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 --- include/dt-bindings/clock/aspeed-clock.h | 58 ++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 include/dt-bindings/clock/aspeed-clock.h (limited to 'include/dt-bindings/clock/aspeed-clock.h') diff --git a/include/dt-bindings/clock/aspeed-clock.h b/include/dt-bindings/clock/aspeed-clock.h new file mode 100644 index 000000000..671e5a476 --- /dev/null +++ b/include/dt-bindings/clock/aspeed-clock.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */ + +#ifndef DT_BINDINGS_ASPEED_CLOCK_H +#define DT_BINDINGS_ASPEED_CLOCK_H + +#define ASPEED_CLK_GATE_ECLK 0 +#define ASPEED_CLK_GATE_GCLK 1 +#define ASPEED_CLK_GATE_MCLK 2 +#define ASPEED_CLK_GATE_VCLK 3 +#define ASPEED_CLK_GATE_BCLK 4 +#define ASPEED_CLK_GATE_DCLK 5 +#define ASPEED_CLK_GATE_REFCLK 6 +#define ASPEED_CLK_GATE_USBPORT2CLK 7 +#define ASPEED_CLK_GATE_LCLK 8 +#define ASPEED_CLK_GATE_USBUHCICLK 9 +#define ASPEED_CLK_GATE_D1CLK 10 +#define ASPEED_CLK_GATE_YCLK 11 +#define ASPEED_CLK_GATE_USBPORT1CLK 12 +#define ASPEED_CLK_GATE_UART1CLK 13 +#define ASPEED_CLK_GATE_UART2CLK 14 +#define ASPEED_CLK_GATE_UART5CLK 15 +#define ASPEED_CLK_GATE_ESPICLK 16 +#define ASPEED_CLK_GATE_MAC1CLK 17 +#define ASPEED_CLK_GATE_MAC2CLK 18 +#define ASPEED_CLK_GATE_RSACLK 19 +#define ASPEED_CLK_GATE_UART3CLK 20 +#define ASPEED_CLK_GATE_UART4CLK 21 +#define ASPEED_CLK_GATE_SDCLK 22 +#define ASPEED_CLK_GATE_LHCCLK 23 +#define ASPEED_CLK_HPLL 24 +#define ASPEED_CLK_AHB 25 +#define ASPEED_CLK_APB 26 +#define ASPEED_CLK_UART 27 +#define ASPEED_CLK_SDIO 28 +#define ASPEED_CLK_ECLK 29 +#define ASPEED_CLK_ECLK_MUX 30 +#define ASPEED_CLK_LHCLK 31 +#define ASPEED_CLK_MAC 32 +#define ASPEED_CLK_BCLK 33 +#define ASPEED_CLK_MPLL 34 +#define ASPEED_CLK_24M 35 +#define ASPEED_CLK_MAC1RCLK 36 +#define ASPEED_CLK_MAC2RCLK 37 + +#define ASPEED_RESET_XDMA 0 +#define ASPEED_RESET_MCTP 1 +#define ASPEED_RESET_ADC 2 +#define ASPEED_RESET_JTAG_MASTER 3 +#define ASPEED_RESET_MIC 4 +#define ASPEED_RESET_PWM 5 +#define ASPEED_RESET_PECI 6 +#define ASPEED_RESET_I2C 7 +#define ASPEED_RESET_AHB 8 +#define ASPEED_RESET_CRT1 9 +#define ASPEED_RESET_HACE 10 +#define ASPEED_RESET_VIDEO 11 + +#endif -- cgit v1.3.1