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The currently implemented monitors are: * nomiss: validate dl entities run to completion before their deadiline Reviewed-by: Nam Cao Signed-off-by: Gabriele Monaco --- Notes: V8: * Warn if kallsyms lookup fails * Use u8 instead of uint8_t * Drop throttle monitor, will submit separately Documentation/trace/rv/index.rst | 1 + Documentation/trace/rv/monitor_deadline.rst | 84 +++++ kernel/trace/rv/Kconfig | 4 + kernel/trace/rv/Makefile | 2 + kernel/trace/rv/monitors/deadline/Kconfig | 10 + kernel/trace/rv/monitors/deadline/deadline.c | 44 +++ kernel/trace/rv/monitors/deadline/deadline.h | 202 ++++++++++++ kernel/trace/rv/monitors/nomiss/Kconfig | 15 + kernel/trace/rv/monitors/nomiss/nomiss.c | 293 ++++++++++++++++++ kernel/trace/rv/monitors/nomiss/nomiss.h | 123 ++++++++ .../trace/rv/monitors/nomiss/nomiss_trace.h | 19 ++ kernel/trace/rv/rv_trace.h | 1 + tools/verification/models/deadline/nomiss.dot | 41 +++ 13 files changed, 839 insertions(+) create mode 100644 Documentation/trace/rv/monitor_deadline.rst create mode 100644 kernel/trace/rv/monitors/deadline/Kconfig create mode 100644 kernel/trace/rv/monitors/deadline/deadline.c create mode 100644 kernel/trace/rv/monitors/deadline/deadline.h create mode 100644 kernel/trace/rv/monitors/nomiss/Kconfig create mode 100644 kernel/trace/rv/monitors/nomiss/nomiss.c create mode 100644 kernel/trace/rv/monitors/nomiss/nomiss.h create mode 100644 kernel/trace/rv/monitors/nomiss/nomiss_trace.h create mode 100644 tools/verification/models/deadline/nomiss.dot diff --git a/Documentation/trace/rv/index.rst b/Documentation/trace/rv/index.rst index bf9962f49959..29769f06bb0f 100644 --- a/Documentation/trace/rv/index.rst +++ b/Documentation/trace/rv/index.rst @@ -17,3 +17,4 @@ Runtime Verification monitor_sched.rst monitor_rtapp.rst monitor_stall.rst + monitor_deadline.rst diff --git a/Documentation/trace/rv/monitor_deadline.rst b/Documentation/trace/rv/monitor_deadline.rst new file mode 100644 index 000000000000..84506ed1e293 --- /dev/null +++ b/Documentation/trace/rv/monitor_deadline.rst @@ -0,0 +1,84 @@ +Deadline monitors +================= + +- Name: deadline +- Type: container for multiple monitors +- Author: Gabriele Monaco + +Description +----------- + +The deadline monitor is a set of specifications to describe the deadline +scheduler behaviour. It includes monitors per scheduling entity (deadline tasks +and servers) that work independently to verify different specifications the +deadline scheduler should follow. + +Specifications +-------------- + +Monitor nomiss +~~~~~~~~~~~~~~ + +The nomiss monitor ensures dl entities get to run *and* run to completion +before their deadline, although deferrable servers may not run. An entity is +considered done if ``throttled``, either because it yielded or used up its +runtime, or when it voluntarily starts ``sleeping``. +The monitor includes a user configurable deadline threshold. If the total +utilisation of deadline tasks is larger than 1, they are only guaranteed +bounded tardiness. See Documentation/scheduler/sched-deadline.rst for more +details. The threshold (module parameter ``nomiss.deadline_thresh``) can be +configured to avoid the monitor to fail based on the acceptable tardiness in +the system. Since ``dl_throttle`` is a valid outcome for the entity to be done, +the minimum tardiness needs be 1 tick to consider the throttle delay, unless +the ``HRTICK_DL`` scheduler feature is active. + +Servers have also an intermediate ``idle`` state, occurring as soon as no +runnable task is available from ready or running where no timing constraint +is applied. A server goes to sleep by stopping, there is no wakeup equivalent +as the order of a server starting and replenishing is not defined, hence a +server can run from sleeping without being ready:: + + | + sched_wakeup v + dl_replenish;reset(clk) -- #=========================# + | H H dl_replenish;reset(clk) + +-----------> H H <--------------------+ + H H | + +- dl_server_stop ---- H ready H | + | +-----------------> H clk < DEADLINE_NS() H dl_throttle; | + | | H H is_defer == 1 | + | | sched_switch_in - H H -----------------+ | + | | | #=========================# | | + | | | | ^ | | + | | | dl_server_idle dl_replenish;reset(clk) | | + | | | v | | | + | | | +--------------+ | | + | | | +------ | | | | + | | | dl_server_idle | | dl_throttle | | + | | | | | idle | -----------------+ | | + | | | +-----> | | | | | + | | | | | | | | + | | | | | | | | + +--+--+---+--- dl_server_stop -- +--------------+ | | | + | | | | | ^ | | | + | | | | sched_switch_in dl_server_idle | | | + | | | | v | | | | + | | | | +---------- +---------------------+ | | | + | | | | sched_switch_in | | | | | + | | | | sched_wakeup | | | | | + | | | | dl_replenish; | running | -------+ | | | + | | | | reset(clk) | clk < DEADLINE_NS() | | | | | + | | | | +---------> | | dl_throttle | | | + | | | +----------------> | | | | | | + | | | +---------------------+ | | | | + | | sched_wakeup ^ sched_switch_suspend | | | | + v v dl_replenish;reset(clk) | dl_server_stop | | | | + +--------------+ | | v v v | + | | - sched_switch_in + | +---------------+ + | | <---------------------+ dl_throttle +-- | | + | sleeping | sched_wakeup | | throttled | + | | -- dl_server_stop dl_server_idle +-> | | + | | dl_server_idle sched_switch_suspend +---------------+ + +--------------+ <---------+ ^ + | | + +------ dl_throttle;is_constr_dl == 1 || is_defer == 1 ------+ diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig index 720fbe4935f8..3884b14df375 100644 --- a/kernel/trace/rv/Kconfig +++ b/kernel/trace/rv/Kconfig @@ -79,6 +79,10 @@ source "kernel/trace/rv/monitors/sleep/Kconfig" # Add new rtapp monitors here source "kernel/trace/rv/monitors/stall/Kconfig" +source "kernel/trace/rv/monitors/deadline/Kconfig" +source "kernel/trace/rv/monitors/nomiss/Kconfig" +# Add new deadline monitors here + # Add new monitors here config RV_REACTORS diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile index 51c95e2d2da6..94498da35b37 100644 --- a/kernel/trace/rv/Makefile +++ b/kernel/trace/rv/Makefile @@ -18,6 +18,8 @@ obj-$(CONFIG_RV_MON_NRP) += monitors/nrp/nrp.o obj-$(CONFIG_RV_MON_SSSW) += monitors/sssw/sssw.o obj-$(CONFIG_RV_MON_OPID) += monitors/opid/opid.o obj-$(CONFIG_RV_MON_STALL) += monitors/stall/stall.o +obj-$(CONFIG_RV_MON_DEADLINE) += monitors/deadline/deadline.o +obj-$(CONFIG_RV_MON_NOMISS) += monitors/nomiss/nomiss.o # Add new monitors here obj-$(CONFIG_RV_REACTORS) += rv_reactors.o obj-$(CONFIG_RV_REACT_PRINTK) += reactor_printk.o diff --git a/kernel/trace/rv/monitors/deadline/Kconfig b/kernel/trace/rv/monitors/deadline/Kconfig new file mode 100644 index 000000000000..38804a6ad91d --- /dev/null +++ b/kernel/trace/rv/monitors/deadline/Kconfig @@ -0,0 +1,10 @@ +config RV_MON_DEADLINE + depends on RV + bool "deadline monitor" + help + Collection of monitors to check the deadline scheduler and server + behave according to specifications. Enable this to enable all + scheduler specification supported by the current kernel. + + For further information, see: + Documentation/trace/rv/monitor_deadline.rst diff --git a/kernel/trace/rv/monitors/deadline/deadline.c b/kernel/trace/rv/monitors/deadline/deadline.c new file mode 100644 index 000000000000..d566d4542ebf --- /dev/null +++ b/kernel/trace/rv/monitors/deadline/deadline.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +#define MODULE_NAME "deadline" + +#include "deadline.h" + +struct rv_monitor rv_deadline = { + .name = "deadline", + .description = "container for several deadline scheduler specifications.", + .enable = NULL, + .disable = NULL, + .reset = NULL, + .enabled = 0, +}; + +/* Used by other monitors */ +struct sched_class *rv_ext_sched_class; + +static int __init register_deadline(void) +{ + if (IS_ENABLED(CONFIG_SCHED_CLASS_EXT)) { + rv_ext_sched_class = (void *)kallsyms_lookup_name("ext_sched_class"); + if (!rv_ext_sched_class) + pr_warn("rv: Missing ext_sched_class, monitors may not work.\n"); + } + return rv_register_monitor(&rv_deadline, NULL); +} + +static void __exit unregister_deadline(void) +{ + rv_unregister_monitor(&rv_deadline); +} + +module_init(register_deadline); +module_exit(unregister_deadline); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Gabriele Monaco "); +MODULE_DESCRIPTION("deadline: container for several deadline scheduler specifications."); diff --git a/kernel/trace/rv/monitors/deadline/deadline.h b/kernel/trace/rv/monitors/deadline/deadline.h new file mode 100644 index 000000000000..0bbfd2543329 --- /dev/null +++ b/kernel/trace/rv/monitors/deadline/deadline.h @@ -0,0 +1,202 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include +#include +#include +#include +#include +#include + +/* + * Dummy values if not available + */ +#ifndef __NR_sched_setscheduler +#define __NR_sched_setscheduler -__COUNTER__ +#endif +#ifndef __NR_sched_setattr +#define __NR_sched_setattr -__COUNTER__ +#endif + +extern struct rv_monitor rv_deadline; +/* Initialised when registering the deadline container */ +extern struct sched_class *rv_ext_sched_class; + +/* + * If both have dummy values, the syscalls are not supported and we don't even + * need to register the handler. + */ +static inline bool should_skip_syscall_handle(void) +{ + return __NR_sched_setattr < 0 && __NR_sched_setscheduler < 0; +} + +/* + * is_supported_type - return true if @type is supported by the deadline monitors + */ +static inline bool is_supported_type(u8 type) +{ + return type == DL_TASK || type == DL_SERVER_FAIR || type == DL_SERVER_EXT; +} + +/* + * is_server_type - return true if @type is a supported server + */ +static inline bool is_server_type(u8 type) +{ + return is_supported_type(type) && type != DL_TASK; +} + +/* + * Use negative numbers for the server. + * Currently only one fair server per CPU, may change in the future. + */ +#define fair_server_id(cpu) (-cpu) +#define ext_server_id(cpu) (-cpu - num_possible_cpus()) +#define NO_SERVER_ID (-2 * num_possible_cpus()) +/* + * Get a unique id used for dl entities + * + * The cpu is not required for tasks as the pid is used there, if this function + * is called on a dl_se that for sure corresponds to a task, DL_TASK can be + * used in place of cpu. + * We need the cpu for servers as it is provided in the tracepoint and we + * cannot easily retrieve it from the dl_se (requires the struct rq definition). + */ +static inline int get_entity_id(struct sched_dl_entity *dl_se, int cpu, u8 type) +{ + if (dl_server(dl_se) && type != DL_TASK) { + if (type == DL_SERVER_FAIR) + return fair_server_id(cpu); + if (type == DL_SERVER_EXT) + return ext_server_id(cpu); + return NO_SERVER_ID; + } + return dl_task_of(dl_se)->pid; +} + +static inline bool task_is_scx_enabled(struct task_struct *tsk) +{ + return IS_ENABLED(CONFIG_SCHED_CLASS_EXT) && + tsk->sched_class == rv_ext_sched_class; +} + +/* Expand id and target as arguments for da functions */ +#define EXPAND_ID(dl_se, cpu, type) get_entity_id(dl_se, cpu, type), dl_se +#define EXPAND_ID_TASK(tsk) get_entity_id(&tsk->dl, task_cpu(tsk), DL_TASK), &tsk->dl + +static inline u8 get_server_type(struct task_struct *tsk) +{ + if (tsk->policy == SCHED_NORMAL || tsk->policy == SCHED_EXT || + tsk->policy == SCHED_BATCH || tsk->policy == SCHED_IDLE) + return task_is_scx_enabled(tsk) ? DL_SERVER_EXT : DL_SERVER_FAIR; + return DL_OTHER; +} + +static inline int extract_params(struct pt_regs *regs, long id, pid_t *pid_out) +{ + size_t size = offsetofend(struct sched_attr, sched_flags); + struct sched_attr __user *uattr, attr; + int new_policy = -1, ret; + unsigned long args[6]; + + switch (id) { + case __NR_sched_setscheduler: + syscall_get_arguments(current, regs, args); + *pid_out = args[0]; + new_policy = args[1]; + break; + case __NR_sched_setattr: + syscall_get_arguments(current, regs, args); + *pid_out = args[0]; + uattr = (struct sched_attr __user *)args[1]; + /* + * Just copy up to sched_flags, we are not interested after that + */ + ret = copy_struct_from_user(&attr, size, uattr, size); + if (ret) + return ret; + if (attr.sched_flags & SCHED_FLAG_KEEP_POLICY) + return -EINVAL; + new_policy = attr.sched_policy; + break; + default: + return -EINVAL; + } + + return new_policy & ~SCHED_RESET_ON_FORK; +} + +/* Helper functions requiring DA/HA utilities */ +#ifdef RV_MON_TYPE + +/* + * get_fair_server - get the fair server associated to a task + * + * If the task is a boosted task, the server is available in the task_struct, + * otherwise grab the dl entity saved for the CPU where the task is enqueued. + * This function assumes the task is enqueued somewhere. + */ +static inline struct sched_dl_entity *get_server(struct task_struct *tsk, u8 type) +{ + if (tsk->dl_server && get_server_type(tsk) == type) + return tsk->dl_server; + if (type == DL_SERVER_FAIR) + return da_get_target_by_id(fair_server_id(task_cpu(tsk))); + if (type == DL_SERVER_EXT) + return da_get_target_by_id(ext_server_id(task_cpu(tsk))); + return NULL; +} + +/* + * Initialise monitors for all tasks and pre-allocate the storage for servers. + * This is necessary since we don't have access to the servers here and + * allocation can cause deadlocks from their tracepoints. We can only fill + * pre-initialised storage from there. + */ +static inline int init_storage(bool skip_tasks) +{ + struct task_struct *g, *p; + int cpu; + + for_each_possible_cpu(cpu) { + if (!da_create_empty_storage(fair_server_id(cpu))) + goto fail; + if (IS_ENABLED(CONFIG_SCHED_CLASS_EXT) && + !da_create_empty_storage(ext_server_id(cpu))) + goto fail; + } + + if (skip_tasks) + return 0; + + read_lock(&tasklist_lock); + for_each_process_thread(g, p) { + if (p->policy == SCHED_DEADLINE) { + if (!da_create_storage(EXPAND_ID_TASK(p), NULL)) { + read_unlock(&tasklist_lock); + goto fail; + } + } + } + read_unlock(&tasklist_lock); + return 0; + +fail: + da_monitor_destroy(); + return -ENOMEM; +} + +static void __maybe_unused handle_newtask(void *data, struct task_struct *task, u64 flags) +{ + /* Might be superfluous as tasks are not started with this policy.. */ + if (task->policy == SCHED_DEADLINE) + da_create_storage(EXPAND_ID_TASK(task), NULL); +} + +static void __maybe_unused handle_exit(void *data, struct task_struct *p, bool group_dead) +{ + if (p->policy == SCHED_DEADLINE) + da_destroy_storage(get_entity_id(&p->dl, DL_TASK, DL_TASK)); +} + +#endif diff --git a/kernel/trace/rv/monitors/nomiss/Kconfig b/kernel/trace/rv/monitors/nomiss/Kconfig new file mode 100644 index 000000000000..e1886c3a0dd9 --- /dev/null +++ b/kernel/trace/rv/monitors/nomiss/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +config RV_MON_NOMISS + depends on RV + depends on HAVE_SYSCALL_TRACEPOINTS + depends on RV_MON_DEADLINE + default y + select HA_MON_EVENTS_ID + bool "nomiss monitor" + help + Monitor to ensure dl entities run to completion before their deadiline. + This monitor is part of the deadline monitors collection. + + For further information, see: + Documentation/trace/rv/monitor_deadline.rst diff --git a/kernel/trace/rv/monitors/nomiss/nomiss.c b/kernel/trace/rv/monitors/nomiss/nomiss.c new file mode 100644 index 000000000000..31f90f3638d8 --- /dev/null +++ b/kernel/trace/rv/monitors/nomiss/nomiss.c @@ -0,0 +1,293 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +#define MODULE_NAME "nomiss" + +#include +#include +#include +#include +#include + +#define RV_MON_TYPE RV_MON_PER_OBJ +#define HA_TIMER_TYPE HA_TIMER_WHEEL +/* The start condition is on sched_switch, it's dangerous to allocate there */ +#define DA_SKIP_AUTO_ALLOC +typedef struct sched_dl_entity *monitor_target; +#include "nomiss.h" +#include +#include + +/* + * User configurable deadline threshold. If the total utilisation of deadline + * tasks is larger than 1, they are only guaranteed bounded tardiness. See + * Documentation/scheduler/sched-deadline.rst for more details. + * The minimum tardiness without sched_feat(HRTICK_DL) is 1 tick to accommodate + * for throttle enforced on the next tick. + */ +static u64 deadline_thresh = TICK_NSEC; +module_param(deadline_thresh, ullong, 0644); +#define DEADLINE_NS(ha_mon) (ha_get_target(ha_mon)->dl_deadline + deadline_thresh) + +static u64 ha_get_env(struct ha_monitor *ha_mon, enum envs_nomiss env, u64 time_ns) +{ + if (env == clk_nomiss) + return ha_get_clk_ns(ha_mon, env, time_ns); + else if (env == is_constr_dl_nomiss) + return !dl_is_implicit(ha_get_target(ha_mon)); + else if (env == is_defer_nomiss) + return ha_get_target(ha_mon)->dl_defer; + return ENV_INVALID_VALUE; +} + +static void ha_reset_env(struct ha_monitor *ha_mon, enum envs_nomiss env, u64 time_ns) +{ + if (env == clk_nomiss) + ha_reset_clk_ns(ha_mon, env, time_ns); +} + +static inline bool ha_verify_invariants(struct ha_monitor *ha_mon, + enum states curr_state, enum events event, + enum states next_state, u64 time_ns) +{ + if (curr_state == ready_nomiss) + return ha_check_invariant_ns(ha_mon, clk_nomiss, time_ns); + else if (curr_state == running_nomiss) + return ha_check_invariant_ns(ha_mon, clk_nomiss, time_ns); + return true; +} + +static inline void ha_convert_inv_guard(struct ha_monitor *ha_mon, + enum states curr_state, enum events event, + enum states next_state, u64 time_ns) +{ + if (curr_state == next_state) + return; + if (curr_state == ready_nomiss) + ha_inv_to_guard(ha_mon, clk_nomiss, DEADLINE_NS(ha_mon), time_ns); + else if (curr_state == running_nomiss) + ha_inv_to_guard(ha_mon, clk_nomiss, DEADLINE_NS(ha_mon), time_ns); +} + +static inline bool ha_verify_guards(struct ha_monitor *ha_mon, + enum states curr_state, enum events event, + enum states next_state, u64 time_ns) +{ + bool res = true; + + if (curr_state == ready_nomiss && event == dl_replenish_nomiss) + ha_reset_env(ha_mon, clk_nomiss, time_ns); + else if (curr_state == ready_nomiss && event == dl_throttle_nomiss) + res = ha_get_env(ha_mon, is_defer_nomiss, time_ns) == 1ull; + else if (curr_state == idle_nomiss && event == dl_replenish_nomiss) + ha_reset_env(ha_mon, clk_nomiss, time_ns); + else if (curr_state == running_nomiss && event == dl_replenish_nomiss) + ha_reset_env(ha_mon, clk_nomiss, time_ns); + else if (curr_state == sleeping_nomiss && event == dl_replenish_nomiss) + ha_reset_env(ha_mon, clk_nomiss, time_ns); + else if (curr_state == sleeping_nomiss && event == dl_throttle_nomiss) + res = ha_get_env(ha_mon, is_constr_dl_nomiss, time_ns) == 1ull || + ha_get_env(ha_mon, is_defer_nomiss, time_ns) == 1ull; + else if (curr_state == throttled_nomiss && event == dl_replenish_nomiss) + ha_reset_env(ha_mon, clk_nomiss, time_ns); + return res; +} + +static inline void ha_setup_invariants(struct ha_monitor *ha_mon, + enum states curr_state, enum events event, + enum states next_state, u64 time_ns) +{ + if (next_state == curr_state && event != dl_replenish_nomiss) + return; + if (next_state == ready_nomiss) + ha_start_timer_ns(ha_mon, clk_nomiss, DEADLINE_NS(ha_mon), time_ns); + else if (next_state == running_nomiss) + ha_start_timer_ns(ha_mon, clk_nomiss, DEADLINE_NS(ha_mon), time_ns); + else if (curr_state == ready_nomiss) + ha_cancel_timer(ha_mon); + else if (curr_state == running_nomiss) + ha_cancel_timer(ha_mon); +} + +static bool ha_verify_constraint(struct ha_monitor *ha_mon, + enum states curr_state, enum events event, + enum states next_state, u64 time_ns) +{ + if (!ha_verify_invariants(ha_mon, curr_state, event, next_state, time_ns)) + return false; + + ha_convert_inv_guard(ha_mon, curr_state, event, next_state, time_ns); + + if (!ha_verify_guards(ha_mon, curr_state, event, next_state, time_ns)) + return false; + + ha_setup_invariants(ha_mon, curr_state, event, next_state, time_ns); + + return true; +} + +static void handle_dl_replenish(void *data, struct sched_dl_entity *dl_se, + int cpu, u8 type) +{ + if (is_supported_type(type)) + da_handle_event(EXPAND_ID(dl_se, cpu, type), dl_replenish_nomiss); +} + +static void handle_dl_throttle(void *data, struct sched_dl_entity *dl_se, + int cpu, u8 type) +{ + if (is_supported_type(type)) + da_handle_event(EXPAND_ID(dl_se, cpu, type), dl_throttle_nomiss); +} + +static void handle_dl_server_stop(void *data, struct sched_dl_entity *dl_se, + int cpu, u8 type) +{ + /* + * This isn't the standard use of da_handle_start_run_event since this + * event cannot only occur from the initial state. + * It is fine to use here because it always brings to a known state and + * the fact we "pretend" the transition starts from the initial state + * has no side effect. + */ + if (is_supported_type(type)) + da_handle_start_run_event(EXPAND_ID(dl_se, cpu, type), dl_server_stop_nomiss); +} + +static inline void handle_server_switch(struct task_struct *next, int cpu, u8 type) +{ + struct sched_dl_entity *dl_se = get_server(next, type); + + if (dl_se && is_idle_task(next)) + da_handle_event(EXPAND_ID(dl_se, cpu, type), dl_server_idle_nomiss); +} + +static void handle_sched_switch(void *data, bool preempt, + struct task_struct *prev, + struct task_struct *next, + unsigned int prev_state) +{ + int cpu = task_cpu(next); + + if (prev_state != TASK_RUNNING && !preempt && prev->policy == SCHED_DEADLINE) + da_handle_event(EXPAND_ID_TASK(prev), sched_switch_suspend_nomiss); + if (next->policy == SCHED_DEADLINE) + da_handle_start_run_event(EXPAND_ID_TASK(next), sched_switch_in_nomiss); + + /* + * The server is available in next only if the next task is boosted, + * otherwise we need to retrieve it. + * Here the server continues in the state running/armed until actually + * stopped, this works since we continue expecting a throttle. + */ + if (next->dl_server) + da_handle_start_event(EXPAND_ID(next->dl_server, cpu, + get_server_type(next)), + sched_switch_in_nomiss); + else { + handle_server_switch(next, cpu, DL_SERVER_FAIR); + if (IS_ENABLED(CONFIG_SCHED_CLASS_EXT)) + handle_server_switch(next, cpu, DL_SERVER_EXT); + } +} + +static void handle_sys_enter(void *data, struct pt_regs *regs, long id) +{ + struct task_struct *p; + int new_policy = -1; + pid_t pid = 0; + + new_policy = extract_params(regs, id, &pid); + if (new_policy < 0) + return; + guard(rcu)(); + p = pid ? find_task_by_vpid(pid) : current; + if (unlikely(!p) || new_policy == p->policy) + return; + + if (p->policy == SCHED_DEADLINE) + da_reset(EXPAND_ID_TASK(p)); + else if (new_policy == SCHED_DEADLINE) + da_create_or_get(EXPAND_ID_TASK(p)); +} + +static void handle_sched_wakeup(void *data, struct task_struct *tsk) +{ + if (tsk->policy == SCHED_DEADLINE) + da_handle_event(EXPAND_ID_TASK(tsk), sched_wakeup_nomiss); +} + +static int enable_nomiss(void) +{ + int retval; + + retval = da_monitor_init(); + if (retval) + return retval; + + retval = init_storage(false); + if (retval) + return retval; + rv_attach_trace_probe("nomiss", sched_dl_replenish_tp, handle_dl_replenish); + rv_attach_trace_probe("nomiss", sched_dl_throttle_tp, handle_dl_throttle); + rv_attach_trace_probe("nomiss", sched_dl_server_stop_tp, handle_dl_server_stop); + rv_attach_trace_probe("nomiss", sched_switch, handle_sched_switch); + rv_attach_trace_probe("nomiss", sched_wakeup, handle_sched_wakeup); + if (!should_skip_syscall_handle()) + rv_attach_trace_probe("nomiss", sys_enter, handle_sys_enter); + rv_attach_trace_probe("nomiss", task_newtask, handle_newtask); + rv_attach_trace_probe("nomiss", sched_process_exit, handle_exit); + + return 0; +} + +static void disable_nomiss(void) +{ + rv_this.enabled = 0; + + /* Those are RCU writers, detach earlier hoping to close a bit faster */ + rv_detach_trace_probe("nomiss", task_newtask, handle_newtask); + rv_detach_trace_probe("nomiss", sched_process_exit, handle_exit); + if (!should_skip_syscall_handle()) + rv_detach_trace_probe("nomiss", sys_enter, handle_sys_enter); + + rv_detach_trace_probe("nomiss", sched_dl_replenish_tp, handle_dl_replenish); + rv_detach_trace_probe("nomiss", sched_dl_throttle_tp, handle_dl_throttle); + rv_detach_trace_probe("nomiss", sched_dl_server_stop_tp, handle_dl_server_stop); + rv_detach_trace_probe("nomiss", sched_switch, handle_sched_switch); + rv_detach_trace_probe("nomiss", sched_wakeup, handle_sched_wakeup); + + da_monitor_destroy(); +} + +static struct rv_monitor rv_this = { + .name = "nomiss", + .description = "dl entities run to completion before their deadline.", + .enable = enable_nomiss, + .disable = disable_nomiss, + .reset = da_monitor_reset_all, + .enabled = 0, +}; + +static int __init register_nomiss(void) +{ + return rv_register_monitor(&rv_this, &rv_deadline); +} + +static void __exit unregister_nomiss(void) +{ + rv_unregister_monitor(&rv_this); +} + +module_init(register_nomiss); +module_exit(unregister_nomiss); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Gabriele Monaco "); +MODULE_DESCRIPTION("nomiss: dl entities run to completion before their deadline."); diff --git a/kernel/trace/rv/monitors/nomiss/nomiss.h b/kernel/trace/rv/monitors/nomiss/nomiss.h new file mode 100644 index 000000000000..3d1b436194d7 --- /dev/null +++ b/kernel/trace/rv/monitors/nomiss/nomiss.h @@ -0,0 +1,123 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Automatically generated C representation of nomiss automaton + * For further information about this format, see kernel documentation: + * Documentation/trace/rv/deterministic_automata.rst + */ + +#define MONITOR_NAME nomiss + +enum states_nomiss { + ready_nomiss, + idle_nomiss, + running_nomiss, + sleeping_nomiss, + throttled_nomiss, + state_max_nomiss, +}; + +#define INVALID_STATE state_max_nomiss + +enum events_nomiss { + dl_replenish_nomiss, + dl_server_idle_nomiss, + dl_server_stop_nomiss, + dl_throttle_nomiss, + sched_switch_in_nomiss, + sched_switch_suspend_nomiss, + sched_wakeup_nomiss, + event_max_nomiss, +}; + +enum envs_nomiss { + clk_nomiss, + is_constr_dl_nomiss, + is_defer_nomiss, + env_max_nomiss, + env_max_stored_nomiss = is_constr_dl_nomiss, +}; + +_Static_assert(env_max_stored_nomiss <= MAX_HA_ENV_LEN, "Not enough slots"); +#define HA_CLK_NS + +struct automaton_nomiss { + char *state_names[state_max_nomiss]; + char *event_names[event_max_nomiss]; + char *env_names[env_max_nomiss]; + unsigned char function[state_max_nomiss][event_max_nomiss]; + unsigned char initial_state; + bool final_states[state_max_nomiss]; +}; + +static const struct automaton_nomiss automaton_nomiss = { + .state_names = { + "ready", + "idle", + "running", + "sleeping", + "throttled", + }, + .event_names = { + "dl_replenish", + "dl_server_idle", + "dl_server_stop", + "dl_throttle", + "sched_switch_in", + "sched_switch_suspend", + "sched_wakeup", + }, + .env_names = { + "clk", + "is_constr_dl", + "is_defer", + }, + .function = { + { + ready_nomiss, + idle_nomiss, + sleeping_nomiss, + throttled_nomiss, + running_nomiss, + INVALID_STATE, + ready_nomiss, + }, + { + ready_nomiss, + idle_nomiss, + sleeping_nomiss, + throttled_nomiss, + running_nomiss, + INVALID_STATE, + INVALID_STATE, + }, + { + running_nomiss, + idle_nomiss, + sleeping_nomiss, + throttled_nomiss, + running_nomiss, + sleeping_nomiss, + running_nomiss, + }, + { + ready_nomiss, + sleeping_nomiss, + sleeping_nomiss, + throttled_nomiss, + running_nomiss, + INVALID_STATE, + ready_nomiss, + }, + { + ready_nomiss, + throttled_nomiss, + INVALID_STATE, + throttled_nomiss, + INVALID_STATE, + throttled_nomiss, + throttled_nomiss, + }, + }, + .initial_state = ready_nomiss, + .final_states = { 1, 0, 0, 0, 0 }, +}; diff --git a/kernel/trace/rv/monitors/nomiss/nomiss_trace.h b/kernel/trace/rv/monitors/nomiss/nomiss_trace.h new file mode 100644 index 000000000000..42e7efaca4e7 --- /dev/null +++ b/kernel/trace/rv/monitors/nomiss/nomiss_trace.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Snippet to be included in rv_trace.h + */ + +#ifdef CONFIG_RV_MON_NOMISS +DEFINE_EVENT(event_da_monitor_id, event_nomiss, + TP_PROTO(int id, char *state, char *event, char *next_state, bool final_state), + TP_ARGS(id, state, event, next_state, final_state)); + +DEFINE_EVENT(error_da_monitor_id, error_nomiss, + TP_PROTO(int id, char *state, char *event), + TP_ARGS(id, state, event)); + +DEFINE_EVENT(error_env_da_monitor_id, error_env_nomiss, + TP_PROTO(int id, char *state, char *event, char *env), + TP_ARGS(id, state, event, env)); +#endif /* CONFIG_RV_MON_NOMISS */ diff --git a/kernel/trace/rv/rv_trace.h b/kernel/trace/rv/rv_trace.h index 9e8072d863a2..9622c269789c 100644 --- a/kernel/trace/rv/rv_trace.h +++ b/kernel/trace/rv/rv_trace.h @@ -188,6 +188,7 @@ DECLARE_EVENT_CLASS(error_env_da_monitor_id, ); #include +#include // Add new monitors based on CONFIG_HA_MON_EVENTS_ID here #endif diff --git a/tools/verification/models/deadline/nomiss.dot b/tools/verification/models/deadline/nomiss.dot new file mode 100644 index 000000000000..fd1ea6bf2509 --- /dev/null +++ b/tools/verification/models/deadline/nomiss.dot @@ -0,0 +1,41 @@ +digraph state_automaton { + center = true; + size = "7,11"; + {node [shape = circle] "idle"}; + {node [shape = plaintext, style=invis, label=""] "__init_ready"}; + {node [shape = doublecircle] "ready"}; + {node [shape = circle] "ready"}; + {node [shape = circle] "running"}; + {node [shape = circle] "sleeping"}; + {node [shape = circle] "throttled"}; + "__init_ready" -> "ready"; + "idle" [label = "idle"]; + "idle" -> "idle" [ label = "dl_server_idle" ]; + "idle" -> "ready" [ label = "dl_replenish;reset(clk)" ]; + "idle" -> "running" [ label = "sched_switch_in" ]; + "idle" -> "sleeping" [ label = "dl_server_stop" ]; + "idle" -> "throttled" [ label = "dl_throttle" ]; + "ready" [label = "ready\nclk < DEADLINE_NS()", color = green3]; + "ready" -> "idle" [ label = "dl_server_idle" ]; + "ready" -> "ready" [ label = "sched_wakeup\ndl_replenish;reset(clk)" ]; + "ready" -> "running" [ label = "sched_switch_in" ]; + "ready" -> "sleeping" [ label = "dl_server_stop" ]; + "ready" -> "throttled" [ label = "dl_throttle;is_defer == 1" ]; + "running" [label = "running\nclk < DEADLINE_NS()"]; + "running" -> "idle" [ label = "dl_server_idle" ]; + "running" -> "running" [ label = "dl_replenish;reset(clk)\nsched_switch_in\nsched_wakeup" ]; + "running" -> "sleeping" [ label = "sched_switch_suspend\ndl_server_stop" ]; + "running" -> "throttled" [ label = "dl_throttle" ]; + "sleeping" [label = "sleeping"]; + "sleeping" -> "ready" [ label = "sched_wakeup\ndl_replenish;reset(clk)" ]; + "sleeping" -> "running" [ label = "sched_switch_in" ]; + "sleeping" -> "sleeping" [ label = "dl_server_stop\ndl_server_idle" ]; + "sleeping" -> "throttled" [ label = "dl_throttle;is_constr_dl == 1 || is_defer == 1" ]; + "throttled" [label = "throttled"]; + "throttled" -> "ready" [ label = "dl_replenish;reset(clk)" ]; + "throttled" -> "throttled" [ label = "sched_switch_suspend\nsched_wakeup\ndl_server_idle\ndl_throttle" ]; + { rank = min ; + "__init_ready"; + "ready"; + } +} -- 2.53.0