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kernel/tracepoint.c
19.7 KB
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/* * Copyright (C) 2008 Mathieu Desnoyers * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #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> |
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#include <linux/sched.h> |
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#include <linux/static_key.h> |
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|
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extern struct tracepoint * const __start___tracepoints_ptrs[]; extern struct tracepoint * const __stop___tracepoints_ptrs[]; |
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/* Set to 1 to enable tracepoint debug output */ static const int tracepoint_debug; /* |
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* Tracepoints mutex protects the builtin and module tracepoints and the hash * table, as well as the local module list. |
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*/ static DEFINE_MUTEX(tracepoints_mutex); |
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#ifdef CONFIG_MODULES /* Local list of struct module */ static LIST_HEAD(tracepoint_module_list); #endif /* CONFIG_MODULES */ |
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/* * Tracepoint hash table, containing the active tracepoints. * Protected by tracepoints_mutex. */ #define TRACEPOINT_HASH_BITS 6 #define TRACEPOINT_TABLE_SIZE (1 << TRACEPOINT_HASH_BITS) |
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static struct hlist_head tracepoint_table[TRACEPOINT_TABLE_SIZE]; |
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/* * Note about RCU : |
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* It is used to delay the free of multiple probes array until a quiescent |
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* state is reached. * Tracepoint entries modifications are protected by the tracepoints_mutex. */ struct tracepoint_entry { struct hlist_node hlist; |
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struct tracepoint_func *funcs; |
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int refcount; /* Number of times armed. 0 if disarmed. */ |
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char name[0]; }; |
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struct tp_probes { |
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union { struct rcu_head rcu; struct list_head list; } u; |
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struct tracepoint_func probes[0]; |
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}; |
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|
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static inline void *allocate_probes(int count) |
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{ |
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struct tp_probes *p = kmalloc(count * sizeof(struct tracepoint_func) |
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+ sizeof(struct tp_probes), GFP_KERNEL); return p == NULL ? NULL : p->probes; |
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} |
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static void rcu_free_old_probes(struct rcu_head *head) |
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{ |
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kfree(container_of(head, struct tp_probes, u.rcu)); |
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} |
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static inline void release_probes(struct tracepoint_func *old) |
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{ if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); |
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call_rcu_sched(&tp_probes->u.rcu, rcu_free_old_probes); |
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} |
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} static void debug_print_probes(struct tracepoint_entry *entry) { int i; |
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if (!tracepoint_debug || !entry->funcs) |
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return; |
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for (i = 0; entry->funcs[i].func; i++) printk(KERN_DEBUG "Probe %d : %p ", i, entry->funcs[i].func); |
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} |
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static struct tracepoint_func * tracepoint_entry_add_probe(struct tracepoint_entry *entry, void *probe, void *data) |
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{ int nr_probes = 0; |
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struct tracepoint_func *old, *new; |
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WARN_ON(!probe); debug_print_probes(entry); old = entry->funcs; if (old) { /* (N -> N+1), (N != 0, 1) probes */ |
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for (nr_probes = 0; old[nr_probes].func; nr_probes++) if (old[nr_probes].func == probe && old[nr_probes].data == data) |
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return ERR_PTR(-EEXIST); } /* + 2 : one for new probe, one for NULL func */ |
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new = allocate_probes(nr_probes + 2); |
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if (new == NULL) return ERR_PTR(-ENOMEM); if (old) |
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memcpy(new, old, nr_probes * sizeof(struct tracepoint_func)); new[nr_probes].func = probe; new[nr_probes].data = data; new[nr_probes + 1].func = NULL; |
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entry->refcount = nr_probes + 1; entry->funcs = new; debug_print_probes(entry); return old; } static void * |
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tracepoint_entry_remove_probe(struct tracepoint_entry *entry, void *probe, void *data) |
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{ int nr_probes = 0, nr_del = 0, i; |
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struct tracepoint_func *old, *new; |
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old = entry->funcs; |
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if (!old) |
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return ERR_PTR(-ENOENT); |
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|
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debug_print_probes(entry); /* (N -> M), (N > 1, M >= 0) probes */ |
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for (nr_probes = 0; old[nr_probes].func; nr_probes++) { if (!probe || (old[nr_probes].func == probe && old[nr_probes].data == data)) |
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nr_del++; } if (nr_probes - nr_del == 0) { /* N -> 0, (N > 1) */ entry->funcs = NULL; entry->refcount = 0; debug_print_probes(entry); return old; } else { int j = 0; /* N -> M, (N > 1, M > 0) */ /* + 1 for NULL */ |
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new = allocate_probes(nr_probes - nr_del + 1); |
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if (new == NULL) return ERR_PTR(-ENOMEM); |
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for (i = 0; old[i].func; i++) if (probe && (old[i].func != probe || old[i].data != data)) |
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new[j++] = old[i]; |
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new[nr_probes - nr_del].func = NULL; |
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entry->refcount = nr_probes - nr_del; entry->funcs = new; } debug_print_probes(entry); return old; } /* * Get tracepoint if the tracepoint is present in the tracepoint hash table. * Must be called with tracepoints_mutex held. * Returns NULL if not present. */ static struct tracepoint_entry *get_tracepoint(const char *name) { struct hlist_head *head; struct hlist_node *node; struct tracepoint_entry *e; u32 hash = jhash(name, strlen(name), 0); |
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head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)]; |
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hlist_for_each_entry(e, node, head, hlist) { if (!strcmp(name, e->name)) return e; } return NULL; } /* * Add the tracepoint to the tracepoint hash table. Must be called with * tracepoints_mutex held. */ static struct tracepoint_entry *add_tracepoint(const char *name) { struct hlist_head *head; struct hlist_node *node; struct tracepoint_entry *e; size_t name_len = strlen(name) + 1; u32 hash = jhash(name, name_len-1, 0); |
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head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)]; |
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hlist_for_each_entry(e, node, head, hlist) { if (!strcmp(name, e->name)) { printk(KERN_NOTICE "tracepoint %s busy ", name); return ERR_PTR(-EEXIST); /* Already there */ } } /* * Using kmalloc here to allocate a variable length element. Could * cause some memory fragmentation if overused. */ e = kmalloc(sizeof(struct tracepoint_entry) + name_len, GFP_KERNEL); if (!e) return ERR_PTR(-ENOMEM); memcpy(&e->name[0], name, name_len); e->funcs = NULL; e->refcount = 0; |
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hlist_add_head(&e->hlist, head); return e; } /* * Remove the tracepoint from the tracepoint hash table. Must be called with * mutex_lock held. */ |
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static inline void remove_tracepoint(struct tracepoint_entry *e) |
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{ |
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hlist_del(&e->hlist); |
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kfree(e); |
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} /* * Sets the probe callback corresponding to one tracepoint. */ static void set_tracepoint(struct tracepoint_entry **entry, struct tracepoint *elem, int active) { WARN_ON(strcmp((*entry)->name, elem->name) != 0); |
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if (elem->regfunc && !static_key_enabled(&elem->key) && active) |
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elem->regfunc(); |
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else if (elem->unregfunc && static_key_enabled(&elem->key) && !active) |
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elem->unregfunc(); |
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/* * rcu_assign_pointer has a smp_wmb() 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/tracepoints.h. A matching smp_read_barrier_depends() * is used. */ rcu_assign_pointer(elem->funcs, (*entry)->funcs); |
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if (active && !static_key_enabled(&elem->key)) static_key_slow_inc(&elem->key); else if (!active && static_key_enabled(&elem->key)) static_key_slow_dec(&elem->key); |
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} /* * Disable a tracepoint and its probe callback. * 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 void disable_tracepoint(struct tracepoint *elem) { |
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if (elem->unregfunc && static_key_enabled(&elem->key)) |
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elem->unregfunc(); |
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if (static_key_enabled(&elem->key)) static_key_slow_dec(&elem->key); |
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rcu_assign_pointer(elem->funcs, NULL); |
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} /** * tracepoint_update_probe_range - Update a probe range * @begin: beginning of the range * @end: end of the range * * Updates the probe callback corresponding to a range of tracepoints. |
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* Called with tracepoints_mutex held. |
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*/ |
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static void tracepoint_update_probe_range(struct tracepoint * const *begin, struct tracepoint * const *end) |
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{ |
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struct tracepoint * const *iter; |
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struct tracepoint_entry *mark_entry; |
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if (!begin) |
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return; |
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|
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for (iter = begin; iter < end; iter++) { |
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mark_entry = get_tracepoint((*iter)->name); |
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if (mark_entry) { |
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set_tracepoint(&mark_entry, *iter, |
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!!mark_entry->refcount); } else { |
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disable_tracepoint(*iter); |
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} } |
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} |
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#ifdef CONFIG_MODULES void module_update_tracepoints(void) { struct tp_module *tp_mod; list_for_each_entry(tp_mod, &tracepoint_module_list, list) tracepoint_update_probe_range(tp_mod->tracepoints_ptrs, tp_mod->tracepoints_ptrs + tp_mod->num_tracepoints); } #else /* CONFIG_MODULES */ void module_update_tracepoints(void) { } #endif /* CONFIG_MODULES */ |
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/* * Update probes, removing the faulty probes. |
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* Called with tracepoints_mutex held. |
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*/ static void tracepoint_update_probes(void) { /* Core kernel tracepoints */ |
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tracepoint_update_probe_range(__start___tracepoints_ptrs, __stop___tracepoints_ptrs); |
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/* tracepoints in modules. */ module_update_tracepoints(); } |
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static struct tracepoint_func * tracepoint_add_probe(const char *name, void *probe, void *data) |
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{ struct tracepoint_entry *entry; |
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struct tracepoint_func *old; |
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entry = get_tracepoint(name); if (!entry) { entry = add_tracepoint(name); if (IS_ERR(entry)) |
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return (struct tracepoint_func *)entry; |
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} |
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old = tracepoint_entry_add_probe(entry, probe, data); |
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if (IS_ERR(old) && !entry->refcount) remove_tracepoint(entry); return old; } |
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/** * tracepoint_probe_register - Connect a probe to a tracepoint * @name: tracepoint name * @probe: probe handler * * Returns 0 if ok, error value on error. * The probe address must at least be aligned on the architecture pointer size. */ |
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int tracepoint_probe_register(const char *name, void *probe, void *data) |
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{ |
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struct tracepoint_func *old; |
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mutex_lock(&tracepoints_mutex); |
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old = tracepoint_add_probe(name, probe, data); |
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if (IS_ERR(old)) { mutex_unlock(&tracepoints_mutex); |
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return PTR_ERR(old); |
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} |
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tracepoint_update_probes(); /* may update entry */ |
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mutex_unlock(&tracepoints_mutex); |
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release_probes(old); return 0; |
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} EXPORT_SYMBOL_GPL(tracepoint_probe_register); |
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static struct tracepoint_func * tracepoint_remove_probe(const char *name, void *probe, void *data) |
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{ struct tracepoint_entry *entry; |
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struct tracepoint_func *old; |
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entry = get_tracepoint(name); if (!entry) return ERR_PTR(-ENOENT); |
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old = tracepoint_entry_remove_probe(entry, probe, data); |
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if (IS_ERR(old)) return old; if (!entry->refcount) remove_tracepoint(entry); return old; } |
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/** * tracepoint_probe_unregister - Disconnect a probe from a tracepoint * @name: tracepoint name * @probe: probe function pointer * * We do not need to call a synchronize_sched to make sure the probes have * finished running before doing a module unload, because the module unload * itself uses stop_machine(), which insures that every preempt disabled section * have finished. */ |
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int tracepoint_probe_unregister(const char *name, void *probe, void *data) |
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{ |
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struct tracepoint_func *old; |
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mutex_lock(&tracepoints_mutex); |
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old = tracepoint_remove_probe(name, probe, data); |
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if (IS_ERR(old)) { mutex_unlock(&tracepoints_mutex); |
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return PTR_ERR(old); |
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} |
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tracepoint_update_probes(); /* may update entry */ |
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mutex_unlock(&tracepoints_mutex); |
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release_probes(old); return 0; |
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} EXPORT_SYMBOL_GPL(tracepoint_probe_unregister); |
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static LIST_HEAD(old_probes); static int need_update; static void tracepoint_add_old_probes(void *old) { need_update = 1; if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); list_add(&tp_probes->u.list, &old_probes); } } /** * tracepoint_probe_register_noupdate - register a probe but not connect * @name: tracepoint name * @probe: probe handler * * caller must call tracepoint_probe_update_all() */ |
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int tracepoint_probe_register_noupdate(const char *name, void *probe, void *data) |
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{ |
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struct tracepoint_func *old; |
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mutex_lock(&tracepoints_mutex); |
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old = tracepoint_add_probe(name, probe, data); |
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if (IS_ERR(old)) { mutex_unlock(&tracepoints_mutex); return PTR_ERR(old); } tracepoint_add_old_probes(old); mutex_unlock(&tracepoints_mutex); return 0; } EXPORT_SYMBOL_GPL(tracepoint_probe_register_noupdate); /** * tracepoint_probe_unregister_noupdate - remove a probe but not disconnect * @name: tracepoint name * @probe: probe function pointer * * caller must call tracepoint_probe_update_all() */ |
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int tracepoint_probe_unregister_noupdate(const char *name, void *probe, void *data) |
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{ |
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struct tracepoint_func *old; |
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mutex_lock(&tracepoints_mutex); |
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old = tracepoint_remove_probe(name, probe, data); |
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if (IS_ERR(old)) { mutex_unlock(&tracepoints_mutex); return PTR_ERR(old); } tracepoint_add_old_probes(old); mutex_unlock(&tracepoints_mutex); return 0; } EXPORT_SYMBOL_GPL(tracepoint_probe_unregister_noupdate); /** * tracepoint_probe_update_all - update tracepoints */ void tracepoint_probe_update_all(void) { LIST_HEAD(release_probes); struct tp_probes *pos, *next; mutex_lock(&tracepoints_mutex); if (!need_update) { mutex_unlock(&tracepoints_mutex); return; } if (!list_empty(&old_probes)) list_replace_init(&old_probes, &release_probes); need_update = 0; |
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tracepoint_update_probes(); |
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mutex_unlock(&tracepoints_mutex); |
127cafbb2 tracepoint: intro... |
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list_for_each_entry_safe(pos, next, &release_probes, u.list) { list_del(&pos->u.list); call_rcu_sched(&pos->u.rcu, rcu_free_old_probes); } } EXPORT_SYMBOL_GPL(tracepoint_probe_update_all); |
97e1c18e8 tracing: Kernel T... |
502 503 504 505 506 507 508 509 510 511 |
/** * tracepoint_get_iter_range - Get a next tracepoint iterator given a range. * @tracepoint: current tracepoints (in), next tracepoint (out) * @begin: beginning of the range * @end: end of the range * * Returns whether a next tracepoint has been found (1) or not (0). * Will return the first tracepoint in the range if the input tracepoint is * NULL. */ |
b75ef8b44 Tracepoint: Disso... |
512 |
static int tracepoint_get_iter_range(struct tracepoint * const **tracepoint, |
654986462 tracepoints: Fix ... |
513 |
struct tracepoint * const *begin, struct tracepoint * const *end) |
97e1c18e8 tracing: Kernel T... |
514 515 516 517 518 519 520 521 522 |
{ if (!*tracepoint && begin != end) { *tracepoint = begin; return 1; } if (*tracepoint >= begin && *tracepoint < end) return 1; return 0; } |
97e1c18e8 tracing: Kernel T... |
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|
b75ef8b44 Tracepoint: Disso... |
524 |
#ifdef CONFIG_MODULES |
97e1c18e8 tracing: Kernel T... |
525 526 527 |
static void tracepoint_get_iter(struct tracepoint_iter *iter) { int found = 0; |
b75ef8b44 Tracepoint: Disso... |
528 |
struct tp_module *iter_mod; |
97e1c18e8 tracing: Kernel T... |
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/* Core kernel tracepoints */ if (!iter->module) { found = tracepoint_get_iter_range(&iter->tracepoint, |
654986462 tracepoints: Fix ... |
533 534 |
__start___tracepoints_ptrs, __stop___tracepoints_ptrs); |
97e1c18e8 tracing: Kernel T... |
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if (found) goto end; } |
b75ef8b44 Tracepoint: Disso... |
538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 |
/* Tracepoints in modules */ mutex_lock(&tracepoints_mutex); list_for_each_entry(iter_mod, &tracepoint_module_list, list) { /* * Sorted module list */ if (iter_mod < iter->module) continue; else if (iter_mod > iter->module) iter->tracepoint = NULL; found = tracepoint_get_iter_range(&iter->tracepoint, iter_mod->tracepoints_ptrs, iter_mod->tracepoints_ptrs + iter_mod->num_tracepoints); if (found) { iter->module = iter_mod; break; } } mutex_unlock(&tracepoints_mutex); |
97e1c18e8 tracing: Kernel T... |
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end: if (!found) tracepoint_iter_reset(iter); } |
b75ef8b44 Tracepoint: Disso... |
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#else /* CONFIG_MODULES */ static void tracepoint_get_iter(struct tracepoint_iter *iter) { int found = 0; /* Core kernel tracepoints */ found = tracepoint_get_iter_range(&iter->tracepoint, __start___tracepoints_ptrs, __stop___tracepoints_ptrs); if (!found) tracepoint_iter_reset(iter); } #endif /* CONFIG_MODULES */ |
97e1c18e8 tracing: Kernel T... |
575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 |
void tracepoint_iter_start(struct tracepoint_iter *iter) { tracepoint_get_iter(iter); } EXPORT_SYMBOL_GPL(tracepoint_iter_start); void tracepoint_iter_next(struct tracepoint_iter *iter) { iter->tracepoint++; /* * iter->tracepoint may be invalid because we blindly incremented it. * Make sure it is valid by marshalling on the tracepoints, getting the * tracepoints from following modules if necessary. */ tracepoint_get_iter(iter); } EXPORT_SYMBOL_GPL(tracepoint_iter_next); void tracepoint_iter_stop(struct tracepoint_iter *iter) { } EXPORT_SYMBOL_GPL(tracepoint_iter_stop); void tracepoint_iter_reset(struct tracepoint_iter *iter) { |
b75ef8b44 Tracepoint: Disso... |
601 |
#ifdef CONFIG_MODULES |
97e1c18e8 tracing: Kernel T... |
602 |
iter->module = NULL; |
b75ef8b44 Tracepoint: Disso... |
603 |
#endif /* CONFIG_MODULES */ |
97e1c18e8 tracing: Kernel T... |
604 605 606 |
iter->tracepoint = NULL; } EXPORT_SYMBOL_GPL(tracepoint_iter_reset); |
32f857427 tracepoints: use ... |
607 |
|
227a83756 markers/tracpoint... |
608 |
#ifdef CONFIG_MODULES |
b75ef8b44 Tracepoint: Disso... |
609 610 611 612 613 614 |
static int tracepoint_module_coming(struct module *mod) { struct tp_module *tp_mod, *iter; int ret = 0; /* |
c10076c43 tracepoints/modul... |
615 616 617 |
* We skip modules that taint the kernel, especially those with different * module headers (for forced load), to make sure we don't cause a crash. * Staging and out-of-tree GPL modules are fine. |
b75ef8b44 Tracepoint: Disso... |
618 |
*/ |
c10076c43 tracepoints/modul... |
619 |
if (mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP))) |
b75ef8b44 Tracepoint: Disso... |
620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 |
return 0; mutex_lock(&tracepoints_mutex); tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL); if (!tp_mod) { ret = -ENOMEM; goto end; } tp_mod->num_tracepoints = mod->num_tracepoints; tp_mod->tracepoints_ptrs = mod->tracepoints_ptrs; /* * tracepoint_module_list is kept sorted by struct module pointer * address for iteration on tracepoints from a seq_file that can release * the mutex between calls. */ list_for_each_entry_reverse(iter, &tracepoint_module_list, list) { BUG_ON(iter == tp_mod); /* Should never be in the list twice */ if (iter < tp_mod) { /* We belong to the location right after iter. */ list_add(&tp_mod->list, &iter->list); goto module_added; } } /* We belong to the beginning of the list */ list_add(&tp_mod->list, &tracepoint_module_list); module_added: tracepoint_update_probe_range(mod->tracepoints_ptrs, mod->tracepoints_ptrs + mod->num_tracepoints); end: mutex_unlock(&tracepoints_mutex); return ret; } static int tracepoint_module_going(struct module *mod) { struct tp_module *pos; mutex_lock(&tracepoints_mutex); tracepoint_update_probe_range(mod->tracepoints_ptrs, mod->tracepoints_ptrs + mod->num_tracepoints); list_for_each_entry(pos, &tracepoint_module_list, list) { if (pos->tracepoints_ptrs == mod->tracepoints_ptrs) { list_del(&pos->list); kfree(pos); break; } } /* * In the case of modules that were tainted at "coming", we'll simply * walk through the list without finding it. We cannot use the "tainted" * flag on "going", in case a module taints the kernel only after being * loaded. */ mutex_unlock(&tracepoints_mutex); return 0; } |
227a83756 markers/tracpoint... |
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|
32f857427 tracepoints: use ... |
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int tracepoint_module_notify(struct notifier_block *self, unsigned long val, void *data) { struct module *mod = data; |
b75ef8b44 Tracepoint: Disso... |
681 |
int ret = 0; |
32f857427 tracepoints: use ... |
682 683 684 |
switch (val) { case MODULE_STATE_COMING: |
b75ef8b44 Tracepoint: Disso... |
685 686 687 688 |
ret = tracepoint_module_coming(mod); break; case MODULE_STATE_LIVE: break; |
32f857427 tracepoints: use ... |
689 |
case MODULE_STATE_GOING: |
b75ef8b44 Tracepoint: Disso... |
690 |
ret = tracepoint_module_going(mod); |
32f857427 tracepoints: use ... |
691 692 |
break; } |
b75ef8b44 Tracepoint: Disso... |
693 |
return ret; |
32f857427 tracepoints: use ... |
694 695 696 697 698 699 700 701 702 703 704 705 |
} struct notifier_block tracepoint_module_nb = { .notifier_call = tracepoint_module_notify, .priority = 0, }; static int init_tracepoints(void) { return register_module_notifier(&tracepoint_module_nb); } __initcall(init_tracepoints); |
227a83756 markers/tracpoint... |
706 |
#endif /* CONFIG_MODULES */ |
a871bd33a tracing: Add sysc... |
707 |
|
3d27d8cb3 tracing: Make sys... |
708 |
#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS |
60d970c25 tracing: Fix sysc... |
709 |
|
974198758 tracing: Move tra... |
710 |
/* NB: reg/unreg are called while guarded with the tracepoints_mutex */ |
a871bd33a tracing: Add sysc... |
711 712 713 714 715 716 |
static int sys_tracepoint_refcount; void syscall_regfunc(void) { unsigned long flags; struct task_struct *g, *t; |
a871bd33a tracing: Add sysc... |
717 718 719 |
if (!sys_tracepoint_refcount) { read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, t) { |
cc3b13c11 tracing: Don't tr... |
720 721 722 |
/* Skip kernel threads. */ if (t->mm) set_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); |
a871bd33a tracing: Add sysc... |
723 724 725 726 |
} while_each_thread(g, t); read_unlock_irqrestore(&tasklist_lock, flags); } sys_tracepoint_refcount++; |
a871bd33a tracing: Add sysc... |
727 728 729 730 731 732 |
} void syscall_unregfunc(void) { unsigned long flags; struct task_struct *g, *t; |
a871bd33a tracing: Add sysc... |
733 734 735 736 |
sys_tracepoint_refcount--; if (!sys_tracepoint_refcount) { read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, t) { |
667000011 tracing: Rename F... |
737 |
clear_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); |
a871bd33a tracing: Add sysc... |
738 739 740 |
} while_each_thread(g, t); read_unlock_irqrestore(&tasklist_lock, flags); } |
a871bd33a tracing: Add sysc... |
741 |
} |
60d970c25 tracing: Fix sysc... |
742 |
#endif |