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/fpga/Makefile | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 drivers/fpga/Makefile (limited to 'drivers/fpga/Makefile') diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile new file mode 100644 index 000000000..6f5798b27 --- /dev/null +++ b/drivers/fpga/Makefile @@ -0,0 +1,63 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the fpga framework and fpga manager drivers. +# + +# Core FPGA Manager Framework +obj-$(CONFIG_FPGA) += fpga-mgr.o + +# FPGA Manager Drivers +obj-$(CONFIG_FPGA_MGR_ALTERA_CVP) += altera-cvp.o +obj-$(CONFIG_FPGA_MGR_ALTERA_PS_SPI) += altera-ps-spi.o +obj-$(CONFIG_FPGA_MGR_ICE40_SPI) += ice40-spi.o +obj-$(CONFIG_FPGA_MGR_MACHXO2_SPI) += machxo2-spi.o +obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o +obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o +obj-$(CONFIG_FPGA_MGR_STRATIX10_SOC) += stratix10-soc.o +obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o +obj-$(CONFIG_FPGA_MGR_XILINX_CORE) += xilinx-core.o +obj-$(CONFIG_FPGA_MGR_XILINX_SELECTMAP) += xilinx-selectmap.o +obj-$(CONFIG_FPGA_MGR_XILINX_SPI) += xilinx-spi.o +obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o +obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA) += zynqmp-fpga.o +obj-$(CONFIG_FPGA_MGR_VERSAL_FPGA) += versal-fpga.o +obj-$(CONFIG_FPGA_MGR_MICROCHIP_SPI) += microchip-spi.o +obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG) += lattice-sysconfig.o +obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG_SPI) += lattice-sysconfig-spi.o +obj-$(CONFIG_ALTERA_PR_IP_CORE) += altera-pr-ip-core.o +obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT) += altera-pr-ip-core-plat.o +obj-$(CONFIG_FPGA_MGR_EFINIX_SPI) += efinix-spi.o + +# FPGA Secure Update Drivers +obj-$(CONFIG_FPGA_M10_BMC_SEC_UPDATE) += intel-m10-bmc-sec-update.o + +# FPGA Bridge Drivers +obj-$(CONFIG_FPGA_BRIDGE) += fpga-bridge.o +obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE) += altera-hps2fpga.o altera-fpga2sdram.o +obj-$(CONFIG_ALTERA_FREEZE_BRIDGE) += altera-freeze-bridge.o +obj-$(CONFIG_XILINX_PR_DECOUPLER) += xilinx-pr-decoupler.o + +# High Level Interfaces +obj-$(CONFIG_FPGA_REGION) += fpga-region.o +obj-$(CONFIG_OF_FPGA_REGION) += of-fpga-region.o + +# FPGA Device Feature List Support +obj-$(CONFIG_FPGA_DFL) += dfl.o +obj-$(CONFIG_FPGA_DFL_FME) += dfl-fme.o +obj-$(CONFIG_FPGA_DFL_FME_MGR) += dfl-fme-mgr.o +obj-$(CONFIG_FPGA_DFL_FME_BRIDGE) += dfl-fme-br.o +obj-$(CONFIG_FPGA_DFL_FME_REGION) += dfl-fme-region.o +obj-$(CONFIG_FPGA_DFL_AFU) += dfl-afu.o + +dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o dfl-fme-error.o +dfl-fme-objs += dfl-fme-perf.o +dfl-afu-objs := dfl-afu-main.o dfl-afu-region.o dfl-afu-dma-region.o +dfl-afu-objs += dfl-afu-error.o + +obj-$(CONFIG_FPGA_DFL_NIOS_INTEL_PAC_N3000) += dfl-n3000-nios.o + +# Drivers for FPGAs which implement DFL +obj-$(CONFIG_FPGA_DFL_PCI) += dfl-pci.o + +# KUnit tests +obj-$(CONFIG_FPGA_KUNIT_TESTS) += tests/ -- cgit v1.3.1