// SPDX-License-Identifier: GPL-2.0-or-later/* * Copyright (C) 2008-2014 Mathieu Desnoyers */#include <linux/module.h>#include <linux/mutex.h>#include <linux/types.h>#include <linux/jhash.h>#include <linux/list.h>#include <linux/rcupdate.h>#include <linux/tracepoint.h>#include <linux/err.h>#include <linux/slab.h>#include <linux/sched/signal.h>#include <linux/sched/task.h>#include <linux/static_key.h> extern tracepoint_ptr_t __start___tracepoints_ptrs[];extern tracepoint_ptr_t __stop___tracepoints_ptrs[]; DEFINE_SRCU(tracepoint_srcu);EXPORT_SYMBOL_GPL(tracepoint_srcu); /* Set to 1 to enable tracepoint debug output */static const int tracepoint_debug; #ifdef CONFIG_MODULES/* * Tracepoint module list mutex protects the local module list. */static DEFINE_MUTEX(tracepoint_module_list_mutex); /* Local list of struct tp_module */static LIST_HEAD(tracepoint_module_list);#endif /* CONFIG_MODULES */ /* * tracepoints_mutex protects the builtin and module tracepoints. * tracepoints_mutex nests inside tracepoint_module_list_mutex. */static DEFINE_MUTEX(tracepoints_mutex); static struct rcu_head *early_probes;static bool ok_to_free_tracepoints; /* * Note about RCU : * It is used to delay the free of multiple probes array until a quiescent * state is reached. */struct tp_probes { struct rcu_head rcu; struct tracepoint_func probes[];}; /* Called in removal of a func but failed to allocate a new tp_funcs */static void tp_stub_func(void){ return;} static inline void *allocate_probes(int count){ struct tp_probes *p = kmalloc(struct_size(p, probes, count), GFP_KERNEL); return p == NULL ? NULL : p->probes;} static void srcu_free_old_probes(struct rcu_head *head){ kfree(container_of(head, struct tp_probes, rcu));} static void rcu_free_old_probes(struct rcu_head *head){ call_srcu(&tracepoint_srcu, head, srcu_free_old_probes);} static __init int release_early_probes(void){ struct rcu_head *tmp; ok_to_free_tracepoints = true; while (early_probes) { tmp = early_probes; early_probes = tmp->next; call_rcu(tmp, rcu_free_old_probes); } return 0;} /* SRCU is initialized at core_initcall */postcore_initcall(release_early_probes); static inline void release_probes(struct tracepoint_func *old){ if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); /* * We can't free probes if SRCU is not initialized yet. * Postpone the freeing till after SRCU is initialized. */ if (unlikely(!ok_to_free_tracepoints)) { tp_probes->rcu.next = early_probes; early_probes = &tp_probes->rcu; return; } /* * Tracepoint probes are protected by both sched RCU and SRCU, * by calling the SRCU callback in the sched RCU callback we * cover both cases. So let us chain the SRCU and sched RCU * callbacks to wait for both grace periods. */ call_rcu(&tp_probes->rcu, rcu_free_old_probes); }} static void debug_print_probes(struct tracepoint_func *funcs){ int i; if (!tracepoint_debug || !funcs) return; for (i = 0; funcs[i].func; i++) printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func);} static struct tracepoint_func *func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func, int prio){ struct tracepoint_func *old, *new; int iter_probes; /* Iterate over old probe array. */ int nr_probes = 0; /* Counter for probes */ int pos = -1; /* Insertion position into new array */ if (WARN_ON(!tp_func->func)) return ERR_PTR(-EINVAL); debug_print_probes(*funcs); old = *funcs; if (old) { /* (N -> N+1), (N != 0, 1) probes */ for (iter_probes = 0; old[iter_probes].func; iter_probes++) { if (old[iter_probes].func == tp_stub_func) continue; /* Skip stub functions. */ if (old[iter_probes].func == tp_func->func && old[iter_probes].data == tp_func->data) return ERR_PTR(-EEXIST); nr_probes++; } } /* + 2 : one for new probe, one for NULL func */ new = allocate_probes(nr_probes + 2); if (new == NULL) return ERR_PTR(-ENOMEM); if (old) { nr_probes = 0; for (iter_probes = 0; old[iter_probes].func; iter_probes++) { if (old[iter_probes].func == tp_stub_func) continue; /* Insert before probes of lower priority */ if (pos < 0 && old[iter_probes].prio < prio) pos = nr_probes++; new[nr_probes++] = old[iter_probes]; } if (pos < 0) pos = nr_probes++; /* nr_probes now points to the end of the new array */ } else { pos = 0; nr_probes = 1; /* must point at end of array */ } new[pos] = *tp_func; new[nr_probes].func = NULL; *funcs = new; debug_print_probes(*funcs); return old;} static void *func_remove(struct tracepoint_func **funcs, struct tracepoint_func *tp_func){ int nr_probes = 0, nr_del = 0, i; struct tracepoint_func *old, *new; old = *funcs; if (!old) return ERR_PTR(-ENOENT); debug_print_probes(*funcs); /* (N -> M), (N > 1, M >= 0) probes */ if (tp_func->func) { for (nr_probes = 0; old[nr_probes].func; nr_probes++) { if ((old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) || old[nr_probes].func == tp_stub_func) nr_del++; } } /* * If probe is NULL, then nr_probes = nr_del = 0, and then the * entire entry will be removed. */ if (nr_probes - nr_del == 0) { /* N -> 0, (N > 1) */ *funcs = NULL; debug_print_probes(*funcs); return old; } else { int j = 0; /* N -> M, (N > 1, M > 0) */ /* + 1 for NULL */ new = allocate_probes(nr_probes - nr_del + 1); if (new) { for (i = 0; old[i].func; i++) { if ((old[i].func != tp_func->func || old[i].data != tp_func->data) && old[i].func != tp_stub_func) new[j++] = old[i]; } new[nr_probes - nr_del].func = NULL; *funcs = new; } else { /* * Failed to allocate, replace the old function * with calls to tp_stub_func. */ for (i = 0; old[i].func; i++) { if (old[i].func == tp_func->func && old[i].data == tp_func->data) WRITE_ONCE(old[i].func, tp_stub_func); } *funcs = old; } } debug_print_probes(*funcs); return old;} static void tracepoint_update_call(struct tracepoint *tp, struct tracepoint_func *tp_funcs, bool sync){ void *func = tp->iterator; /* Synthetic events do not have static call sites */ if (!tp->static_call_key) return; if (!tp_funcs[1].func) { func = tp_funcs[0].func; /* * If going from the iterator back to a single caller, * we need to synchronize with __DO_TRACE to make sure * that the data passed to the callback is the one that * belongs to that callback. */ if (sync) tracepoint_synchronize_unregister(); } __static_call_update(tp->static_call_key, tp->static_call_tramp, func);} /* * Add the probe function to a tracepoint. */static int tracepoint_add_func(struct tracepoint *tp, struct tracepoint_func *func, int prio){ struct tracepoint_func *old, *tp_funcs; int ret; if (tp->regfunc && !static_key_enabled(&tp->key)) { ret = tp->regfunc(); if (ret < 0) return ret; } tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_add(&tp_funcs, func, prio); if (IS_ERR(old)) { WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); return PTR_ERR(old); } /* * rcu_assign_pointer has as smp_store_release() which makes sure * that the new probe callbacks array is consistent before setting * a pointer to it. This array is referenced by __DO_TRACE from * include/linux/tracepoint.h using rcu_dereference_sched(). */ rcu_assign_pointer(tp->funcs, tp_funcs); tracepoint_update_call(tp, tp_funcs, false); static_key_enable(&tp->key); release_probes(old); return 0;} /* * Remove a probe function from a tracepoint. * Note: only waiting an RCU period after setting elem->call to the empty * function insures that the original callback is not used anymore. This insured * by preempt_disable around the call site. */static int tracepoint_remove_func(struct tracepoint *tp, struct tracepoint_func *func){ struct tracepoint_func *old, *tp_funcs; tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_remove(&tp_funcs, func); if (WARN_ON_ONCE(IS_ERR(old))) return PTR_ERR(old); if (tp_funcs == old) /* Failed allocating new tp_funcs, replaced func with stub */ return 0; if (!tp_funcs) { /* Removed last function */ if (tp->unregfunc && static_key_enabled(&tp->key)) tp->unregfunc(); static_key_disable(&tp->key); rcu_assign_pointer(tp->funcs, tp_funcs); } else { rcu_assign_pointer(tp->funcs, tp_funcs); tracepoint_update_call(tp, tp_funcs, tp_funcs[0].func != old[0].func); } release_probes(old); return 0;} /** * tracepoint_probe_register_prio - Connect a probe to a tracepoint with priority * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * @prio: priority of this function over other registered functions * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data, int prio){ struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; tp_func.prio = prio; ret = tracepoint_add_func(tp, &tp_func, prio); mutex_unlock(&tracepoints_mutex); return ret;}EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio); /** * tracepoint_probe_register - Connect a probe to a tracepoint * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data){ return tracepoint_probe_register_prio(tp, probe, data, TRACEPOINT_DEFAULT_PRIO);}EXPORT_SYMBOL_GPL(tracepoint_probe_register); /** * tracepoint_probe_unregister - Disconnect a probe from a tracepoint * @tp: tracepoint * @probe: probe function pointer * @data: tracepoint data * * Returns 0 if ok, error value on error. */int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data){ struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; ret = tracepoint_remove_func(tp, &tp_func); mutex_unlock(&tracepoints_mutex); return ret;}EXPORT_SYMBOL_GPL(tracepoint_probe_unregister); static void for_each_tracepoint_range( tracepoint_ptr_t *begin, tracepoint_ptr_t *end, void (*fct)(struct tracepoint *tp, void *priv), void *priv){ tracepoint_ptr_t *iter; if (!begin) return; for (iter = begin; iter < end; iter++) fct(tracepoint_ptr_deref(iter), priv);} #ifdef CONFIG_MODULESbool trace_module_has_bad_taint(struct module *mod){ return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) | (1 << TAINT_UNSIGNED_MODULE));} static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list); /** * register_tracepoint_notifier - register tracepoint coming/going notifier * @nb: notifier block * * Notifiers registered with this function are called on module * coming/going with the tracepoint_module_list_mutex held. * The notifier block callback should expect a "struct tp_module" data * pointer. */int register_tracepoint_module_notifier(struct notifier_block *nb){ struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_register(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_COMING, tp_mod);end: mutex_unlock(&tracepoint_module_list_mutex); return ret;}EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier); /** * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier * @nb: notifier block * * The notifier block callback should expect a "struct tp_module" data * pointer. */int unregister_tracepoint_module_notifier(struct notifier_block *nb){ struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_unregister(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_GOING, tp_mod);end: mutex_unlock(&tracepoint_module_list_mutex); return ret; }EXPORT_SYMBOL_GPL(unregister_tracepoint_module_notifier); /* * Ensure the tracer unregistered the module's probes before the module * teardown is performed. Prevents leaks of probe and data pointers. */static void tp_module_going_check_quiescent(struct tracepoint *tp, void *priv){ WARN_ON_ONCE(tp->funcs);} static int tracepoint_module_coming(struct module *mod){ struct tp_module *tp_mod; int ret = 0;Lines 1–500 of 646. Load more
// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2008-2014 Mathieu Desnoyers */ #include <linux/module.h> #include <linux/mutex.h> #include <linux/types.h> #include <linux/jhash.h> #include <linux/list.h> #include <linux/rcupdate.h> #include <linux/tracepoint.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/sched/signal.h> #include <linux/sched/task.h> #include <linux/static_key.h> extern tracepoint_ptr_t __start___tracepoints_ptrs[]; extern tracepoint_ptr_t __stop___tracepoints_ptrs[]; DEFINE_SRCU(tracepoint_srcu); EXPORT_SYMBOL_GPL(tracepoint_srcu); /* Set to 1 to enable tracepoint debug output */ static const int tracepoint_debug; #ifdef CONFIG_MODULES /* * Tracepoint module list mutex protects the local module list. */ static DEFINE_MUTEX(tracepoint_module_list_mutex); /* Local list of struct tp_module */ static LIST_HEAD(tracepoint_module_list); #endif /* CONFIG_MODULES */ /* * tracepoints_mutex protects the builtin and module tracepoints. * tracepoints_mutex nests inside tracepoint_module_list_mutex. */ static DEFINE_MUTEX(tracepoints_mutex); static struct rcu_head *early_probes; static bool ok_to_free_tracepoints; /* * Note about RCU : * It is used to delay the free of multiple probes array until a quiescent * state is reached. */ struct tp_probes { struct rcu_head rcu; struct tracepoint_func probes[]; }; /* Called in removal of a func but failed to allocate a new tp_funcs */ static void tp_stub_func(void) { return; } static inline void *allocate_probes(int count) { struct tp_probes *p = kmalloc(struct_size(p, probes, count), GFP_KERNEL); return p == NULL ? NULL : p->probes; } static void srcu_free_old_probes(struct rcu_head *head) { kfree(container_of(head, struct tp_probes, rcu)); } static void rcu_free_old_probes(struct rcu_head *head) { call_srcu(&tracepoint_srcu, head, srcu_free_old_probes); } static __init int release_early_probes(void) { struct rcu_head *tmp; ok_to_free_tracepoints = true; while (early_probes) { tmp = early_probes; early_probes = tmp->next; call_rcu(tmp, rcu_free_old_probes); } return 0; } /* SRCU is initialized at core_initcall */ postcore_initcall(release_early_probes); static inline void release_probes(struct tracepoint_func *old) { if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); /* * We can't free probes if SRCU is not initialized yet. * Postpone the freeing till after SRCU is initialized. */ if (unlikely(!ok_to_free_tracepoints)) { tp_probes->rcu.next = early_probes; early_probes = &tp_probes->rcu; return; } /* * Tracepoint probes are protected by both sched RCU and SRCU, * by calling the SRCU callback in the sched RCU callback we * cover both cases. So let us chain the SRCU and sched RCU * callbacks to wait for both grace periods. */ call_rcu(&tp_probes->rcu, rcu_free_old_probes); } } static void debug_print_probes(struct tracepoint_func *funcs) { int i; if (!tracepoint_debug || !funcs) return; for (i = 0; funcs[i].func; i++) printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func); } static struct tracepoint_func * func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func, int prio) { struct tracepoint_func *old, *new; int iter_probes; /* Iterate over old probe array. */ int nr_probes = 0; /* Counter for probes */ int pos = -1; /* Insertion position into new array */ if (WARN_ON(!tp_func->func)) return ERR_PTR(-EINVAL); debug_print_probes(*funcs); old = *funcs; if (old) { /* (N -> N+1), (N != 0, 1) probes */ for (iter_probes = 0; old[iter_probes].func; iter_probes++) { if (old[iter_probes].func == tp_stub_func) continue; /* Skip stub functions. */ if (old[iter_probes].func == tp_func->func && old[iter_probes].data == tp_func->data) return ERR_PTR(-EEXIST); nr_probes++; } } /* + 2 : one for new probe, one for NULL func */ new = allocate_probes(nr_probes + 2); if (new == NULL) return ERR_PTR(-ENOMEM); if (old) { nr_probes = 0; for (iter_probes = 0; old[iter_probes].func; iter_probes++) { if (old[iter_probes].func == tp_stub_func) continue; /* Insert before probes of lower priority */ if (pos < 0 && old[iter_probes].prio < prio) pos = nr_probes++; new[nr_probes++] = old[iter_probes]; } if (pos < 0) pos = nr_probes++; /* nr_probes now points to the end of the new array */ } else { pos = 0; nr_probes = 1; /* must point at end of array */ } new[pos] = *tp_func; new[nr_probes].func = NULL; *funcs = new; debug_print_probes(*funcs); return old; } static void *func_remove(struct tracepoint_func **funcs, struct tracepoint_func *tp_func) { int nr_probes = 0, nr_del = 0, i; struct tracepoint_func *old, *new; old = *funcs; if (!old) return ERR_PTR(-ENOENT); debug_print_probes(*funcs); /* (N -> M), (N > 1, M >= 0) probes */ if (tp_func->func) { for (nr_probes = 0; old[nr_probes].func; nr_probes++) { if ((old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) || old[nr_probes].func == tp_stub_func) nr_del++; } } /* * If probe is NULL, then nr_probes = nr_del = 0, and then the * entire entry will be removed. */ if (nr_probes - nr_del == 0) { /* N -> 0, (N > 1) */ *funcs = NULL; debug_print_probes(*funcs); return old; } else { int j = 0; /* N -> M, (N > 1, M > 0) */ /* + 1 for NULL */ new = allocate_probes(nr_probes - nr_del + 1); if (new) { for (i = 0; old[i].func; i++) { if ((old[i].func != tp_func->func || old[i].data != tp_func->data) && old[i].func != tp_stub_func) new[j++] = old[i]; } new[nr_probes - nr_del].func = NULL; *funcs = new; } else { /* * Failed to allocate, replace the old function * with calls to tp_stub_func. */ for (i = 0; old[i].func; i++) { if (old[i].func == tp_func->func && old[i].data == tp_func->data) WRITE_ONCE(old[i].func, tp_stub_func); } *funcs = old; } } debug_print_probes(*funcs); return old; } static void tracepoint_update_call(struct tracepoint *tp, struct tracepoint_func *tp_funcs, bool sync) { void *func = tp->iterator; /* Synthetic events do not have static call sites */ if (!tp->static_call_key) return; if (!tp_funcs[1].func) { func = tp_funcs[0].func; /* * If going from the iterator back to a single caller, * we need to synchronize with __DO_TRACE to make sure * that the data passed to the callback is the one that * belongs to that callback. */ if (sync) tracepoint_synchronize_unregister(); } __static_call_update(tp->static_call_key, tp->static_call_tramp, func); } /* * Add the probe function to a tracepoint. */ static int tracepoint_add_func(struct tracepoint *tp, struct tracepoint_func *func, int prio) { struct tracepoint_func *old, *tp_funcs; int ret; if (tp->regfunc && !static_key_enabled(&tp->key)) { ret = tp->regfunc(); if (ret < 0) return ret; } tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_add(&tp_funcs, func, prio); if (IS_ERR(old)) { WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); return PTR_ERR(old); } /* * rcu_assign_pointer has as smp_store_release() which makes sure * that the new probe callbacks array is consistent before setting * a pointer to it. This array is referenced by __DO_TRACE from * include/linux/tracepoint.h using rcu_dereference_sched(). */ rcu_assign_pointer(tp->funcs, tp_funcs); tracepoint_update_call(tp, tp_funcs, false); static_key_enable(&tp->key); release_probes(old); return 0; } /* * Remove a probe function from a tracepoint. * Note: only waiting an RCU period after setting elem->call to the empty * function insures that the original callback is not used anymore. This insured * by preempt_disable around the call site. */ static int tracepoint_remove_func(struct tracepoint *tp, struct tracepoint_func *func) { struct tracepoint_func *old, *tp_funcs; tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_remove(&tp_funcs, func); if (WARN_ON_ONCE(IS_ERR(old))) return PTR_ERR(old); if (tp_funcs == old) /* Failed allocating new tp_funcs, replaced func with stub */ return 0; if (!tp_funcs) { /* Removed last function */ if (tp->unregfunc && static_key_enabled(&tp->key)) tp->unregfunc(); static_key_disable(&tp->key); rcu_assign_pointer(tp->funcs, tp_funcs); } else { rcu_assign_pointer(tp->funcs, tp_funcs); tracepoint_update_call(tp, tp_funcs, tp_funcs[0].func != old[0].func); } release_probes(old); return 0; } /** * tracepoint_probe_register_prio - Connect a probe to a tracepoint with priority * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * @prio: priority of this function over other registered functions * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */ int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data, int prio) { struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; tp_func.prio = prio; ret = tracepoint_add_func(tp, &tp_func, prio); mutex_unlock(&tracepoints_mutex); return ret; } EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio); /** * tracepoint_probe_register - Connect a probe to a tracepoint * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */ int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) { return tracepoint_probe_register_prio(tp, probe, data, TRACEPOINT_DEFAULT_PRIO); } EXPORT_SYMBOL_GPL(tracepoint_probe_register); /** * tracepoint_probe_unregister - Disconnect a probe from a tracepoint * @tp: tracepoint * @probe: probe function pointer * @data: tracepoint data * * Returns 0 if ok, error value on error. */ int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data) { struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; ret = tracepoint_remove_func(tp, &tp_func); mutex_unlock(&tracepoints_mutex); return ret; } EXPORT_SYMBOL_GPL(tracepoint_probe_unregister); static void for_each_tracepoint_range( tracepoint_ptr_t *begin, tracepoint_ptr_t *end, void (*fct)(struct tracepoint *tp, void *priv), void *priv) { tracepoint_ptr_t *iter; if (!begin) return; for (iter = begin; iter < end; iter++) fct(tracepoint_ptr_deref(iter), priv); } #ifdef CONFIG_MODULES bool trace_module_has_bad_taint(struct module *mod) { return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) | (1 << TAINT_UNSIGNED_MODULE)); } static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list); /** * register_tracepoint_notifier - register tracepoint coming/going notifier * @nb: notifier block * * Notifiers registered with this function are called on module * coming/going with the tracepoint_module_list_mutex held. * The notifier block callback should expect a "struct tp_module" data * pointer. */ int register_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_register(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_COMING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier); /** * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier * @nb: notifier block * * The notifier block callback should expect a "struct tp_module" data * pointer. */ int unregister_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_unregister(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_GOING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(unregister_tracepoint_module_notifier); /* * Ensure the tracer unregistered the module's probes before the module * teardown is performed. Prevents leaks of probe and data pointers. */ static void tp_module_going_check_quiescent(struct tracepoint *tp, void *priv) { WARN_ON_ONCE(tp->funcs); } static int tracepoint_module_coming(struct module *mod) { struct tp_module *tp_mod; int ret = 0;