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/clk/imx/Makefile | 60 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 drivers/clk/imx/Makefile (limited to 'drivers/clk/imx/Makefile') diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile new file mode 100644 index 000000000..208b46873 --- /dev/null +++ b/drivers/clk/imx/Makefile @@ -0,0 +1,60 @@ +# SPDX-License-Identifier: GPL-2.0 + +mxc-clk-objs += clk.o +mxc-clk-objs += clk-busy.o +mxc-clk-objs += clk-composite-7ulp.o +mxc-clk-objs += clk-composite-8m.o +mxc-clk-objs += clk-composite-93.o +mxc-clk-objs += clk-fracn-gppll.o +mxc-clk-objs += clk-cpu.o +mxc-clk-objs += clk-divider-gate.o +mxc-clk-objs += clk-fixup-div.o +mxc-clk-objs += clk-fixup-mux.o +mxc-clk-objs += clk-frac-pll.o +mxc-clk-objs += clk-gate2.o +mxc-clk-objs += clk-gate-93.o +mxc-clk-objs += clk-gate-exclusive.o +mxc-clk-objs += clk-pfd.o +mxc-clk-objs += clk-pfdv2.o +mxc-clk-objs += clk-pllv1.o +mxc-clk-objs += clk-pllv2.o +mxc-clk-objs += clk-pllv3.o +mxc-clk-objs += clk-pllv4.o +mxc-clk-objs += clk-pll14xx.o +mxc-clk-objs += clk-sscg-pll.o +mxc-clk-objs += clk-gpr-mux.o +obj-$(CONFIG_MXC_CLK) += mxc-clk.o + +obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o +obj-$(CONFIG_CLK_IMX8MN) += clk-imx8mn.o +obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o clk-imx8mp-audiomix.o +obj-$(CONFIG_CLK_IMX8MQ) += clk-imx8mq.o + +obj-$(CONFIG_CLK_IMX93) += clk-imx93.o +obj-$(CONFIG_CLK_IMX95_BLK_CTL) += clk-imx95-blk-ctl.o + +obj-$(CONFIG_MXC_CLK_SCU) += clk-imx-scu.o clk-imx-lpcg-scu.o clk-imx-acm.o +clk-imx-scu-$(CONFIG_CLK_IMX8QXP) += clk-scu.o clk-imx8qxp.o \ + clk-imx8qxp-rsrc.o clk-imx8qm-rsrc.o \ + clk-imx8dxl-rsrc.o +clk-imx-lpcg-scu-$(CONFIG_CLK_IMX8QXP) += clk-lpcg-scu.o clk-imx8qxp-lpcg.o +clk-imx-acm-$(CONFIG_CLK_IMX8QXP) = clk-imx8-acm.o + +obj-$(CONFIG_CLK_IMX8ULP) += clk-imx8ulp.o +obj-$(CONFIG_CLK_IMX8ULP) += clk-imx8ulp-sim-lpav.o + +obj-$(CONFIG_CLK_IMX1) += clk-imx1.o +obj-$(CONFIG_CLK_IMX25) += clk-imx25.o +obj-$(CONFIG_CLK_IMX27) += clk-imx27.o +obj-$(CONFIG_CLK_IMX31) += clk-imx31.o +obj-$(CONFIG_CLK_IMX35) += clk-imx35.o +obj-$(CONFIG_CLK_IMX5) += clk-imx5.o +obj-$(CONFIG_CLK_IMX6Q) += clk-imx6q.o +obj-$(CONFIG_CLK_IMX6SL) += clk-imx6sl.o +obj-$(CONFIG_CLK_IMX6SLL) += clk-imx6sll.o +obj-$(CONFIG_CLK_IMX6SX) += clk-imx6sx.o +obj-$(CONFIG_CLK_IMX6UL) += clk-imx6ul.o +obj-$(CONFIG_CLK_IMX7D) += clk-imx7d.o +obj-$(CONFIG_CLK_IMX7ULP) += clk-imx7ulp.o +obj-$(CONFIG_CLK_IMXRT1050) += clk-imxrt1050.o +obj-$(CONFIG_CLK_VF610) += clk-vf610.o -- cgit v1.3.1