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 --- arch/mips/boot/Makefile | 176 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 176 insertions(+) create mode 100644 arch/mips/boot/Makefile (limited to 'arch/mips/boot/Makefile') diff --git a/arch/mips/boot/Makefile b/arch/mips/boot/Makefile new file mode 100644 index 000000000..8473c4671 --- /dev/null +++ b/arch/mips/boot/Makefile @@ -0,0 +1,176 @@ +# +# This file is subject to the terms and conditions of the GNU General Public +# License. See the file "COPYING" in the main directory of this archive +# for more details. +# +# Copyright (C) 1995, 1998, 2001, 2002 by Ralf Baechle +# Copyright (C) 2004 Maciej W. Rozycki +# + +# +# Some DECstations need all possible sections of an ECOFF executable +# +ifdef CONFIG_MACH_DECSTATION + e2eflag := -a +endif + +# +# Drop some uninteresting sections in the kernel. +# This is only relevant for ELF kernels but doesn't hurt a.out +# +drop-sections := .reginfo .mdebug .comment .note .pdr .options .MIPS.options +strip-flags := $(addprefix --remove-section=,$(drop-sections)) + +hostprogs := elf2ecoff + +suffix-y := bin +suffix-$(CONFIG_KERNEL_BZIP2) := bz2 +suffix-$(CONFIG_KERNEL_GZIP) := gz +suffix-$(CONFIG_KERNEL_LZMA) := lzma +suffix-$(CONFIG_KERNEL_LZO) := lzo + +targets := vmlinux.ecoff +quiet_cmd_ecoff = ECOFF $@ + cmd_ecoff = $(obj)/elf2ecoff $(VMLINUX) $@ $(e2eflag) +$(obj)/vmlinux.ecoff: $(obj)/elf2ecoff $(VMLINUX) FORCE + $(call if_changed,ecoff) + +targets += vmlinux.bin +quiet_cmd_bin = OBJCOPY $@ + cmd_bin = $(OBJCOPY) -O binary $(strip-flags) $(VMLINUX) $@ +$(obj)/vmlinux.bin: $(VMLINUX) FORCE + $(call if_changed,bin) + +targets += vmlinux.srec +quiet_cmd_srec = OBJCOPY $@ + cmd_srec = $(OBJCOPY) -S -O srec $(strip-flags) $(VMLINUX) $@ +$(obj)/vmlinux.srec: $(VMLINUX) FORCE + $(call if_changed,srec) + +UIMAGE_LOADADDR = $(VMLINUX_LOAD_ADDRESS) +UIMAGE_ENTRYADDR = $(VMLINUX_ENTRY_ADDRESS) + +# +# Compressed vmlinux images +# + +targets += vmlinux.bin.bz2 +targets += vmlinux.bin.gz +targets += vmlinux.bin.lzma +targets += vmlinux.bin.lzo + +$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE + $(call if_changed,bzip2) + +$(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE + $(call if_changed,gzip) + +$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE + $(call if_changed,lzma) + +$(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE + $(call if_changed,lzo) + +# +# Compressed u-boot images +# + +targets += uImage +targets += uImage.bin +targets += uImage.bz2 +targets += uImage.gz +targets += uImage.lzma +targets += uImage.lzo + +$(obj)/uImage.bin: $(obj)/vmlinux.bin FORCE + $(call if_changed,uimage,none) + +$(obj)/uImage.bz2: $(obj)/vmlinux.bin.bz2 FORCE + $(call if_changed,uimage,bzip2) + +$(obj)/uImage.gz: $(obj)/vmlinux.bin.gz FORCE + $(call if_changed,uimage,gzip) + +$(obj)/uImage.lzma: $(obj)/vmlinux.bin.lzma FORCE + $(call if_changed,uimage,lzma) + +$(obj)/uImage.lzo: $(obj)/vmlinux.bin.lzo FORCE + $(call if_changed,uimage,lzo) + +$(obj)/uImage: $(obj)/uImage.$(suffix-y) + @ln -sf $(notdir $<) $@ + @echo ' Image $@ is ready' + +# +# Flattened Image Tree (.itb) images +# + +ifeq ($(ADDR_BITS),32) +itb_addr_cells = 1 +endif +ifeq ($(ADDR_BITS),64) +itb_addr_cells = 2 +endif + +targets += vmlinux.its.S + +quiet_cmd_its_cat = CAT $@ + cmd_its_cat = cat $(real-prereqs) >$@ + +$(obj)/vmlinux.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS)) FORCE + $(call if_changed,its_cat) + +targets += vmlinux.its +targets += vmlinux.gz.its +targets += vmlinux.bz2.its +targets += vmlinux.lzma.its +targets += vmlinux.lzo.its + +quiet_cmd_cpp_its_S = ITS $@ + cmd_cpp_its_S = $(CPP) -P -C -o $@ $< \ + -DKERNEL_NAME="\"Linux $(KERNELRELEASE)\"" \ + -DVMLINUX_BINARY="\"$(3)\"" \ + -DVMLINUX_COMPRESSION="\"$(2)\"" \ + -DVMLINUX_LOAD_ADDRESS=$(VMLINUX_LOAD_ADDRESS) \ + -DVMLINUX_ENTRY_ADDRESS=$(VMLINUX_ENTRY_ADDRESS) \ + -DADDR_BITS=$(ADDR_BITS) \ + -DADDR_CELLS=$(itb_addr_cells) + +$(obj)/vmlinux.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE + $(call if_changed,cpp_its_S,none,vmlinux.bin) + +$(obj)/vmlinux.gz.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE + $(call if_changed,cpp_its_S,gzip,vmlinux.bin.gz) + +$(obj)/vmlinux.bz2.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE + $(call if_changed,cpp_its_S,bzip2,vmlinux.bin.bz2) + +$(obj)/vmlinux.lzma.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE + $(call if_changed,cpp_its_S,lzma,vmlinux.bin.lzma) + +$(obj)/vmlinux.lzo.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE + $(call if_changed,cpp_its_S,lzo,vmlinux.bin.lzo) + +targets += vmlinux.itb +targets += vmlinux.gz.itb +targets += vmlinux.bz2.itb +targets += vmlinux.lzma.itb +targets += vmlinux.lzo.itb + +quiet_cmd_itb-image = ITB $@ + cmd_itb-image = \ + env PATH="$(objtree)/scripts/dtc:$(PATH)" \ + $(BASH) $(MKIMAGE) \ + -D "-I dts -O dtb -p 500 \ + --include $(objtree)/arch/mips \ + --warning no-unit_address_vs_reg" \ + -f $(2) $@ + +$(obj)/vmlinux.itb: $(obj)/vmlinux.its $(obj)/vmlinux.bin FORCE + $(call if_changed,itb-image,$<) + +$(obj)/vmlinux.%.itb: $(obj)/vmlinux.%.its $(obj)/vmlinux.bin.% FORCE + $(call if_changed,itb-image,$<) + +# for cleaning +subdir- += compressed tools -- cgit v1.3.1