unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX;
unsigned long __read_mostly tracing_thresh;
+static int tracing_disabled = 1;
+
static long notrace
ns2usecs(cycle_t nsec)
{
return nsec;
}
-static atomic_t tracer_counter;
+notrace cycle_t ftrace_now(int cpu)
+{
+ return cpu_clock(cpu);
+}
+
static struct trace_array global_trace;
static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
static DEFINE_PER_CPU(struct trace_array_cpu, max_data);
-static int tracer_enabled;
+static int tracer_enabled = 1;
static unsigned long trace_nr_entries = 16384UL;
static struct tracer *trace_types __read_mostly;
}
__setup("trace_entries=", set_nr_entries);
+unsigned long nsecs_to_usecs(unsigned long nsecs)
+{
+ return nsecs / 1000;
+}
+
enum trace_type {
__TRACE_FIRST_TYPE = 0,
TRACE_FN,
TRACE_CTX,
+ TRACE_SPECIAL,
__TRACE_LAST_TYPE
};
TRACE_ITER_SYM_OFFSET = 0x02,
TRACE_ITER_SYM_ADDR = 0x04,
TRACE_ITER_VERBOSE = 0x08,
+ TRACE_ITER_RAW = 0x10,
+ TRACE_ITER_BIN = 0x20,
};
#define TRACE_ITER_SYM_MASK \
"sym-offset",
"sym-addr",
"verbose",
+ "raw",
+ "bin",
NULL
};
* structure. (this way the maximum trace is permanently saved,
* for later retrieval via /debugfs/tracing/latency_trace)
*/
-static void notrace
+static notrace void
__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
struct trace_array_cpu *data = tr->data[cpu];
tracing_record_cmdline(current);
}
+void check_pages(struct trace_array_cpu *data)
+{
+ struct page *page, *tmp;
+
+ BUG_ON(data->trace_pages.next->prev != &data->trace_pages);
+ BUG_ON(data->trace_pages.prev->next != &data->trace_pages);
+
+ list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) {
+ BUG_ON(page->lru.next->prev != &page->lru);
+ BUG_ON(page->lru.prev->next != &page->lru);
+ }
+}
+
+void *head_page(struct trace_array_cpu *data)
+{
+ struct page *page;
+
+ check_pages(data);
+ if (list_empty(&data->trace_pages))
+ return NULL;
+
+ page = list_entry(data->trace_pages.next, struct page, lru);
+ BUG_ON(&page->lru == &data->trace_pages);
+
+ return page_address(page);
+}
+
+static notrace int
+trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ va_list ap;
+ int ret;
+
+ if (!len)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
+ va_end(ap);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret > len)
+ return 0;
+
+ s->len += ret;
+
+ return len;
+}
+
+static notrace int
+trace_seq_puts(struct trace_seq *s, const char *str)
+{
+ int len = strlen(str);
+
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, str, len);
+ s->len += len;
+
+ return len;
+}
+
+static notrace int
+trace_seq_putc(struct trace_seq *s, unsigned char c)
+{
+ if (s->len >= (PAGE_SIZE - 1))
+ return 0;
+
+ s->buffer[s->len++] = c;
+
+ return 1;
+}
+
+static notrace int
+trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
+{
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, mem, len);
+ s->len += len;
+
+ return len;
+}
+
+static notrace void
+trace_seq_reset(struct trace_seq *s)
+{
+ s->len = 0;
+}
+
+static notrace void
+trace_print_seq(struct seq_file *m, struct trace_seq *s)
+{
+ int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+
+ s->buffer[len] = 0;
+ seq_puts(m, s->buffer);
+
+ trace_seq_reset(s);
+}
+
+notrace static void
+flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2)
+{
+ struct list_head flip_pages;
+
+ INIT_LIST_HEAD(&flip_pages);
+
+ memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx,
+ sizeof(struct trace_array_cpu) -
+ offsetof(struct trace_array_cpu, trace_head_idx));
+
+ check_pages(tr1);
+ check_pages(tr2);
+ list_splice_init(&tr1->trace_pages, &flip_pages);
+ list_splice_init(&tr2->trace_pages, &tr1->trace_pages);
+ list_splice_init(&flip_pages, &tr2->trace_pages);
+ BUG_ON(!list_empty(&flip_pages));
+ check_pages(tr1);
+ check_pages(tr2);
+}
+
notrace void
update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
struct trace_array_cpu *data;
- void *save_trace;
- struct list_head save_pages;
int i;
WARN_ON_ONCE(!irqs_disabled());
/* clear out all the previous traces */
for_each_possible_cpu(i) {
data = tr->data[i];
- save_trace = max_tr.data[i]->trace;
- save_pages = max_tr.data[i]->trace_pages;
- memcpy(max_tr.data[i], data, sizeof(*data));
- data->trace = save_trace;
- data->trace_pages = save_pages;
+ flip_trace(max_tr.data[i], data);
+ tracing_reset(data);
}
__update_max_tr(tr, tsk, cpu);
update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
struct trace_array_cpu *data = tr->data[cpu];
- void *save_trace;
- struct list_head save_pages;
int i;
WARN_ON_ONCE(!irqs_disabled());
for_each_possible_cpu(i)
tracing_reset(max_tr.data[i]);
- save_trace = max_tr.data[cpu]->trace;
- save_pages = max_tr.data[cpu]->trace_pages;
- memcpy(max_tr.data[cpu], data, sizeof(*data));
- data->trace = save_trace;
- data->trace_pages = save_pages;
+ flip_trace(max_tr.data[cpu], data);
+ tracing_reset(data);
__update_max_tr(tr, tsk, cpu);
spin_unlock(&ftrace_max_lock);
}
}
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+ if (type->selftest) {
+ struct tracer *saved_tracer = current_trace;
+ struct trace_array_cpu *data;
+ struct trace_array *tr = &global_trace;
+ int saved_ctrl = tr->ctrl;
+ int i;
+ /*
+ * Run a selftest on this tracer.
+ * Here we reset the trace buffer, and set the current
+ * tracer to be this tracer. The tracer can then run some
+ * internal tracing to verify that everything is in order.
+ * If we fail, we do not register this tracer.
+ */
+ for_each_possible_cpu(i) {
+ data = tr->data[i];
+ if (!head_page(data))
+ continue;
+ tracing_reset(data);
+ }
+ current_trace = type;
+ tr->ctrl = 0;
+ /* the test is responsible for initializing and enabling */
+ pr_info("Testing tracer %s: ", type->name);
+ ret = type->selftest(type, tr);
+ /* the test is responsible for resetting too */
+ current_trace = saved_tracer;
+ tr->ctrl = saved_ctrl;
+ if (ret) {
+ printk(KERN_CONT "FAILED!\n");
+ goto out;
+ }
+ /* Only reset on passing, to avoid touching corrupted buffers */
+ for_each_possible_cpu(i) {
+ data = tr->data[i];
+ if (!head_page(data))
+ continue;
+ tracing_reset(data);
+ }
+ printk(KERN_CONT "PASSED\n");
+ }
+#endif
+
type->next = trace_types;
trace_types = type;
len = strlen(type->name);
if (len > max_tracer_type_len)
max_tracer_type_len = len;
+
out:
mutex_unlock(&trace_types_lock);
mutex_unlock(&trace_types_lock);
}
-void notrace tracing_reset(struct trace_array_cpu *data)
+notrace void tracing_reset(struct trace_array_cpu *data)
{
data->trace_idx = 0;
- data->trace_current = data->trace;
- data->trace_current_idx = 0;
-}
-
-#ifdef CONFIG_FTRACE
-static void notrace
-function_trace_call(unsigned long ip, unsigned long parent_ip)
-{
- struct trace_array *tr = &global_trace;
- struct trace_array_cpu *data;
- unsigned long flags;
- long disabled;
- int cpu;
-
- if (unlikely(!tracer_enabled))
- return;
-
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
- disabled = atomic_inc_return(&data->disabled);
-
- if (likely(disabled == 1))
- ftrace(tr, data, ip, parent_ip, flags);
-
- atomic_dec(&data->disabled);
- local_irq_restore(flags);
-}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = function_trace_call,
-};
-#endif
-
-notrace void tracing_start_function_trace(void)
-{
- register_ftrace_function(&trace_ops);
-}
-
-notrace void tracing_stop_function_trace(void)
-{
- unregister_ftrace_function(&trace_ops);
+ data->trace_head = data->trace_tail = head_page(data);
+ data->trace_head_idx = 0;
+ data->trace_tail_idx = 0;
}
#define SAVED_CMDLINES 128
notrace void trace_stop_cmdline_recording(void);
-static void notrace trace_save_cmdline(struct task_struct *tsk)
+static notrace void trace_save_cmdline(struct task_struct *tsk)
{
unsigned map;
unsigned idx;
trace_save_cmdline(tsk);
}
+static inline notrace struct list_head *
+trace_next_list(struct trace_array_cpu *data, struct list_head *next)
+{
+ /*
+ * Roundrobin - but skip the head (which is not a real page):
+ */
+ next = next->next;
+ if (unlikely(next == &data->trace_pages))
+ next = next->next;
+ BUG_ON(next == &data->trace_pages);
+
+ return next;
+}
+
+static inline notrace void *
+trace_next_page(struct trace_array_cpu *data, void *addr)
+{
+ struct list_head *next;
+ struct page *page;
+
+ page = virt_to_page(addr);
+
+ next = trace_next_list(data, &page->lru);
+ page = list_entry(next, struct page, lru);
+
+ return page_address(page);
+}
+
static inline notrace struct trace_entry *
-tracing_get_trace_entry(struct trace_array *tr,
- struct trace_array_cpu *data)
+tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data)
{
unsigned long idx, idx_next;
struct trace_entry *entry;
- struct page *page;
- struct list_head *next;
data->trace_idx++;
- idx = data->trace_current_idx;
+ idx = data->trace_head_idx;
idx_next = idx + 1;
- entry = data->trace_current + idx * TRACE_ENTRY_SIZE;
+ BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE);
+
+ entry = data->trace_head + idx * TRACE_ENTRY_SIZE;
if (unlikely(idx_next >= ENTRIES_PER_PAGE)) {
- page = virt_to_page(data->trace_current);
- if (unlikely(&page->lru == data->trace_pages.prev))
- next = data->trace_pages.next;
- else
- next = page->lru.next;
- page = list_entry(next, struct page, lru);
- data->trace_current = page_address(page);
+ data->trace_head = trace_next_page(data, data->trace_head);
idx_next = 0;
}
- data->trace_current_idx = idx_next;
+ if (data->trace_head == data->trace_tail &&
+ idx_next == data->trace_tail_idx) {
+ /* overrun */
+ data->trace_tail_idx++;
+ if (data->trace_tail_idx >= ENTRIES_PER_PAGE) {
+ data->trace_tail =
+ trace_next_page(data, data->trace_tail);
+ data->trace_tail_idx = 0;
+ }
+ }
+
+ data->trace_head_idx = idx_next;
return entry;
}
static inline notrace void
-tracing_generic_entry_update(struct trace_entry *entry,
- unsigned long flags)
+tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags)
{
struct task_struct *tsk = current;
unsigned long pc;
pc = preempt_count();
- entry->idx = atomic_inc_return(&tracer_counter);
- entry->preempt_count = pc & 0xff;
- entry->pid = tsk->pid;
- entry->t = now(raw_smp_processor_id());
+ entry->preempt_count = pc & 0xff;
+ entry->pid = tsk->pid;
+ entry->t = ftrace_now(raw_smp_processor_id());
entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
}
notrace void
-ftrace(struct trace_array *tr, struct trace_array_cpu *data,
- unsigned long ip, unsigned long parent_ip,
- unsigned long flags)
+__ftrace(struct trace_array *tr, struct trace_array_cpu *data,
+ unsigned long ip, unsigned long parent_ip, unsigned long flags)
{
struct trace_entry *entry;
+ unsigned long irq_flags;
- entry = tracing_get_trace_entry(tr, data);
+ spin_lock_irqsave(&data->lock, irq_flags);
+ entry = tracing_get_trace_entry(tr, data);
tracing_generic_entry_update(entry, flags);
- entry->type = TRACE_FN;
- entry->fn.ip = ip;
- entry->fn.parent_ip = parent_ip;
+ entry->type = TRACE_FN;
+ entry->fn.ip = ip;
+ entry->fn.parent_ip = parent_ip;
+ spin_unlock_irqrestore(&data->lock, irq_flags);
+}
+
+notrace void
+ftrace(struct trace_array *tr, struct trace_array_cpu *data,
+ unsigned long ip, unsigned long parent_ip, unsigned long flags)
+{
+ if (likely(!atomic_read(&data->disabled)))
+ __ftrace(tr, data, ip, parent_ip, flags);
+}
+
+notrace void
+trace_special(struct trace_array *tr, struct trace_array_cpu *data,
+ unsigned long arg1, unsigned long arg2, unsigned long arg3)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ spin_lock_irqsave(&data->lock, irq_flags);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, 0);
+ entry->type = TRACE_SPECIAL;
+ entry->special.arg1 = arg1;
+ entry->special.arg2 = arg2;
+ entry->special.arg3 = arg3;
+ spin_unlock_irqrestore(&data->lock, irq_flags);
}
notrace void
unsigned long flags)
{
struct trace_entry *entry;
+ unsigned long irq_flags;
- entry = tracing_get_trace_entry(tr, data);
+ spin_lock_irqsave(&data->lock, irq_flags);
+ entry = tracing_get_trace_entry(tr, data);
tracing_generic_entry_update(entry, flags);
entry->type = TRACE_CTX;
entry->ctx.prev_pid = prev->pid;
entry->ctx.prev_state = prev->state;
entry->ctx.next_pid = next->pid;
entry->ctx.next_prio = next->prio;
+ spin_unlock_irqrestore(&data->lock, irq_flags);
+}
+
+#ifdef CONFIG_FTRACE
+static notrace void
+function_trace_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ if (unlikely(!tracer_enabled))
+ return;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ __ftrace(tr, data, ip, parent_ip, flags);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
}
+static struct ftrace_ops trace_ops __read_mostly =
+{
+ .func = function_trace_call,
+};
+
+notrace void tracing_start_function_trace(void)
+{
+ register_ftrace_function(&trace_ops);
+}
+
+notrace void tracing_stop_function_trace(void)
+{
+ unregister_ftrace_function(&trace_ops);
+}
+#endif
+
enum trace_file_type {
TRACE_FILE_LAT_FMT = 1,
};
struct trace_entry *array;
if (iter->next_idx[cpu] >= tr->entries ||
- iter->next_idx[cpu] >= data->trace_idx)
+ iter->next_idx[cpu] >= data->trace_idx ||
+ (data->trace_head == data->trace_tail &&
+ data->trace_head_idx == data->trace_tail_idx))
return NULL;
if (!iter->next_page[cpu]) {
- /*
- * Initialize. If the count of elements in
- * this buffer is greater than the max entries
- * we had an underrun. Which means we looped around.
- * We can simply use the current pointer as our
- * starting point.
- */
- if (data->trace_idx >= tr->entries) {
- page = virt_to_page(data->trace_current);
- iter->next_page[cpu] = &page->lru;
- iter->next_page_idx[cpu] = data->trace_current_idx;
- } else {
- iter->next_page[cpu] = data->trace_pages.next;
- iter->next_page_idx[cpu] = 0;
- }
+ /* Initialize the iterator for this cpu trace buffer */
+ WARN_ON(!data->trace_tail);
+ page = virt_to_page(data->trace_tail);
+ iter->next_page[cpu] = &page->lru;
+ iter->next_page_idx[cpu] = data->trace_tail_idx;
}
page = list_entry(iter->next_page[cpu], struct page, lru);
+ BUG_ON(&data->trace_pages == &page->lru);
+
array = page_address(page);
+ WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE);
return &array[iter->next_page_idx[cpu]];
}
-static struct notrace trace_entry *
+static struct trace_entry * notrace
find_next_entry(struct trace_iterator *iter, int *ent_cpu)
{
struct trace_array *tr = iter->tr;
int cpu;
for_each_possible_cpu(cpu) {
- if (!tr->data[cpu]->trace)
+ if (!head_page(tr->data[cpu]))
continue;
ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu);
- if (ent &&
- (!next || (long)(next->idx - ent->idx) > 0)) {
+ /*
+ * Pick the entry with the smallest timestamp:
+ */
+ if (ent && (!next || ent->t < next->t)) {
next = ent;
next_cpu = cpu;
}
return next;
}
-static void *find_next_entry_inc(struct trace_iterator *iter)
+static notrace void trace_iterator_increment(struct trace_iterator *iter)
+{
+ iter->idx++;
+ iter->next_idx[iter->cpu]++;
+ iter->next_page_idx[iter->cpu]++;
+
+ if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) {
+ struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+
+ iter->next_page_idx[iter->cpu] = 0;
+ iter->next_page[iter->cpu] =
+ trace_next_list(data, iter->next_page[iter->cpu]);
+ }
+}
+
+static notrace void trace_consume(struct trace_iterator *iter)
+{
+ struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+
+ data->trace_tail_idx++;
+ if (data->trace_tail_idx >= ENTRIES_PER_PAGE) {
+ data->trace_tail = trace_next_page(data, data->trace_tail);
+ data->trace_tail_idx = 0;
+ }
+
+ /* Check if we empty it, then reset the index */
+ if (data->trace_head == data->trace_tail &&
+ data->trace_head_idx == data->trace_tail_idx)
+ data->trace_idx = 0;
+}
+
+static notrace void *find_next_entry_inc(struct trace_iterator *iter)
{
struct trace_entry *next;
int next_cpu = -1;
next = find_next_entry(iter, &next_cpu);
- if (next) {
- iter->idx++;
- iter->next_idx[next_cpu]++;
- iter->next_page_idx[next_cpu]++;
- if (iter->next_page_idx[next_cpu] >= ENTRIES_PER_PAGE) {
- struct trace_array_cpu *data = iter->tr->data[next_cpu];
-
- iter->next_page_idx[next_cpu] = 0;
- iter->next_page[next_cpu] =
- iter->next_page[next_cpu]->next;
- if (iter->next_page[next_cpu] == &data->trace_pages)
- iter->next_page[next_cpu] =
- data->trace_pages.next;
- }
- }
+ iter->prev_ent = iter->ent;
+ iter->prev_cpu = iter->cpu;
+
iter->ent = next;
iter->cpu = next_cpu;
+ if (next)
+ trace_iterator_increment(iter);
+
return next ? iter : NULL;
}
-static void notrace *
-s_next(struct seq_file *m, void *v, loff_t *pos)
+static notrace void *s_next(struct seq_file *m, void *v, loff_t *pos)
{
struct trace_iterator *iter = m->private;
- void *ent;
void *last_ent = iter->ent;
int i = (int)*pos;
+ void *ent;
(*pos)++;
iter->ent = NULL;
iter->cpu = 0;
iter->idx = -1;
+ iter->prev_ent = NULL;
+ iter->prev_cpu = -1;
for_each_possible_cpu(i) {
iter->next_idx[i] = 0;
mutex_unlock(&trace_types_lock);
}
-static void
-seq_print_sym_short(struct seq_file *m, const char *fmt, unsigned long address)
+static int
+seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
{
#ifdef CONFIG_KALLSYMS
char str[KSYM_SYMBOL_LEN];
kallsyms_lookup(address, NULL, NULL, NULL, str);
- seq_printf(m, fmt, str);
+ return trace_seq_printf(s, fmt, str);
#endif
+ return 1;
}
-static void
-seq_print_sym_offset(struct seq_file *m, const char *fmt, unsigned long address)
+static int
+seq_print_sym_offset(struct trace_seq *s, const char *fmt,
+ unsigned long address)
{
#ifdef CONFIG_KALLSYMS
char str[KSYM_SYMBOL_LEN];
sprint_symbol(str, address);
- seq_printf(m, fmt, str);
+ return trace_seq_printf(s, fmt, str);
#endif
+ return 1;
}
#ifndef CONFIG_64BIT
# define IP_FMT "%016lx"
#endif
-static void notrace
-seq_print_ip_sym(struct seq_file *m, unsigned long ip, unsigned long sym_flags)
+static notrace int
+seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
{
- if (!ip) {
- seq_printf(m, "0");
- return;
- }
+ int ret;
+
+ if (!ip)
+ return trace_seq_printf(s, "0");
if (sym_flags & TRACE_ITER_SYM_OFFSET)
- seq_print_sym_offset(m, "%s", ip);
+ ret = seq_print_sym_offset(s, "%s", ip);
else
- seq_print_sym_short(m, "%s", ip);
+ ret = seq_print_sym_short(s, "%s", ip);
+
+ if (!ret)
+ return 0;
if (sym_flags & TRACE_ITER_SYM_ADDR)
- seq_printf(m, " <" IP_FMT ">", ip);
+ ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
+ return ret;
}
-static void notrace print_lat_help_header(struct seq_file *m)
+static notrace void print_lat_help_header(struct seq_file *m)
{
seq_puts(m, "# _------=> CPU# \n");
seq_puts(m, "# / _-----=> irqs-off \n");
seq_puts(m, "# \\ / ||||| \\ | / \n");
}
-static void notrace print_func_help_header(struct seq_file *m)
+static notrace void print_func_help_header(struct seq_file *m)
{
seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n");
seq_puts(m, "# | | | | |\n");
}
-static void notrace
+static notrace void
print_trace_header(struct seq_file *m, struct trace_iterator *iter)
{
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
name = type->name;
for_each_possible_cpu(cpu) {
- if (tr->data[cpu]->trace) {
+ if (head_page(tr->data[cpu])) {
total += tr->data[cpu]->trace_idx;
if (tr->data[cpu]->trace_idx > tr->entries)
entries += tr->entries;
"---------------------------------\n");
seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |"
" (M:%s VP:%d, KP:%d, SP:%d HP:%d",
- data->saved_latency,
+ nsecs_to_usecs(data->saved_latency),
entries,
total,
tr->cpu,
if (data->critical_start) {
seq_puts(m, " => started at: ");
- seq_print_ip_sym(m, data->critical_start, sym_flags);
+ seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags);
+ trace_print_seq(m, &iter->seq);
seq_puts(m, "\n => ended at: ");
- seq_print_ip_sym(m, data->critical_end, sym_flags);
+ seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
+ trace_print_seq(m, &iter->seq);
seq_puts(m, "\n");
}
seq_puts(m, "\n");
}
-unsigned long nsecs_to_usecs(unsigned long nsecs)
-{
- return nsecs / 1000;
-}
-
-static void notrace
-lat_print_generic(struct seq_file *m, struct trace_entry *entry, int cpu)
+static notrace void
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
{
int hardirq, softirq;
char *comm;
comm = trace_find_cmdline(entry->pid);
- seq_printf(m, "%8.8s-%-5d ", comm, entry->pid);
- seq_printf(m, "%d", cpu);
- seq_printf(m, "%c%c",
- (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.',
- ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.'));
+ trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid);
+ trace_seq_printf(s, "%d", cpu);
+ trace_seq_printf(s, "%c%c",
+ (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.',
+ ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.'));
hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
if (hardirq && softirq)
- seq_putc(m, 'H');
+ trace_seq_putc(s, 'H');
else {
if (hardirq)
- seq_putc(m, 'h');
+ trace_seq_putc(s, 'h');
else {
if (softirq)
- seq_putc(m, 's');
+ trace_seq_putc(s, 's');
else
- seq_putc(m, '.');
+ trace_seq_putc(s, '.');
}
}
if (entry->preempt_count)
- seq_printf(m, "%x", entry->preempt_count);
+ trace_seq_printf(s, "%x", entry->preempt_count);
else
- seq_puts(m, ".");
+ trace_seq_puts(s, ".");
}
unsigned long preempt_mark_thresh = 100;
-static void notrace
-lat_print_timestamp(struct seq_file *m, unsigned long long abs_usecs,
+static notrace void
+lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs,
unsigned long rel_usecs)
{
- seq_printf(m, " %4lldus", abs_usecs);
+ trace_seq_printf(s, " %4lldus", abs_usecs);
if (rel_usecs > preempt_mark_thresh)
- seq_puts(m, "!: ");
+ trace_seq_puts(s, "!: ");
else if (rel_usecs > 1)
- seq_puts(m, "+: ");
+ trace_seq_puts(s, "+: ");
else
- seq_puts(m, " : ");
+ trace_seq_puts(s, " : ");
}
static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
-static void notrace
-print_lat_fmt(struct seq_file *m, struct trace_iterator *iter,
- unsigned int trace_idx, int cpu)
+static notrace int
+print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
{
+ struct trace_seq *s = &iter->seq;
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
struct trace_entry *next_entry = find_next_entry(iter, NULL);
unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
if (verbose) {
comm = trace_find_cmdline(entry->pid);
- seq_printf(m, "%16s %5d %d %d %08x %08x [%08lx]"
- " %ld.%03ldms (+%ld.%03ldms): ",
- comm,
- entry->pid, cpu, entry->flags,
- entry->preempt_count, trace_idx,
- ns2usecs(entry->t),
- abs_usecs/1000,
- abs_usecs % 1000, rel_usecs/1000, rel_usecs % 1000);
+ trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]"
+ " %ld.%03ldms (+%ld.%03ldms): ",
+ comm,
+ entry->pid, cpu, entry->flags,
+ entry->preempt_count, trace_idx,
+ ns2usecs(entry->t),
+ abs_usecs/1000,
+ abs_usecs % 1000, rel_usecs/1000,
+ rel_usecs % 1000);
} else {
- lat_print_generic(m, entry, cpu);
- lat_print_timestamp(m, abs_usecs, rel_usecs);
+ lat_print_generic(s, entry, cpu);
+ lat_print_timestamp(s, abs_usecs, rel_usecs);
}
switch (entry->type) {
case TRACE_FN:
- seq_print_ip_sym(m, entry->fn.ip, sym_flags);
- seq_puts(m, " (");
- seq_print_ip_sym(m, entry->fn.parent_ip, sym_flags);
- seq_puts(m, ")\n");
+ seq_print_ip_sym(s, entry->fn.ip, sym_flags);
+ trace_seq_puts(s, " (");
+ seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags);
+ trace_seq_puts(s, ")\n");
break;
case TRACE_CTX:
S = entry->ctx.prev_state < sizeof(state_to_char) ?
state_to_char[entry->ctx.prev_state] : 'X';
comm = trace_find_cmdline(entry->ctx.next_pid);
- seq_printf(m, " %d:%d:%c --> %d:%d %s\n",
- entry->ctx.prev_pid,
- entry->ctx.prev_prio,
- S,
- entry->ctx.next_pid,
- entry->ctx.next_prio,
- comm);
+ trace_seq_printf(s, " %d:%d:%c --> %d:%d %s\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S,
+ entry->ctx.next_pid,
+ entry->ctx.next_prio,
+ comm);
+ break;
+ case TRACE_SPECIAL:
+ trace_seq_printf(s, " %lx %lx %lx\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
break;
+ default:
+ trace_seq_printf(s, "Unknown type %d\n", entry->type);
}
+ return 1;
}
-static void notrace
-print_trace_fmt(struct seq_file *m, struct trace_iterator *iter)
+static notrace int print_trace_fmt(struct trace_iterator *iter)
{
+ struct trace_seq *s = &iter->seq;
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
- struct trace_entry *entry = iter->ent;
+ struct trace_entry *entry;
unsigned long usec_rem;
unsigned long long t;
unsigned long secs;
char *comm;
int S;
+ int ret;
+
+ entry = iter->ent;
comm = trace_find_cmdline(iter->ent->pid);
usec_rem = do_div(t, 1000000ULL);
secs = (unsigned long)t;
- seq_printf(m, "%16s-%-5d ", comm, entry->pid);
- seq_printf(m, "[%02d] ", iter->cpu);
- seq_printf(m, "%5lu.%06lu: ", secs, usec_rem);
+ ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid);
+ if (!ret)
+ return 0;
+ ret = trace_seq_printf(s, "[%02d] ", iter->cpu);
+ if (!ret)
+ return 0;
+ ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem);
+ if (!ret)
+ return 0;
switch (entry->type) {
case TRACE_FN:
- seq_print_ip_sym(m, entry->fn.ip, sym_flags);
+ ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags);
+ if (!ret)
+ return 0;
if ((sym_flags & TRACE_ITER_PRINT_PARENT) &&
entry->fn.parent_ip) {
- seq_printf(m, " <-");
- seq_print_ip_sym(m, entry->fn.parent_ip, sym_flags);
+ ret = trace_seq_printf(s, " <-");
+ if (!ret)
+ return 0;
+ ret = seq_print_ip_sym(s, entry->fn.parent_ip,
+ sym_flags);
+ if (!ret)
+ return 0;
}
+ ret = trace_seq_printf(s, "\n");
+ if (!ret)
+ return 0;
break;
case TRACE_CTX:
S = entry->ctx.prev_state < sizeof(state_to_char) ?
state_to_char[entry->ctx.prev_state] : 'X';
- seq_printf(m, " %d:%d:%c ==> %d:%d\n",
- entry->ctx.prev_pid,
- entry->ctx.prev_prio,
- S,
- entry->ctx.next_pid,
- entry->ctx.next_prio);
+ ret = trace_seq_printf(s, " %d:%d:%c ==> %d:%d\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S,
+ entry->ctx.next_pid,
+ entry->ctx.next_prio);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_SPECIAL:
+ ret = trace_seq_printf(s, " %lx %lx %lx\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
+ if (!ret)
+ return 0;
+ break;
+ }
+ return 1;
+}
+
+static notrace int print_raw_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry;
+ int ret;
+ int S;
+
+ entry = iter->ent;
+
+ ret = trace_seq_printf(s, "%d %d %llu ",
+ entry->pid, iter->cpu, entry->t);
+ if (!ret)
+ return 0;
+
+ switch (entry->type) {
+ case TRACE_FN:
+ ret = trace_seq_printf(s, "%x %x\n",
+ entry->fn.ip, entry->fn.parent_ip);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_CTX:
+ S = entry->ctx.prev_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.prev_state] : 'X';
+ ret = trace_seq_printf(s, "%d %d %c %d %d\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S,
+ entry->ctx.next_pid,
+ entry->ctx.next_prio);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_SPECIAL:
+ ret = trace_seq_printf(s, " %lx %lx %lx\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
+ if (!ret)
+ return 0;
break;
}
- seq_printf(m, "\n");
+ return 1;
+}
+
+#define SEQ_PUT_FIELD_RET(s, x) \
+do { \
+ if (!trace_seq_putmem(s, &(x), sizeof(x))) \
+ return 0; \
+} while (0)
+
+static notrace int print_bin_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry;
+
+ entry = iter->ent;
+
+ SEQ_PUT_FIELD_RET(s, entry->pid);
+ SEQ_PUT_FIELD_RET(s, entry->cpu);
+ SEQ_PUT_FIELD_RET(s, entry->t);
+
+ switch (entry->type) {
+ case TRACE_FN:
+ SEQ_PUT_FIELD_RET(s, entry->fn.ip);
+ SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip);
+ break;
+ case TRACE_CTX:
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio);
+ break;
+ case TRACE_SPECIAL:
+ SEQ_PUT_FIELD_RET(s, entry->special.arg1);
+ SEQ_PUT_FIELD_RET(s, entry->special.arg2);
+ SEQ_PUT_FIELD_RET(s, entry->special.arg3);
+ break;
+ }
+ return 1;
}
static int trace_empty(struct trace_iterator *iter)
for_each_possible_cpu(cpu) {
data = iter->tr->data[cpu];
- if (data->trace &&
- data->trace_idx)
+ if (head_page(data) && data->trace_idx &&
+ (data->trace_tail != data->trace_head ||
+ data->trace_tail_idx != data->trace_head_idx))
return 0;
}
return 1;
}
+static int print_trace_line(struct trace_iterator *iter)
+{
+ if (trace_flags & TRACE_ITER_BIN)
+ return print_bin_fmt(iter);
+
+ if (trace_flags & TRACE_ITER_RAW)
+ return print_raw_fmt(iter);
+
+ if (iter->iter_flags & TRACE_FILE_LAT_FMT)
+ return print_lat_fmt(iter, iter->idx, iter->cpu);
+
+ return print_trace_fmt(iter);
+}
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
print_func_help_header(m);
}
} else {
- if (iter->iter_flags & TRACE_FILE_LAT_FMT)
- print_lat_fmt(m, iter, iter->idx, iter->cpu);
- else
- print_trace_fmt(m, iter);
+ print_trace_line(iter);
+ trace_print_seq(m, &iter->seq);
}
return 0;
}
static struct seq_operations tracer_seq_ops = {
- .start = s_start,
- .next = s_next,
- .stop = s_stop,
- .show = s_show,
+ .start = s_start,
+ .next = s_next,
+ .stop = s_stop,
+ .show = s_show,
};
static struct trace_iterator notrace *
{
struct trace_iterator *iter;
+ if (tracing_disabled) {
+ *ret = -ENODEV;
+ return NULL;
+ }
+
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
*ret = -ENOMEM;
int tracing_open_generic(struct inode *inode, struct file *filp)
{
+ if (tracing_disabled)
+ return -ENODEV;
+
filp->private_data = inode->i_private;
return 0;
}
}
-static void notrace *
+static notrace void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
struct tracer *t = m->private;
}
static struct seq_operations show_traces_seq_ops = {
- .start = t_start,
- .next = t_next,
- .stop = t_stop,
- .show = t_show,
+ .start = t_start,
+ .next = t_next,
+ .stop = t_stop,
+ .show = t_show,
};
static int show_traces_open(struct inode *inode, struct file *file)
{
int ret;
+ if (tracing_disabled)
+ return -ENODEV;
+
ret = seq_open(file, &show_traces_seq_ops);
if (!ret) {
struct seq_file *m = file->private_data;
}
static struct file_operations tracing_fops = {
- .open = tracing_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = tracing_release,
+ .open = tracing_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_release,
};
static struct file_operations tracing_lt_fops = {
- .open = tracing_lt_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = tracing_release,
+ .open = tracing_lt_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_release,
};
static struct file_operations show_traces_fops = {
.write = tracing_iter_ctrl_write,
};
+static const char readme_msg[] =
+ "tracing mini-HOWTO:\n\n"
+ "# mkdir /debug\n"
+ "# mount -t debugfs nodev /debug\n\n"
+ "# cat /debug/tracing/available_tracers\n"
+ "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n"
+ "# cat /debug/tracing/current_tracer\n"
+ "none\n"
+ "# echo sched_switch > /debug/tracing/current_tracer\n"
+ "# cat /debug/tracing/current_tracer\n"
+ "sched_switch\n"
+ "# cat /debug/tracing/iter_ctrl\n"
+ "noprint-parent nosym-offset nosym-addr noverbose\n"
+ "# echo print-parent > /debug/tracing/iter_ctrl\n"
+ "# echo 1 > /debug/tracing/tracing_enabled\n"
+ "# cat /debug/tracing/trace > /tmp/trace.txt\n"
+ "echo 0 > /debug/tracing/tracing_enabled\n"
+;
+
+static ssize_t
+tracing_readme_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return simple_read_from_buffer(ubuf, cnt, ppos,
+ readme_msg, strlen(readme_msg));
+}
+
+static struct file_operations tracing_readme_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_readme_read,
+};
+
+
static ssize_t
tracing_ctrl_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
int r;
r = sprintf(buf, "%ld\n", tr->ctrl);
- return simple_read_from_buffer(ubuf, cnt, ppos,
- buf, r);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
static ssize_t
r = sprintf(buf, "\n");
mutex_unlock(&trace_types_lock);
- return simple_read_from_buffer(ubuf, cnt, ppos,
- buf, r);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
static ssize_t
*ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr));
if (r > 64)
r = 64;
- return simple_read_from_buffer(ubuf, cnt, ppos,
- buf, r);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
static ssize_t
return cnt;
}
+static atomic_t tracing_reader;
+
+static int tracing_open_pipe(struct inode *inode, struct file *filp)
+{
+ struct trace_iterator *iter;
+
+ if (tracing_disabled)
+ return -ENODEV;
+
+ /* We only allow for reader of the pipe */
+ if (atomic_inc_return(&tracing_reader) != 1) {
+ atomic_dec(&tracing_reader);
+ return -EBUSY;
+ }
+
+ /* create a buffer to store the information to pass to userspace */
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ iter->tr = &global_trace;
+
+ filp->private_data = iter;
+
+ return 0;
+}
+
+static int tracing_release_pipe(struct inode *inode, struct file *file)
+{
+ struct trace_iterator *iter = file->private_data;
+
+ kfree(iter);
+ atomic_dec(&tracing_reader);
+
+ return 0;
+}
+
+/*
+ * Consumer reader.
+ */
+static ssize_t
+tracing_read_pipe(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_iterator *iter = filp->private_data;
+ struct trace_array_cpu *data;
+ static cpumask_t mask;
+ static int start;
+ unsigned long flags;
+ int ftrace_save;
+ int read = 0;
+ int cpu;
+ int len;
+ int ret;
+
+ /* return any leftover data */
+ if (iter->seq.len > start) {
+ len = iter->seq.len - start;
+ if (cnt > len)
+ cnt = len;
+ ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt);
+ if (ret)
+ cnt = -EFAULT;
+
+ start += len;
+
+ return cnt;
+ }
+
+ trace_seq_reset(&iter->seq);
+ start = 0;
+
+ while (trace_empty(iter)) {
+ /*
+ * This is a make-shift waitqueue. The reason we don't use
+ * an actual wait queue is because:
+ * 1) we only ever have one waiter
+ * 2) the tracing, traces all functions, we don't want
+ * the overhead of calling wake_up and friends
+ * (and tracing them too)
+ * Anyway, this is really very primitive wakeup.
+ */
+ set_current_state(TASK_INTERRUPTIBLE);
+ iter->tr->waiter = current;
+
+ /* sleep for one second, and try again. */
+ schedule_timeout(HZ);
+
+ iter->tr->waiter = NULL;
+
+ if (signal_pending(current))
+ return -EINTR;
+
+ /*
+ * We block until we read something and tracing is disabled.
+ * We still block if tracing is disabled, but we have never
+ * read anything. This allows a user to cat this file, and
+ * then enable tracing. But after we have read something,
+ * we give an EOF when tracing is again disabled.
+ *
+ * iter->pos will be 0 if we haven't read anything.
+ */
+ if (!tracer_enabled && iter->pos)
+ break;
+
+ continue;
+ }
+
+ /* stop when tracing is finished */
+ if (trace_empty(iter))
+ return 0;
+
+ if (cnt >= PAGE_SIZE)
+ cnt = PAGE_SIZE - 1;
+
+ memset(iter, 0, sizeof(*iter));
+ iter->tr = &global_trace;
+ iter->pos = -1;
+
+ /*
+ * We need to stop all tracing on all CPUS to read the
+ * the next buffer. This is a bit expensive, but is
+ * not done often. We fill all what we can read,
+ * and then release the locks again.
+ */
+
+ cpus_clear(mask);
+ local_irq_save(flags);
+ ftrace_save = ftrace_enabled;
+ ftrace_enabled = 0;
+ smp_wmb();
+ for_each_possible_cpu(cpu) {
+ data = iter->tr->data[cpu];
+
+ if (!head_page(data) || !data->trace_idx)
+ continue;
+
+ atomic_inc(&data->disabled);
+ cpu_set(cpu, mask);
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ spin_lock(&data->lock);
+ }
+
+ while (find_next_entry_inc(iter) != NULL) {
+ int len = iter->seq.len;
+
+ ret = print_trace_line(iter);
+ if (!ret) {
+ /* don't print partial lines */
+ iter->seq.len = len;
+ break;
+ }
+
+ trace_consume(iter);
+
+ if (iter->seq.len >= cnt)
+ break;
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ spin_unlock(&data->lock);
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ atomic_dec(&data->disabled);
+ }
+ ftrace_enabled = ftrace_save;
+ local_irq_restore(flags);
+
+ /* Now copy what we have to the user */
+ read = iter->seq.len;
+ if (read > cnt)
+ read = cnt;
+
+ ret = copy_to_user(ubuf, iter->seq.buffer, read);
+
+ if (read < iter->seq.len)
+ start = read;
+ else
+ trace_seq_reset(&iter->seq);
+
+ if (ret)
+ read = -EFAULT;
+
+ return read;
+}
+
static struct file_operations tracing_max_lat_fops = {
- .open = tracing_open_generic,
- .read = tracing_max_lat_read,
- .write = tracing_max_lat_write,
+ .open = tracing_open_generic,
+ .read = tracing_max_lat_read,
+ .write = tracing_max_lat_write,
};
static struct file_operations tracing_ctrl_fops = {
- .open = tracing_open_generic,
- .read = tracing_ctrl_read,
- .write = tracing_ctrl_write,
+ .open = tracing_open_generic,
+ .read = tracing_ctrl_read,
+ .write = tracing_ctrl_write,
};
static struct file_operations set_tracer_fops = {
- .open = tracing_open_generic,
- .read = tracing_set_trace_read,
- .write = tracing_set_trace_write,
+ .open = tracing_open_generic,
+ .read = tracing_set_trace_read,
+ .write = tracing_set_trace_write,
+};
+
+static struct file_operations tracing_pipe_fops = {
+ .open = tracing_open_pipe,
+ .read = tracing_read_pipe,
+ .release = tracing_release_pipe,
};
#ifdef CONFIG_DYNAMIC_FTRACE
int r;
r = sprintf(buf, "%ld\n", *p);
- return simple_read_from_buffer(ubuf, cnt, ppos,
- buf, r);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
static struct file_operations tracing_read_long_fops = {
- .open = tracing_open_generic,
- .read = tracing_read_long,
+ .open = tracing_open_generic,
+ .read = tracing_read_long,
};
#endif
return d_tracer;
}
+#ifdef CONFIG_FTRACE_SELFTEST
+/* Let selftest have access to static functions in this file */
+#include "trace_selftest.c"
+#endif
+
static __init void tracer_init_debugfs(void)
{
struct dentry *d_tracer;
if (!entry)
pr_warning("Could not create debugfs "
"'tracing_threash' entry\n");
+ entry = debugfs_create_file("README", 0644, d_tracer,
+ NULL, &tracing_readme_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'README' entry\n");
+
+ entry = debugfs_create_file("trace_pipe", 0644, d_tracer,
+ NULL, &tracing_pipe_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'tracing_threash' entry\n");
#ifdef CONFIG_DYNAMIC_FTRACE
entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
/* dummy trace to disable tracing */
static struct tracer no_tracer __read_mostly =
{
- .name = "none",
+ .name = "none",
};
static int trace_alloc_page(void)
{
struct trace_array_cpu *data;
- void *array;
struct page *page, *tmp;
LIST_HEAD(pages);
+ void *array;
int i;
/* first allocate a page for each CPU */
/* Now that we successfully allocate a page per CPU, add them */
for_each_possible_cpu(i) {
data = global_trace.data[i];
+ spin_lock_init(&data->lock);
+ lockdep_set_class(&data->lock, &data->lock_key);
page = list_entry(pages.next, struct page, lru);
- list_del(&page->lru);
+ list_del_init(&page->lru);
list_add_tail(&page->lru, &data->trace_pages);
ClearPageLRU(page);
#ifdef CONFIG_TRACER_MAX_TRACE
data = max_tr.data[i];
+ spin_lock_init(&data->lock);
+ lockdep_set_class(&data->lock, &data->lock_key);
page = list_entry(pages.next, struct page, lru);
- list_del(&page->lru);
+ list_del_init(&page->lru);
list_add_tail(&page->lru, &data->trace_pages);
SetPageLRU(page);
#endif
free_pages:
list_for_each_entry_safe(page, tmp, &pages, lru) {
- list_del(&page->lru);
+ list_del_init(&page->lru);
__free_page(page);
}
return -ENOMEM;
void *array;
struct page *page;
int pages = 0;
+ int ret = -ENOMEM;
int i;
+ global_trace.ctrl = tracer_enabled;
+
/* Allocate the first page for all buffers */
for_each_possible_cpu(i) {
data = global_trace.data[i] = &per_cpu(global_trace_cpu, i);
"for trace buffer!\n");
goto free_buffers;
}
- data->trace = array;
/* set the array to the list */
INIT_LIST_HEAD(&data->trace_pages);
"for trace buffer!\n");
goto free_buffers;
}
- max_tr.data[i]->trace = array;
INIT_LIST_HEAD(&max_tr.data[i]->trace_pages);
page = virt_to_page(array);
* round up a bit.
*/
global_trace.entries = ENTRIES_PER_PAGE;
- max_tr.entries = global_trace.entries;
pages++;
while (global_trace.entries < trace_nr_entries) {
break;
pages++;
}
+ max_tr.entries = global_trace.entries;
pr_info("tracer: %d pages allocated for %ld",
pages, trace_nr_entries);
register_tracer(&no_tracer);
current_trace = &no_tracer;
+ /* All seems OK, enable tracing */
+ tracing_disabled = 0;
+
return 0;
free_buffers:
struct page *page, *tmp;
struct trace_array_cpu *data = global_trace.data[i];
- if (data && data->trace) {
+ if (data) {
list_for_each_entry_safe(page, tmp,
&data->trace_pages, lru) {
- list_del(&page->lru);
+ list_del_init(&page->lru);
__free_page(page);
}
- data->trace = NULL;
}
#ifdef CONFIG_TRACER_MAX_TRACE
data = max_tr.data[i];
- if (data && data->trace) {
+ if (data) {
list_for_each_entry_safe(page, tmp,
&data->trace_pages, lru) {
- list_del(&page->lru);
+ list_del_init(&page->lru);
__free_page(page);
}
- data->trace = NULL;
}
#endif
}
- return -ENOMEM;
+ return ret;
}
-
-device_initcall(tracer_alloc_buffers);
+fs_initcall(tracer_alloc_buffers);
projects / deliverable / linux.git / blobdiff