From 556d2892aa715286d840a74216c8fff885559261 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Wed, 12 Nov 2025 18:57:30 -0600 Subject: x86,fs/resctrl: Implement "io_alloc" enable/disable handlers "io_alloc" is the generic name of the new resctrl feature that enables system software to configure the portion of cache allocated for I/O traffic. On AMD systems, "io_alloc" resctrl feature is backed by AMD's L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE). Introduce the architecture-specific functions that resctrl fs should call to enable, disable, or check status of the "io_alloc" feature. Change SDCIAE state by setting (to enable) or clearing (to disable) bit 1 of MSR_IA32_L3_QOS_EXT_CFG on all logical processors within the cache domain. Signed-off-by: Babu Moger Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Link: https://patch.msgid.link/9e9070100c320eab5368e088a3642443dee95ed7.1762995456.git.babu.moger@amd.com --- arch/x86/kernel/cpu/resctrl/internal.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86/kernel/cpu/resctrl/internal.h') diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index 9f4c2f0aaf5c..4a916c84a322 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -46,6 +46,9 @@ struct arch_mbm_state { #define ABMC_EXTENDED_EVT_ID BIT(31) #define ABMC_EVT_ID BIT(0) +/* Setting bit 1 in MSR_IA32_L3_QOS_EXT_CFG enables the SDCIAE feature. */ +#define SDCIAE_ENABLE_BIT 1 + /** * struct rdt_hw_ctrl_domain - Arch private attributes of a set of CPUs that share * a resource for a control function @@ -112,6 +115,7 @@ struct msr_param { * @mbm_width: Monitor width, to detect and correct for overflow. * @cdp_enabled: CDP state of this resource * @mbm_cntr_assign_enabled: ABMC feature is enabled + * @sdciae_enabled: SDCIAE feature (backing "io_alloc") is enabled. * * Members of this structure are either private to the architecture * e.g. mbm_width, or accessed via helpers that provide abstraction. e.g. @@ -126,6 +130,7 @@ struct rdt_hw_resource { unsigned int mbm_width; bool cdp_enabled; bool mbm_cntr_assign_enabled; + bool sdciae_enabled; }; static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r) -- cgit v1.2.3