; + + /* Enable access to Analog and DSP register banks */ + ret = phy_write(phydev, SMI_ADDR_TSTCNTL, TSTMODE_ENABLE); + if (ret) + return ret; + + ret = phy_write(phydev, SMI_ADDR_TSTCNTL, TSTMODE_DISABLE); + if (ret) + return ret; + + return phy_write(phydev, SMI_ADDR_TSTCNTL, TSTMODE_ENABLE); +} + +static int rockchip_close_tstmode(struct phy_device *phydev) +{ + /* Back to basic register bank */ + return phy_write(phydev, SMI_ADDR_TSTCNTL, TSTMODE_DISABLE); +} + +static int rockchip_integrated_phy_analog_init(struct phy_device *phydev) +{ + int ret; + + ret = rockchip_init_tstmode(phydev); + if (ret) + return ret; + + /* + * Adjust tx amplitude to make sginal better, + * the default value is 0x8. + */ + ret = phy_write(phydev, SMI_ADDR_TSTWRITE, 0xB); + if (ret) + return ret; + ret = phy_write(phydev, SMI_ADDR_TSTCNTL, TSTCNTL_WR | WR_ADDR_A7CFG); + if (ret) + return ret; + + return rockchip_close_tstmode(phydev); +} + +static int rockchip_integrated_phy_config_init(struct phy_device *phydev) +{ + int val, ret; + + /* + * The auto MIDX has linked problem on some board, + * workround to disable auto MDIX. + */ + val = phy_read(phydev, MII_INTERNAL_CTRL_STATUS); + if (val < 0) + return val; + val &= ~MII_AUTO_MDIX_EN; + ret = phy_write(phydev, MII_INTERNAL_CTRL_STATUS, val); + if (ret) + return ret; + + return rockchip_integrated_phy_analog_init(phydev); +} + +static void rockchip_link_change_notify(struct phy_device *phydev) +{ + /* + * If mode switch happens from 10BT to 100BT, all DSP/AFE + * registers are set to default values. So any AFE/DSP + * registers have to be re-initialized in this case. + */ + if (phydev->state == PHY_RUNNING && phydev->speed == SPEED_100) { + int ret = rockchip_integrated_phy_analog_init(phydev); + + if (ret) + phydev_err(phydev, "rockchip_integrated_phy_analog_init err: %d.\n", + ret); + } +} + +static int rockchip_set_polarity(struct phy_device *phydev, int polarity) +{ + int reg, err, val; + + /* get the current settings */ + reg = phy_read(phydev, MII_INTERNAL_CTRL_STATUS); + if (reg < 0) + return reg; + + reg &= ~MII_AUTO_MDIX_EN; + val = reg; + switch (polarity) { + case ETH_TP_MDI: + val &= ~MII_MDIX_EN; + break; + case ETH_TP_MDI_X: + val |= MII_MDIX_EN; + break; + case ETH_TP_MDI_AUTO: + case ETH_TP_MDI_INVALID: + default: + return 0; + } + + if (val != reg) { + /* Set the new polarity value in the register */ + err = phy_write(phydev, MII_INTERNAL_CTRL_STATUS, val); + if (err) + return err; + } + + return 0; +} + +static int rockchip_config_aneg(struct phy_device *phydev) +{ + int err; + + err = rockchip_set_polarity(phydev, phydev->mdix); + if (err < 0) + return err; + + return genphy_config_aneg(phydev); +} + +static int rockchip_phy_resume(struct phy_device *phydev) +{ + genphy_resume(phydev); + + return rockchip_integrated_phy_config_init(phydev); +} + +static struct phy_driver rockchip_phy_driver[] = { +{ + .phy_id = INTERNAL_EPHY_ID, + .phy_id_mask = 0xfffffff0, + .name = "Rockchip integrated EPHY", + /* PHY_BASIC_FEATURES */ + .flags = 0, + .link_change_notify = rockchip_link_change_notify, + .soft_reset = genphy_soft_reset, + .config_init = rockchip_integrated_phy_config_init, + .config_aneg = rockchip_config_aneg, + .suspend = genphy_suspend, + .resume = rockchip_phy_resume, +}, +}; + +module_phy_driver(rockchip_phy_driver); + +static const struct mdio_device_id __maybe_unused rockchip_phy_tbl[] = { + { INTERNAL_EPHY_ID, 0xfffffff0 }, + { } +}; + +MODULE_DEVICE_TABLE(mdio, rockchip_phy_tbl); + +MODULE_AUTHOR("David Wu "); +MODULE_DESCRIPTION("Rockchip Ethernet PHY driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1