diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/arm_mpam.h | 32 | ||||
| -rw-r--r-- | include/linux/entry-common.h | 2 | ||||
| -rw-r--r-- | include/linux/irq-entry-common.h | 256 |
3 files changed, 235 insertions, 55 deletions
diff --git a/include/linux/arm_mpam.h b/include/linux/arm_mpam.h index 7f00c5285a32..f92a36187a52 100644 --- a/include/linux/arm_mpam.h +++ b/include/linux/arm_mpam.h @@ -5,6 +5,7 @@ #define __LINUX_ARM_MPAM_H #include <linux/acpi.h> +#include <linux/resctrl_types.h> #include <linux/types.h> struct mpam_msc; @@ -49,6 +50,37 @@ static inline int mpam_ris_create(struct mpam_msc *msc, u8 ris_idx, } #endif +bool resctrl_arch_alloc_capable(void); +bool resctrl_arch_mon_capable(void); + +void resctrl_arch_set_cpu_default_closid(int cpu, u32 closid); +void resctrl_arch_set_closid_rmid(struct task_struct *tsk, u32 closid, u32 rmid); +void resctrl_arch_set_cpu_default_closid_rmid(int cpu, u32 closid, u32 rmid); +void resctrl_arch_sched_in(struct task_struct *tsk); +bool resctrl_arch_match_closid(struct task_struct *tsk, u32 closid); +bool resctrl_arch_match_rmid(struct task_struct *tsk, u32 closid, u32 rmid); +u32 resctrl_arch_rmid_idx_encode(u32 closid, u32 rmid); +void resctrl_arch_rmid_idx_decode(u32 idx, u32 *closid, u32 *rmid); +u32 resctrl_arch_system_num_rmid_idx(void); + +struct rdt_resource; +void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, enum resctrl_event_id evtid); +void resctrl_arch_mon_ctx_free(struct rdt_resource *r, enum resctrl_event_id evtid, void *ctx); + +/* + * The CPU configuration for MPAM is cheap to write, and is only written if it + * has changed. No need for fine grained enables. + */ +static inline void resctrl_arch_enable_mon(void) { } +static inline void resctrl_arch_disable_mon(void) { } +static inline void resctrl_arch_enable_alloc(void) { } +static inline void resctrl_arch_disable_alloc(void) { } + +static inline unsigned int resctrl_arch_round_mon_val(unsigned int val) +{ + return val; +} + /** * mpam_register_requestor() - Register a requestor with the MPAM driver * @partid_max: The maximum PARTID value the requestor can generate. diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index f83ca0abf2cd..dbaa153100f4 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -321,7 +321,7 @@ static __always_inline void syscall_exit_to_user_mode(struct pt_regs *regs) { instrumentation_begin(); syscall_exit_to_user_mode_work(regs); - local_irq_disable_exit_to_user(); + local_irq_disable(); syscall_exit_to_user_mode_prepare(regs); instrumentation_end(); exit_to_user_mode(); diff --git a/include/linux/irq-entry-common.h b/include/linux/irq-entry-common.h index d26d1b1bcbfb..384520217bfe 100644 --- a/include/linux/irq-entry-common.h +++ b/include/linux/irq-entry-common.h @@ -101,37 +101,6 @@ static __always_inline void enter_from_user_mode(struct pt_regs *regs) } /** - * local_irq_enable_exit_to_user - Exit to user variant of local_irq_enable() - * @ti_work: Cached TIF flags gathered with interrupts disabled - * - * Defaults to local_irq_enable(). Can be supplied by architecture specific - * code. - */ -static inline void local_irq_enable_exit_to_user(unsigned long ti_work); - -#ifndef local_irq_enable_exit_to_user -static __always_inline void local_irq_enable_exit_to_user(unsigned long ti_work) -{ - local_irq_enable(); -} -#endif - -/** - * local_irq_disable_exit_to_user - Exit to user variant of local_irq_disable() - * - * Defaults to local_irq_disable(). Can be supplied by architecture specific - * code. - */ -static inline void local_irq_disable_exit_to_user(void); - -#ifndef local_irq_disable_exit_to_user -static __always_inline void local_irq_disable_exit_to_user(void) -{ - local_irq_disable(); -} -#endif - -/** * arch_exit_to_user_mode_work - Architecture specific TIF work for exit * to user mode. * @regs: Pointer to currents pt_regs @@ -335,6 +304,8 @@ static __always_inline void irqentry_enter_from_user_mode(struct pt_regs *regs) */ static __always_inline void irqentry_exit_to_user_mode(struct pt_regs *regs) { + lockdep_assert_irqs_disabled(); + instrumentation_begin(); irqentry_exit_to_user_mode_prepare(regs); instrumentation_end(); @@ -366,6 +337,205 @@ typedef struct irqentry_state { #endif /** + * irqentry_exit_cond_resched - Conditionally reschedule on return from interrupt + * + * Conditional reschedule with additional sanity checks. + */ +void raw_irqentry_exit_cond_resched(void); + +#ifdef CONFIG_PREEMPT_DYNAMIC +#if defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) +#define irqentry_exit_cond_resched_dynamic_enabled raw_irqentry_exit_cond_resched +#define irqentry_exit_cond_resched_dynamic_disabled NULL +DECLARE_STATIC_CALL(irqentry_exit_cond_resched, raw_irqentry_exit_cond_resched); +#define irqentry_exit_cond_resched() static_call(irqentry_exit_cond_resched)() +#elif defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) +DECLARE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); +void dynamic_irqentry_exit_cond_resched(void); +#define irqentry_exit_cond_resched() dynamic_irqentry_exit_cond_resched() +#endif +#else /* CONFIG_PREEMPT_DYNAMIC */ +#define irqentry_exit_cond_resched() raw_irqentry_exit_cond_resched() +#endif /* CONFIG_PREEMPT_DYNAMIC */ + +/** + * irqentry_enter_from_kernel_mode - Establish state before invoking the irq handler + * @regs: Pointer to currents pt_regs + * + * Invoked from architecture specific entry code with interrupts disabled. + * Can only be called when the interrupt entry came from kernel mode. The + * calling code must be non-instrumentable. When the function returns all + * state is correct and the subsequent functions can be instrumented. + * + * The function establishes state (lockdep, RCU (context tracking), tracing) and + * is provided for architectures which require a strict split between entry from + * kernel and user mode and therefore cannot use irqentry_enter() which handles + * both entry modes. + * + * Returns: An opaque object that must be passed to irqentry_exit_to_kernel_mode(). + */ +static __always_inline irqentry_state_t irqentry_enter_from_kernel_mode(struct pt_regs *regs) +{ + irqentry_state_t ret = { + .exit_rcu = false, + }; + + /* + * If this entry hit the idle task invoke ct_irq_enter() whether + * RCU is watching or not. + * + * Interrupts can nest when the first interrupt invokes softirq + * processing on return which enables interrupts. + * + * Scheduler ticks in the idle task can mark quiescent state and + * terminate a grace period, if and only if the timer interrupt is + * not nested into another interrupt. + * + * Checking for rcu_is_watching() here would prevent the nesting + * interrupt to invoke ct_irq_enter(). If that nested interrupt is + * the tick then rcu_flavor_sched_clock_irq() would wrongfully + * assume that it is the first interrupt and eventually claim + * quiescent state and end grace periods prematurely. + * + * Unconditionally invoke ct_irq_enter() so RCU state stays + * consistent. + * + * TINY_RCU does not support EQS, so let the compiler eliminate + * this part when enabled. + */ + if (!IS_ENABLED(CONFIG_TINY_RCU) && + (is_idle_task(current) || arch_in_rcu_eqs())) { + /* + * If RCU is not watching then the same careful + * sequence vs. lockdep and tracing is required + * as in irqentry_enter_from_user_mode(). + */ + lockdep_hardirqs_off(CALLER_ADDR0); + ct_irq_enter(); + instrumentation_begin(); + kmsan_unpoison_entry_regs(regs); + trace_hardirqs_off_finish(); + instrumentation_end(); + + ret.exit_rcu = true; + return ret; + } + + /* + * If RCU is watching then RCU only wants to check whether it needs + * to restart the tick in NOHZ mode. rcu_irq_enter_check_tick() + * already contains a warning when RCU is not watching, so no point + * in having another one here. + */ + lockdep_hardirqs_off(CALLER_ADDR0); + instrumentation_begin(); + kmsan_unpoison_entry_regs(regs); + rcu_irq_enter_check_tick(); + trace_hardirqs_off_finish(); + instrumentation_end(); + + return ret; +} + +/** + * irqentry_exit_to_kernel_mode_preempt - Run preempt checks on return to kernel mode + * @regs: Pointer to current's pt_regs + * @state: Return value from matching call to irqentry_enter_from_kernel_mode() + * + * This is to be invoked before irqentry_exit_to_kernel_mode_after_preempt() to + * allow kernel preemption on return from interrupt. + * + * Must be invoked with interrupts disabled and CPU state which allows kernel + * preemption. + * + * After returning from this function, the caller can modify CPU state before + * invoking irqentry_exit_to_kernel_mode_after_preempt(), which is required to + * re-establish the tracing, lockdep and RCU state for returning to the + * interrupted context. + */ +static inline void irqentry_exit_to_kernel_mode_preempt(struct pt_regs *regs, + irqentry_state_t state) +{ + if (regs_irqs_disabled(regs) || state.exit_rcu) + return; + + if (IS_ENABLED(CONFIG_PREEMPTION)) + irqentry_exit_cond_resched(); +} + +/** + * irqentry_exit_to_kernel_mode_after_preempt - Establish trace, lockdep and RCU state + * @regs: Pointer to current's pt_regs + * @state: Return value from matching call to irqentry_enter_from_kernel_mode() + * + * This is to be invoked after irqentry_exit_to_kernel_mode_preempt() and before + * actually returning to the interrupted context. + * + * There are no requirements for the CPU state other than being able to complete + * the tracing, lockdep and RCU state transitions. After this function returns + * the caller must return directly to the interrupted context. + */ +static __always_inline void +irqentry_exit_to_kernel_mode_after_preempt(struct pt_regs *regs, irqentry_state_t state) +{ + if (!regs_irqs_disabled(regs)) { + /* + * If RCU was not watching on entry this needs to be done + * carefully and needs the same ordering of lockdep/tracing + * and RCU as the return to user mode path. + */ + if (state.exit_rcu) { + instrumentation_begin(); + /* Tell the tracer that IRET will enable interrupts */ + trace_hardirqs_on_prepare(); + lockdep_hardirqs_on_prepare(); + instrumentation_end(); + ct_irq_exit(); + lockdep_hardirqs_on(CALLER_ADDR0); + return; + } + + instrumentation_begin(); + /* Covers both tracing and lockdep */ + trace_hardirqs_on(); + instrumentation_end(); + } else { + /* + * IRQ flags state is correct already. Just tell RCU if it + * was not watching on entry. + */ + if (state.exit_rcu) + ct_irq_exit(); + } +} + +/** + * irqentry_exit_to_kernel_mode - Run preempt checks and establish state after + * invoking the interrupt handler + * @regs: Pointer to current's pt_regs + * @state: Return value from matching call to irqentry_enter_from_kernel_mode() + * + * This is the counterpart of irqentry_enter_from_kernel_mode() and combines + * the calls to irqentry_exit_to_kernel_mode_preempt() and + * irqentry_exit_to_kernel_mode_after_preempt(). + * + * The requirement for the CPU state is that it can schedule. After the function + * returns the tracing, lockdep and RCU state transitions are completed and the + * caller must return directly to the interrupted context. + */ +static __always_inline void irqentry_exit_to_kernel_mode(struct pt_regs *regs, + irqentry_state_t state) +{ + lockdep_assert_irqs_disabled(); + + instrumentation_begin(); + irqentry_exit_to_kernel_mode_preempt(regs, state); + instrumentation_end(); + + irqentry_exit_to_kernel_mode_after_preempt(regs, state); +} + +/** * irqentry_enter - Handle state tracking on ordinary interrupt entries * @regs: Pointer to pt_regs of interrupted context * @@ -394,33 +564,11 @@ typedef struct irqentry_state { * establish the proper context for NOHZ_FULL. Otherwise scheduling on exit * would not be possible. * - * Returns: An opaque object that must be passed to idtentry_exit() + * Returns: An opaque object that must be passed to irqentry_exit() */ irqentry_state_t noinstr irqentry_enter(struct pt_regs *regs); /** - * irqentry_exit_cond_resched - Conditionally reschedule on return from interrupt - * - * Conditional reschedule with additional sanity checks. - */ -void raw_irqentry_exit_cond_resched(void); - -#ifdef CONFIG_PREEMPT_DYNAMIC -#if defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) -#define irqentry_exit_cond_resched_dynamic_enabled raw_irqentry_exit_cond_resched -#define irqentry_exit_cond_resched_dynamic_disabled NULL -DECLARE_STATIC_CALL(irqentry_exit_cond_resched, raw_irqentry_exit_cond_resched); -#define irqentry_exit_cond_resched() static_call(irqentry_exit_cond_resched)() -#elif defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) -DECLARE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); -void dynamic_irqentry_exit_cond_resched(void); -#define irqentry_exit_cond_resched() dynamic_irqentry_exit_cond_resched() -#endif -#else /* CONFIG_PREEMPT_DYNAMIC */ -#define irqentry_exit_cond_resched() raw_irqentry_exit_cond_resched() -#endif /* CONFIG_PREEMPT_DYNAMIC */ - -/** * irqentry_exit - Handle return from exception that used irqentry_enter() * @regs: Pointer to pt_regs (exception entry regs) * @state: Return value from matching call to irqentry_enter() |
