diff options
Diffstat (limited to 'arch/x86/include/asm/intel_rdt.h')
| -rw-r--r-- | arch/x86/include/asm/intel_rdt.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h index 2e5eab09083e..5bc72a4dbd5e 100644 --- a/arch/x86/include/asm/intel_rdt.h +++ b/arch/x86/include/asm/intel_rdt.h @@ -1,8 +1,12 @@ #ifndef _ASM_X86_INTEL_RDT_H #define _ASM_X86_INTEL_RDT_H +#ifdef CONFIG_INTEL_RDT_A + #include <linux/jump_label.h> +#include <asm/intel_rdt_common.h> + #define IA32_L3_QOS_CFG 0xc81 #define IA32_L3_CBM_BASE 0xc90 #define IA32_L2_CBM_BASE 0xd10 @@ -176,4 +180,42 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off); int rdtgroup_schemata_show(struct kernfs_open_file *of, struct seq_file *s, void *v); + +/* + * intel_rdt_sched_in() - Writes the task's CLOSid to IA32_PQR_MSR + * + * Following considerations are made so that this has minimal impact + * on scheduler hot path: + * - This will stay as no-op unless we are running on an Intel SKU + * which supports resource control and we enable by mounting the + * resctrl file system. + * - Caches the per cpu CLOSid values and does the MSR write only + * when a task with a different CLOSid is scheduled in. + */ +static inline void intel_rdt_sched_in(void) +{ + if (static_branch_likely(&rdt_enable_key)) { + struct intel_pqr_state *state = this_cpu_ptr(&pqr_state); + int closid; + + /* + * If this task has a closid assigned, use it. + * Else use the closid assigned to this cpu. + */ + closid = current->closid; + if (closid == 0) + closid = this_cpu_read(cpu_closid); + + if (closid != state->closid) { + state->closid = closid; + wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, closid); + } + } +} + +#else + +static inline void intel_rdt_sched_in(void) {} + +#endif /* CONFIG_INTEL_RDT_A */ #endif /* _ASM_X86_INTEL_RDT_H */ |