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/crypto/ccp/sp-dev.h | 190 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 190 insertions(+) create mode 100644 drivers/crypto/ccp/sp-dev.h (limited to 'drivers/crypto/ccp/sp-dev.h') diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h new file mode 100644 index 000000000..a83751cfd --- /dev/null +++ b/drivers/crypto/ccp/sp-dev.h @@ -0,0 +1,190 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * AMD Secure Processor driver + * + * Copyright (C) 2017-2019 Advanced Micro Devices, Inc. + * + * Author: Tom Lendacky + * Author: Gary R Hook + * Author: Brijesh Singh + */ + +#ifndef __SP_DEV_H__ +#define __SP_DEV_H__ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define SP_MAX_NAME_LEN 32 + +#define CACHE_NONE 0x00 +#define CACHE_WB_NO_ALLOC 0xb7 + +#define PLATFORM_FEATURE_DBC 0x1 +#define PLATFORM_FEATURE_HSTI 0x2 + +#define PSP_FEATURE(psp, feat) (psp->vdata && psp->vdata->platform_features & PLATFORM_FEATURE_##feat) + +/* Structure to hold CCP device data */ +struct ccp_device; +struct ccp_vdata { + const unsigned int version; + const unsigned int dma_chan_attr; + void (*setup)(struct ccp_device *); + const struct ccp_actions *perform; + const unsigned int offset; + const unsigned int rsamax; +}; + +struct sev_vdata { + const unsigned int cmdresp_reg; + const unsigned int cmdbuff_addr_lo_reg; + const unsigned int cmdbuff_addr_hi_reg; +}; + +struct tee_vdata { + const unsigned int cmdresp_reg; + const unsigned int cmdbuff_addr_lo_reg; + const unsigned int cmdbuff_addr_hi_reg; + const unsigned int ring_wptr_reg; + const unsigned int ring_rptr_reg; + const unsigned int info_reg; +}; + +struct platform_access_vdata { + const unsigned int cmdresp_reg; + const unsigned int cmdbuff_addr_lo_reg; + const unsigned int cmdbuff_addr_hi_reg; + const unsigned int doorbell_button_reg; + const unsigned int doorbell_cmd_reg; + +}; + +struct psp_vdata { + const struct sev_vdata *sev; + const struct tee_vdata *tee; + const struct platform_access_vdata *platform_access; + const unsigned int cmdresp_reg; + const unsigned int cmdbuff_addr_lo_reg; + const unsigned int cmdbuff_addr_hi_reg; + const unsigned int feature_reg; + const unsigned int inten_reg; + const unsigned int intsts_reg; + const unsigned int bootloader_info_reg; + const unsigned int platform_features; +}; + +/* Structure to hold SP device data */ +struct sp_dev_vdata { + const unsigned int bar; + + const struct ccp_vdata *ccp_vdata; + const struct psp_vdata *psp_vdata; +}; + +struct sp_device { + struct list_head entry; + + struct device *dev; + + const struct sp_dev_vdata *dev_vdata; + unsigned int ord; + char name[SP_MAX_NAME_LEN]; + + /* Bus specific device information */ + void *dev_specific; + + /* I/O area used for device communication. */ + void __iomem *io_map; + + /* DMA caching attribute support */ + unsigned int axcache; + + /* get and set master device */ + struct sp_device*(*get_psp_master_device)(void); + void (*set_psp_master_device)(struct sp_device *); + void (*clear_psp_master_device)(struct sp_device *); + + bool irq_registered; + bool use_tasklet; + + unsigned int ccp_irq; + irq_handler_t ccp_irq_handler; + void *ccp_irq_data; + + unsigned int psp_irq; + irq_handler_t psp_irq_handler; + void *psp_irq_data; + + void *ccp_data; + void *psp_data; +}; + +int sp_pci_init(void); +void sp_pci_exit(void); + +int sp_platform_init(void); +void sp_platform_exit(void); + +struct sp_device *sp_alloc_struct(struct device *dev); + +int sp_init(struct sp_device *sp); +void sp_destroy(struct sp_device *sp); + +int sp_suspend(struct sp_device *sp); +int sp_resume(struct sp_device *sp); +int sp_restore(struct sp_device *sp); +int sp_request_ccp_irq(struct sp_device *sp, irq_handler_t handler, + const char *name, void *data); +void sp_free_ccp_irq(struct sp_device *sp, void *data); +int sp_request_psp_irq(struct sp_device *sp, irq_handler_t handler, + const char *name, void *data); +void sp_free_psp_irq(struct sp_device *sp, void *data); +struct sp_device *sp_get_psp_master_device(void); + +#ifdef CONFIG_CRYPTO_DEV_SP_CCP + +int ccp_dev_init(struct sp_device *sp); +void ccp_dev_destroy(struct sp_device *sp); + +void ccp_dev_suspend(struct sp_device *sp); +void ccp_dev_resume(struct sp_device *sp); + +#else /* !CONFIG_CRYPTO_DEV_SP_CCP */ + +static inline int ccp_dev_init(struct sp_device *sp) +{ + return 0; +} +static inline void ccp_dev_destroy(struct sp_device *sp) { } +static inline void ccp_dev_suspend(struct sp_device *sp) { } +static inline void ccp_dev_resume(struct sp_device *sp) { } +#endif /* CONFIG_CRYPTO_DEV_SP_CCP */ + +#ifdef CONFIG_CRYPTO_DEV_SP_PSP + +int psp_dev_init(struct sp_device *sp); +void psp_pci_init(void); +void psp_dev_destroy(struct sp_device *sp); +void psp_pci_exit(void); +int psp_restore(struct sp_device *sp); + +#else /* !CONFIG_CRYPTO_DEV_SP_PSP */ + +static inline int psp_dev_init(struct sp_device *sp) { return 0; } +static inline void psp_pci_init(void) { } +static inline void psp_dev_destroy(struct sp_device *sp) { } +static inline void psp_pci_exit(void) { } +static inline int psp_restore(struct sp_device *sp) { return 0; } + +#endif /* CONFIG_CRYPTO_DEV_SP_PSP */ + +#endif -- cgit v1.3.1