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@@ -1,5 +1,5 @@
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/*
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- * Copyright (C) 2008 Mathieu Desnoyers
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+ * Copyright (C) 2008-2014 Mathieu Desnoyers
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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@@ -33,39 +33,27 @@ extern struct tracepoint * const __stop___tracepoints_ptrs[];
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/* Set to 1 to enable tracepoint debug output */
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static const int tracepoint_debug;
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+#ifdef CONFIG_MODULES
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/*
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- * Tracepoints mutex protects the builtin and module tracepoints and the hash
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- * table, as well as the local module list.
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+ * Tracepoint module list mutex protects the local module list.
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*/
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-static DEFINE_MUTEX(tracepoints_mutex);
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+static DEFINE_MUTEX(tracepoint_module_list_mutex);
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-#ifdef CONFIG_MODULES
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-/* Local list of struct module */
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+/* Local list of struct tp_module */
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static LIST_HEAD(tracepoint_module_list);
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#endif /* CONFIG_MODULES */
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/*
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- * Tracepoint hash table, containing the active tracepoints.
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- * Protected by tracepoints_mutex.
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+ * tracepoints_mutex protects the builtin and module tracepoints.
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+ * tracepoints_mutex nests inside tracepoint_module_list_mutex.
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*/
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-#define TRACEPOINT_HASH_BITS 6
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-#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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+static DEFINE_MUTEX(tracepoints_mutex);
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/*
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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.
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- * Tracepoint entries modifications are protected by the tracepoints_mutex.
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*/
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-struct tracepoint_entry {
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- 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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- int enabled; /* Tracepoint enabled */
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- char name[0];
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-};
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-
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struct tp_probes {
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struct rcu_head rcu;
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struct tracepoint_func probes[0];
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@@ -92,34 +80,33 @@ static inline void release_probes(struct tracepoint_func *old)
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}
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}
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-static void debug_print_probes(struct tracepoint_entry *entry)
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+static void debug_print_probes(struct tracepoint_func *funcs)
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{
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int i;
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- if (!tracepoint_debug || !entry->funcs)
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+ if (!tracepoint_debug || !funcs)
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return;
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- for (i = 0; entry->funcs[i].func; i++)
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- printk(KERN_DEBUG "Probe %d : %p\n", i, entry->funcs[i].func);
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+ for (i = 0; funcs[i].func; i++)
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+ printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func);
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}
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-static struct tracepoint_func *
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-tracepoint_entry_add_probe(struct tracepoint_entry *entry,
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- void *probe, void *data)
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+static struct tracepoint_func *func_add(struct tracepoint_func **funcs,
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+ struct tracepoint_func *tp_func)
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{
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int nr_probes = 0;
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struct tracepoint_func *old, *new;
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- if (WARN_ON(!probe))
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+ if (WARN_ON(!tp_func->func))
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return ERR_PTR(-EINVAL);
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- debug_print_probes(entry);
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- old = entry->funcs;
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+ debug_print_probes(*funcs);
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+ old = *funcs;
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if (old) {
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/* (N -> N+1), (N != 0, 1) probes */
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for (nr_probes = 0; old[nr_probes].func; nr_probes++)
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- if (old[nr_probes].func == probe &&
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- old[nr_probes].data == data)
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+ if (old[nr_probes].func == tp_func->func &&
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+ old[nr_probes].data == tp_func->data)
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return ERR_PTR(-EEXIST);
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}
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/* + 2 : one for new probe, one for NULL func */
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@@ -128,33 +115,30 @@ tracepoint_entry_add_probe(struct tracepoint_entry *entry,
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return ERR_PTR(-ENOMEM);
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if (old)
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memcpy(new, old, nr_probes * sizeof(struct tracepoint_func));
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- new[nr_probes].func = probe;
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- new[nr_probes].data = data;
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+ new[nr_probes] = *tp_func;
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new[nr_probes + 1].func = NULL;
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- entry->refcount = nr_probes + 1;
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- entry->funcs = new;
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- debug_print_probes(entry);
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+ *funcs = new;
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+ debug_print_probes(*funcs);
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return old;
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}
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-static void *
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-tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
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- void *probe, void *data)
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+static void *func_remove(struct tracepoint_func **funcs,
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+ struct tracepoint_func *tp_func)
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{
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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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+ old = *funcs;
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if (!old)
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return ERR_PTR(-ENOENT);
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- debug_print_probes(entry);
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+ debug_print_probes(*funcs);
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/* (N -> M), (N > 1, M >= 0) probes */
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- if (probe) {
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+ if (tp_func->func) {
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for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
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- if (old[nr_probes].func == probe &&
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- old[nr_probes].data == data)
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+ if (old[nr_probes].func == tp_func->func &&
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+ old[nr_probes].data == tp_func->data)
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nr_del++;
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}
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}
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@@ -165,9 +149,8 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
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*/
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if (nr_probes - nr_del == 0) {
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/* N -> 0, (N > 1) */
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- entry->funcs = NULL;
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- entry->refcount = 0;
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- debug_print_probes(entry);
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+ *funcs = NULL;
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+ debug_print_probes(*funcs);
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return old;
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} else {
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int j = 0;
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@@ -177,91 +160,34 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
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if (new == NULL)
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return ERR_PTR(-ENOMEM);
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for (i = 0; old[i].func; i++)
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- if (old[i].func != probe || old[i].data != data)
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+ if (old[i].func != tp_func->func
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+ || old[i].data != tp_func->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;
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- entry->funcs = new;
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+ *funcs = new;
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}
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- debug_print_probes(entry);
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+ debug_print_probes(*funcs);
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return old;
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}
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/*
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- * Get tracepoint if the tracepoint is present in the tracepoint hash table.
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- * Must be called with tracepoints_mutex held.
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- * Returns NULL if not present.
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+ * Add the probe function to a tracepoint.
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*/
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-static struct tracepoint_entry *get_tracepoint(const char *name)
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+static int tracepoint_add_func(struct tracepoint *tp,
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+ struct tracepoint_func *func)
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{
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- struct hlist_head *head;
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- struct tracepoint_entry *e;
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- u32 hash = jhash(name, strlen(name), 0);
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-
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- head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
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- hlist_for_each_entry(e, head, hlist) {
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- if (!strcmp(name, e->name))
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- return e;
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- }
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- return NULL;
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-}
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+ struct tracepoint_func *old, *tp_funcs;
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-/*
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- * Add the tracepoint to the tracepoint hash table. Must be called with
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- * tracepoints_mutex held.
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- */
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-static struct tracepoint_entry *add_tracepoint(const char *name)
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-{
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- struct hlist_head *head;
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- struct tracepoint_entry *e;
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- size_t name_len = strlen(name) + 1;
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- u32 hash = jhash(name, name_len-1, 0);
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-
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- head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
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- hlist_for_each_entry(e, head, hlist) {
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- if (!strcmp(name, e->name)) {
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- printk(KERN_NOTICE
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- "tracepoint %s busy\n", name);
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- return ERR_PTR(-EEXIST); /* Already there */
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- }
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- }
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- /*
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- * Using kmalloc here to allocate a variable length element. Could
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- * cause some memory fragmentation if overused.
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- */
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- e = kmalloc(sizeof(struct tracepoint_entry) + name_len, GFP_KERNEL);
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- if (!e)
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- return ERR_PTR(-ENOMEM);
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- memcpy(&e->name[0], name, name_len);
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- e->funcs = NULL;
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- e->refcount = 0;
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- e->enabled = 0;
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- hlist_add_head(&e->hlist, head);
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- return e;
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-}
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+ if (tp->regfunc && !static_key_enabled(&tp->key))
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+ tp->regfunc();
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-/*
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- * Remove the tracepoint from the tracepoint hash table. Must be called with
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- * mutex_lock held.
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- */
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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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-}
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-
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-/*
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- * Sets the probe callback corresponding to one tracepoint.
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- */
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-static void set_tracepoint(struct tracepoint_entry **entry,
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- struct tracepoint *elem, int active)
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-{
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- WARN_ON(strcmp((*entry)->name, elem->name) != 0);
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-
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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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+ tp_funcs = tp->funcs;
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+ old = func_add(&tp_funcs, func);
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+ if (IS_ERR(old)) {
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+ WARN_ON_ONCE(1);
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+ return PTR_ERR(old);
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+ }
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+ release_probes(old);
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/*
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* rcu_assign_pointer has a smp_wmb() which makes sure that the new
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@@ -270,199 +196,163 @@ static void set_tracepoint(struct tracepoint_entry **entry,
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* include/linux/tracepoints.h. A matching smp_read_barrier_depends()
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* is used.
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*/
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- rcu_assign_pointer(elem->funcs, (*entry)->funcs);
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- if (active && !static_key_enabled(&elem->key))
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- static_key_slow_inc(&elem->key);
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- else if (!active && static_key_enabled(&elem->key))
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- static_key_slow_dec(&elem->key);
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+ rcu_assign_pointer(tp->funcs, tp_funcs);
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+ if (!static_key_enabled(&tp->key))
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+ static_key_slow_inc(&tp->key);
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+ return 0;
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}
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/*
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- * Disable a tracepoint and its probe callback.
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+ * Remove a probe function from a tracepoint.
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* Note: only waiting an RCU period after setting elem->call to the empty
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* function insures that the original callback is not used anymore. This insured
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* by preempt_disable around the call site.
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*/
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-static void disable_tracepoint(struct tracepoint *elem)
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+static int tracepoint_remove_func(struct tracepoint *tp,
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+ struct tracepoint_func *func)
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{
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- if (elem->unregfunc && static_key_enabled(&elem->key))
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- elem->unregfunc();
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-
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- if (static_key_enabled(&elem->key))
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- static_key_slow_dec(&elem->key);
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- rcu_assign_pointer(elem->funcs, NULL);
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-}
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+ struct tracepoint_func *old, *tp_funcs;
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-/**
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- * tracepoint_update_probe_range - Update a probe range
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- * @begin: beginning of the range
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- * @end: end of the range
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- *
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- * 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,
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- 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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-
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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);
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- mark_entry->enabled = !!mark_entry->refcount;
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- } else {
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- disable_tracepoint(*iter);
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- }
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+ tp_funcs = tp->funcs;
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+ old = func_remove(&tp_funcs, func);
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+ if (IS_ERR(old)) {
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+ WARN_ON_ONCE(1);
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+ return PTR_ERR(old);
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}
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-}
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-
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-#ifdef CONFIG_MODULES
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-void module_update_tracepoints(void)
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-{
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- struct tp_module *tp_mod;
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-
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- list_for_each_entry(tp_mod, &tracepoint_module_list, list)
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- tracepoint_update_probe_range(tp_mod->tracepoints_ptrs,
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- tp_mod->tracepoints_ptrs + tp_mod->num_tracepoints);
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-}
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-#else /* CONFIG_MODULES */
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-void module_update_tracepoints(void)
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-{
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-}
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-#endif /* CONFIG_MODULES */
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+ release_probes(old);
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+ if (!tp_funcs) {
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+ /* Removed last function */
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+ if (tp->unregfunc && static_key_enabled(&tp->key))
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+ tp->unregfunc();
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-/*
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- * Update probes, removing the faulty probes.
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- * Called with tracepoints_mutex held.
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- */
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-static void tracepoint_update_probes(void)
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-{
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- /* Core kernel tracepoints */
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- tracepoint_update_probe_range(__start___tracepoints_ptrs,
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- __stop___tracepoints_ptrs);
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- /* tracepoints in modules. */
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- module_update_tracepoints();
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-}
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-
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-static struct tracepoint_func *
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-tracepoint_add_probe(const char *name, void *probe, void *data)
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-{
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- struct tracepoint_entry *entry;
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- struct tracepoint_func *old;
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-
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- entry = get_tracepoint(name);
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- if (!entry) {
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- entry = add_tracepoint(name);
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- if (IS_ERR(entry))
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- return (struct tracepoint_func *)entry;
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+ if (static_key_enabled(&tp->key))
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+ static_key_slow_dec(&tp->key);
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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)
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- remove_tracepoint(entry);
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- return old;
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+ rcu_assign_pointer(tp->funcs, tp_funcs);
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+ return 0;
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}
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/**
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* tracepoint_probe_register - Connect a probe to a tracepoint
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- * @name: tracepoint name
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+ * @tp: tracepoint
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* @probe: probe handler
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- * @data: probe private data
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- *
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|
|
- * Returns:
|
|
|
- * - 0 if the probe was successfully registered, and tracepoint
|
|
|
- * callsites are currently loaded for that probe,
|
|
|
- * - -ENODEV if the probe was successfully registered, but no tracepoint
|
|
|
- * callsite is currently loaded for that probe,
|
|
|
- * - other negative error value on error.
|
|
|
- *
|
|
|
- * When tracepoint_probe_register() returns either 0 or -ENODEV,
|
|
|
- * parameters @name, @probe, and @data may be used by the tracepoint
|
|
|
- * infrastructure until the probe is unregistered.
|
|
|
*
|
|
|
- * The probe address must at least be aligned on the architecture pointer size.
|
|
|
+ * 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(const char *name, void *probe, void *data)
|
|
|
+int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data)
|
|
|
{
|
|
|
- struct tracepoint_func *old;
|
|
|
- struct tracepoint_entry *entry;
|
|
|
- int ret = 0;
|
|
|
+ struct tracepoint_func tp_func;
|
|
|
+ int ret;
|
|
|
|
|
|
mutex_lock(&tracepoints_mutex);
|
|
|
- old = tracepoint_add_probe(name, probe, data);
|
|
|
- if (IS_ERR(old)) {
|
|
|
- mutex_unlock(&tracepoints_mutex);
|
|
|
- return PTR_ERR(old);
|
|
|
- }
|
|
|
- tracepoint_update_probes(); /* may update entry */
|
|
|
- entry = get_tracepoint(name);
|
|
|
- /* Make sure the entry was enabled */
|
|
|
- if (!entry || !entry->enabled)
|
|
|
- ret = -ENODEV;
|
|
|
+ tp_func.func = probe;
|
|
|
+ tp_func.data = data;
|
|
|
+ ret = tracepoint_add_func(tp, &tp_func);
|
|
|
mutex_unlock(&tracepoints_mutex);
|
|
|
- release_probes(old);
|
|
|
return ret;
|
|
|
}
|
|
|
EXPORT_SYMBOL_GPL(tracepoint_probe_register);
|
|
|
|
|
|
-static struct tracepoint_func *
|
|
|
-tracepoint_remove_probe(const char *name, void *probe, void *data)
|
|
|
-{
|
|
|
- struct tracepoint_entry *entry;
|
|
|
- struct tracepoint_func *old;
|
|
|
-
|
|
|
- entry = get_tracepoint(name);
|
|
|
- if (!entry)
|
|
|
- return ERR_PTR(-ENOENT);
|
|
|
- old = tracepoint_entry_remove_probe(entry, probe, data);
|
|
|
- if (IS_ERR(old))
|
|
|
- return old;
|
|
|
- if (!entry->refcount)
|
|
|
- remove_tracepoint(entry);
|
|
|
- return old;
|
|
|
-}
|
|
|
-
|
|
|
/**
|
|
|
* tracepoint_probe_unregister - Disconnect a probe from a tracepoint
|
|
|
- * @name: tracepoint name
|
|
|
+ * @tp: tracepoint
|
|
|
* @probe: probe function pointer
|
|
|
- * @data: probe private data
|
|
|
*
|
|
|
- * 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.
|
|
|
+ * Returns 0 if ok, error value on error.
|
|
|
*/
|
|
|
-int tracepoint_probe_unregister(const char *name, void *probe, void *data)
|
|
|
+int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data)
|
|
|
{
|
|
|
- struct tracepoint_func *old;
|
|
|
+ struct tracepoint_func tp_func;
|
|
|
+ int ret;
|
|
|
|
|
|
mutex_lock(&tracepoints_mutex);
|
|
|
- old = tracepoint_remove_probe(name, probe, data);
|
|
|
- if (IS_ERR(old)) {
|
|
|
- mutex_unlock(&tracepoints_mutex);
|
|
|
- return PTR_ERR(old);
|
|
|
- }
|
|
|
- tracepoint_update_probes(); /* may update entry */
|
|
|
+ tp_func.func = probe;
|
|
|
+ tp_func.data = data;
|
|
|
+ ret = tracepoint_remove_func(tp, &tp_func);
|
|
|
mutex_unlock(&tracepoints_mutex);
|
|
|
- release_probes(old);
|
|
|
- return 0;
|
|
|
+ return ret;
|
|
|
}
|
|
|
EXPORT_SYMBOL_GPL(tracepoint_probe_unregister);
|
|
|
|
|
|
-
|
|
|
#ifdef CONFIG_MODULES
|
|
|
bool trace_module_has_bad_taint(struct module *mod)
|
|
|
{
|
|
|
return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP));
|
|
|
}
|
|
|
|
|
|
+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 * const *begin,
|
|
|
+ struct tracepoint * const *end)
|
|
|
+{
|
|
|
+ struct tracepoint * const *iter;
|
|
|
+
|
|
|
+ if (!begin)
|
|
|
+ return;
|
|
|
+ for (iter = begin; iter < end; iter++)
|
|
|
+ WARN_ON_ONCE((*iter)->funcs);
|
|
|
+}
|
|
|
+
|
|
|
static int tracepoint_module_coming(struct module *mod)
|
|
|
{
|
|
|
struct tp_module *tp_mod;
|
|
|
@@ -478,7 +368,7 @@ static int tracepoint_module_coming(struct module *mod)
|
|
|
*/
|
|
|
if (trace_module_has_bad_taint(mod))
|
|
|
return 0;
|
|
|
- mutex_lock(&tracepoints_mutex);
|
|
|
+ mutex_lock(&tracepoint_module_list_mutex);
|
|
|
tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL);
|
|
|
if (!tp_mod) {
|
|
|
ret = -ENOMEM;
|
|
|
@@ -487,27 +377,33 @@ static int tracepoint_module_coming(struct module *mod)
|
|
|
tp_mod->num_tracepoints = mod->num_tracepoints;
|
|
|
tp_mod->tracepoints_ptrs = mod->tracepoints_ptrs;
|
|
|
list_add_tail(&tp_mod->list, &tracepoint_module_list);
|
|
|
- tracepoint_update_probe_range(mod->tracepoints_ptrs,
|
|
|
- mod->tracepoints_ptrs + mod->num_tracepoints);
|
|
|
+ blocking_notifier_call_chain(&tracepoint_notify_list,
|
|
|
+ MODULE_STATE_COMING, tp_mod);
|
|
|
end:
|
|
|
- mutex_unlock(&tracepoints_mutex);
|
|
|
+ mutex_unlock(&tracepoint_module_list_mutex);
|
|
|
return ret;
|
|
|
}
|
|
|
|
|
|
-static int tracepoint_module_going(struct module *mod)
|
|
|
+static void tracepoint_module_going(struct module *mod)
|
|
|
{
|
|
|
- struct tp_module *pos;
|
|
|
+ struct tp_module *tp_mod;
|
|
|
|
|
|
if (!mod->num_tracepoints)
|
|
|
- return 0;
|
|
|
+ return;
|
|
|
|
|
|
- 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);
|
|
|
+ mutex_lock(&tracepoint_module_list_mutex);
|
|
|
+ list_for_each_entry(tp_mod, &tracepoint_module_list, list) {
|
|
|
+ if (tp_mod->tracepoints_ptrs == mod->tracepoints_ptrs) {
|
|
|
+ blocking_notifier_call_chain(&tracepoint_notify_list,
|
|
|
+ MODULE_STATE_GOING, tp_mod);
|
|
|
+ list_del(&tp_mod->list);
|
|
|
+ kfree(tp_mod);
|
|
|
+ /*
|
|
|
+ * Called the going notifier before checking for
|
|
|
+ * quiescence.
|
|
|
+ */
|
|
|
+ tp_module_going_check_quiescent(mod->tracepoints_ptrs,
|
|
|
+ mod->tracepoints_ptrs + mod->num_tracepoints);
|
|
|
break;
|
|
|
}
|
|
|
}
|
|
|
@@ -517,12 +413,11 @@ static int tracepoint_module_going(struct module *mod)
|
|
|
* flag on "going", in case a module taints the kernel only after being
|
|
|
* loaded.
|
|
|
*/
|
|
|
- mutex_unlock(&tracepoints_mutex);
|
|
|
- return 0;
|
|
|
+ mutex_unlock(&tracepoint_module_list_mutex);
|
|
|
}
|
|
|
|
|
|
-int tracepoint_module_notify(struct notifier_block *self,
|
|
|
- unsigned long val, void *data)
|
|
|
+static int tracepoint_module_notify(struct notifier_block *self,
|
|
|
+ unsigned long val, void *data)
|
|
|
{
|
|
|
struct module *mod = data;
|
|
|
int ret = 0;
|
|
|
@@ -534,24 +429,58 @@ int tracepoint_module_notify(struct notifier_block *self,
|
|
|
case MODULE_STATE_LIVE:
|
|
|
break;
|
|
|
case MODULE_STATE_GOING:
|
|
|
- ret = tracepoint_module_going(mod);
|
|
|
+ tracepoint_module_going(mod);
|
|
|
+ break;
|
|
|
+ case MODULE_STATE_UNFORMED:
|
|
|
break;
|
|
|
}
|
|
|
return ret;
|
|
|
}
|
|
|
|
|
|
-struct notifier_block tracepoint_module_nb = {
|
|
|
+static struct notifier_block tracepoint_module_nb = {
|
|
|
.notifier_call = tracepoint_module_notify,
|
|
|
.priority = 0,
|
|
|
};
|
|
|
|
|
|
-static int init_tracepoints(void)
|
|
|
+static __init int init_tracepoints(void)
|
|
|
{
|
|
|
- return register_module_notifier(&tracepoint_module_nb);
|
|
|
+ int ret;
|
|
|
+
|
|
|
+ ret = register_module_notifier(&tracepoint_module_nb);
|
|
|
+ if (ret) {
|
|
|
+ pr_warning("Failed to register tracepoint module enter notifier\n");
|
|
|
+ }
|
|
|
+ return ret;
|
|
|
}
|
|
|
__initcall(init_tracepoints);
|
|
|
#endif /* CONFIG_MODULES */
|
|
|
|
|
|
+static void for_each_tracepoint_range(struct tracepoint * const *begin,
|
|
|
+ struct tracepoint * const *end,
|
|
|
+ void (*fct)(struct tracepoint *tp, void *priv),
|
|
|
+ void *priv)
|
|
|
+{
|
|
|
+ struct tracepoint * const *iter;
|
|
|
+
|
|
|
+ if (!begin)
|
|
|
+ return;
|
|
|
+ for (iter = begin; iter < end; iter++)
|
|
|
+ fct(*iter, priv);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * for_each_kernel_tracepoint - iteration on all kernel tracepoints
|
|
|
+ * @fct: callback
|
|
|
+ * @priv: private data
|
|
|
+ */
|
|
|
+void for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv),
|
|
|
+ void *priv)
|
|
|
+{
|
|
|
+ for_each_tracepoint_range(__start___tracepoints_ptrs,
|
|
|
+ __stop___tracepoints_ptrs, fct, priv);
|
|
|
+}
|
|
|
+EXPORT_SYMBOL_GPL(for_each_kernel_tracepoint);
|
|
|
+
|
|
|
#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
|
|
|
|
|
|
/* NB: reg/unreg are called while guarded with the tracepoints_mutex */
|
Mathieu Desnoyers