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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c186
1 files changed, 123 insertions, 63 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 88de94da596b..08ea781540b5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -185,6 +185,7 @@ static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
static bool allocate_snapshot;
+static bool snapshot_at_boot;
static int __init set_cmdline_ftrace(char *str)
{
@@ -230,12 +231,21 @@ static int __init boot_alloc_snapshot(char *str)
__setup("alloc_snapshot", boot_alloc_snapshot);
+static int __init boot_snapshot(char *str)
+{
+ snapshot_at_boot = true;
+ boot_alloc_snapshot(str);
+ return 1;
+}
+__setup("ftrace_boot_snapshot", boot_snapshot);
+
+
static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata;
static int __init set_trace_boot_options(char *str)
{
strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
- return 0;
+ return 1;
}
__setup("trace_options=", set_trace_boot_options);
@@ -246,12 +256,16 @@ static int __init set_trace_boot_clock(char *str)
{
strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE);
trace_boot_clock = trace_boot_clock_buf;
- return 0;
+ return 1;
}
__setup("trace_clock=", set_trace_boot_clock);
static int __init set_tracepoint_printk(char *str)
{
+ /* Ignore the "tp_printk_stop_on_boot" param */
+ if (*str == '_')
+ return 0;
+
if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0))
tracepoint_printk = 1;
return 1;
@@ -980,6 +994,8 @@ __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *ev
ring_buffer_write(buffer, event->array[0], &event->array[1]);
/* Release the temp buffer */
this_cpu_dec(trace_buffered_event_cnt);
+ /* ring_buffer_unlock_commit() enables preemption */
+ preempt_enable_notrace();
} else
ring_buffer_unlock_commit(buffer, event);
}
@@ -1468,10 +1484,12 @@ static int __init set_buf_size(char *str)
if (!str)
return 0;
buf_size = memparse(str, &str);
- /* nr_entries can not be zero */
- if (buf_size == 0)
- return 0;
- trace_buf_size = buf_size;
+ /*
+ * nr_entries can not be zero and the startup
+ * tests require some buffer space. Therefore
+ * ensure we have at least 4096 bytes of buffer.
+ */
+ trace_buf_size = max(4096UL, buf_size);
return 1;
}
__setup("trace_buf_size=", set_buf_size);
@@ -2601,6 +2619,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
trace_flags |= TRACE_FLAG_HARDIRQ;
if (in_serving_softirq())
trace_flags |= TRACE_FLAG_SOFTIRQ;
+ if (softirq_count() >> (SOFTIRQ_SHIFT + 1))
+ trace_flags |= TRACE_FLAG_BH_OFF;
if (tif_need_resched())
trace_flags |= TRACE_FLAG_NEED_RESCHED;
@@ -2745,8 +2765,8 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
*current_rb = tr->array_buffer.buffer;
if (!tr->no_filter_buffering_ref &&
- (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) &&
- (entry = this_cpu_read(trace_buffered_event))) {
+ (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED))) {
+ preempt_disable_notrace();
/*
* Filtering is on, so try to use the per cpu buffer first.
* This buffer will simulate a ring_buffer_event,
@@ -2764,33 +2784,38 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
* is still quicker than no copy on match, but having
* to discard out of the ring buffer on a failed match.
*/
- int max_len = PAGE_SIZE - struct_size(entry, array, 1);
+ if ((entry = __this_cpu_read(trace_buffered_event))) {
+ int max_len = PAGE_SIZE - struct_size(entry, array, 1);
- val = this_cpu_inc_return(trace_buffered_event_cnt);
+ val = this_cpu_inc_return(trace_buffered_event_cnt);
- /*
- * Preemption is disabled, but interrupts and NMIs
- * can still come in now. If that happens after
- * the above increment, then it will have to go
- * back to the old method of allocating the event
- * on the ring buffer, and if the filter fails, it
- * will have to call ring_buffer_discard_commit()
- * to remove it.
- *
- * Need to also check the unlikely case that the
- * length is bigger than the temp buffer size.
- * If that happens, then the reserve is pretty much
- * guaranteed to fail, as the ring buffer currently
- * only allows events less than a page. But that may
- * change in the future, so let the ring buffer reserve
- * handle the failure in that case.
- */
- if (val == 1 && likely(len <= max_len)) {
- trace_event_setup(entry, type, trace_ctx);
- entry->array[0] = len;
- return entry;
+ /*
+ * Preemption is disabled, but interrupts and NMIs
+ * can still come in now. If that happens after
+ * the above increment, then it will have to go
+ * back to the old method of allocating the event
+ * on the ring buffer, and if the filter fails, it
+ * will have to call ring_buffer_discard_commit()
+ * to remove it.
+ *
+ * Need to also check the unlikely case that the
+ * length is bigger than the temp buffer size.
+ * If that happens, then the reserve is pretty much
+ * guaranteed to fail, as the ring buffer currently
+ * only allows events less than a page. But that may
+ * change in the future, so let the ring buffer reserve
+ * handle the failure in that case.
+ */
+ if (val == 1 && likely(len <= max_len)) {
+ trace_event_setup(entry, type, trace_ctx);
+ entry->array[0] = len;
+ /* Return with preemption disabled */
+ return entry;
+ }
+ this_cpu_dec(trace_buffered_event_cnt);
}
- this_cpu_dec(trace_buffered_event_cnt);
+ /* __trace_buffer_lock_reserve() disables preemption */
+ preempt_enable_notrace();
}
entry = __trace_buffer_lock_reserve(*current_rb, type, len,
@@ -3207,7 +3232,7 @@ struct trace_buffer_struct {
char buffer[4][TRACE_BUF_SIZE];
};
-static struct trace_buffer_struct *trace_percpu_buffer;
+static struct trace_buffer_struct __percpu *trace_percpu_buffer;
/*
* This allows for lockless recording. If we're nested too deeply, then
@@ -3217,7 +3242,7 @@ static char *get_trace_buf(void)
{
struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer);
- if (!buffer || buffer->nesting >= 4)
+ if (!trace_percpu_buffer || buffer->nesting >= 4)
return NULL;
buffer->nesting++;
@@ -3236,7 +3261,7 @@ static void put_trace_buf(void)
static int alloc_percpu_trace_buffer(void)
{
- struct trace_buffer_struct *buffers;
+ struct trace_buffer_struct __percpu *buffers;
if (trace_percpu_buffer)
return 0;
@@ -4183,7 +4208,7 @@ unsigned long trace_total_entries(struct trace_array *tr)
static void print_lat_help_header(struct seq_file *m)
{
seq_puts(m, "# _------=> CPU# \n"
- "# / _-----=> irqs-off \n"
+ "# / _-----=> irqs-off/BH-disabled\n"
"# | / _----=> need-resched \n"
"# || / _---=> hardirq/softirq \n"
"# ||| / _--=> preempt-depth \n"
@@ -4224,7 +4249,7 @@ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file
print_event_info(buf, m);
- seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space);
+ seq_printf(m, "# %.*s _-----=> irqs-off/BH-disabled\n", prec, space);
seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space);
seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space);
seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space);
@@ -4834,6 +4859,12 @@ int tracing_open_generic_tr(struct inode *inode, struct file *filp)
return 0;
}
+static int tracing_mark_open(struct inode *inode, struct file *filp)
+{
+ stream_open(inode, filp);
+ return tracing_open_generic_tr(inode, filp);
+}
+
static int tracing_release(struct inode *inode, struct file *file)
{
struct trace_array *tr = inode->i_private;
@@ -5635,7 +5666,7 @@ static const char readme_msg[] =
"\t - a numeric literal: e.g. ms_per_sec=1000,\n"
"\t - an arithmetic expression: e.g. time_secs=current_timestamp/1000\n"
"\n"
- "\t hist trigger aritmethic expressions support addition(+), subtraction(-),\n"
+ "\t hist trigger arithmetic expressions support addition(+), subtraction(-),\n"
"\t multiplication(*) and division(/) operators. An operand can be either a\n"
"\t variable reference, field or numeric literal.\n"
"\n"
@@ -6718,10 +6749,9 @@ waitagain:
cnt = PAGE_SIZE - 1;
/* reset all but tr, trace, and overruns */
- memset_startat(iter, 0, seq);
+ trace_iterator_reset(iter);
cpumask_clear(iter->started);
trace_seq_init(&iter->seq);
- iter->pos = -1;
trace_event_read_lock();
trace_access_lock(iter->cpu_file);
@@ -7110,9 +7140,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
if (tt)
event_triggers_post_call(tr->trace_marker_file, tt);
- if (written > 0)
- *fpos += written;
-
return written;
}
@@ -7171,9 +7198,6 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
__buffer_unlock_commit(buffer, event);
- if (written > 0)
- *fpos += written;
-
return written;
}
@@ -7573,16 +7597,14 @@ static const struct file_operations tracing_free_buffer_fops = {
};
static const struct file_operations tracing_mark_fops = {
- .open = tracing_open_generic_tr,
+ .open = tracing_mark_open,
.write = tracing_mark_write,
- .llseek = generic_file_llseek,
.release = tracing_release_generic_tr,
};
static const struct file_operations tracing_mark_raw_fops = {
- .open = tracing_open_generic_tr,
+ .open = tracing_mark_open,
.write = tracing_mark_raw_write,
- .llseek = generic_file_llseek,
.release = tracing_release_generic_tr,
};
@@ -7713,7 +7735,7 @@ const struct file_operations trace_min_max_fops = {
struct err_info {
const char **errs; /* ptr to loc-specific array of err strings */
u8 type; /* index into errs -> specific err string */
- u8 pos; /* MAX_FILTER_STR_VAL = 256 */
+ u16 pos; /* caret position */
u64 ts;
};
@@ -7721,25 +7743,52 @@ struct tracing_log_err {
struct list_head list;
struct err_info info;
char loc[TRACING_LOG_LOC_MAX]; /* err location */
- char cmd[MAX_FILTER_STR_VAL]; /* what caused err */
+ char *cmd; /* what caused err */
};
static DEFINE_MUTEX(tracing_err_log_lock);
-static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr)
+static struct tracing_log_err *alloc_tracing_log_err(int len)
+{
+ struct tracing_log_err *err;
+
+ err = kzalloc(sizeof(*err), GFP_KERNEL);
+ if (!err)
+ return ERR_PTR(-ENOMEM);
+
+ err->cmd = kzalloc(len, GFP_KERNEL);
+ if (!err->cmd) {
+ kfree(err);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return err;
+}
+
+static void free_tracing_log_err(struct tracing_log_err *err)
+{
+ kfree(err->cmd);
+ kfree(err);
+}
+
+static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr,
+ int len)
{
struct tracing_log_err *err;
if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) {
- err = kzalloc(sizeof(*err), GFP_KERNEL);
- if (!err)
- err = ERR_PTR(-ENOMEM);
- tr->n_err_log_entries++;
+ err = alloc_tracing_log_err(len);
+ if (PTR_ERR(err) != -ENOMEM)
+ tr->n_err_log_entries++;
return err;
}
err = list_first_entry(&tr->err_log, struct tracing_log_err, list);
+ kfree(err->cmd);
+ err->cmd = kzalloc(len, GFP_KERNEL);
+ if (!err->cmd)
+ return ERR_PTR(-ENOMEM);
list_del(&err->list);
return err;
@@ -7800,22 +7849,25 @@ unsigned int err_pos(char *cmd, const char *str)
*/
void tracing_log_err(struct trace_array *tr,
const char *loc, const char *cmd,
- const char **errs, u8 type, u8 pos)
+ const char **errs, u8 type, u16 pos)
{
struct tracing_log_err *err;
+ int len = 0;
if (!tr)
tr = &global_trace;
+ len += sizeof(CMD_PREFIX) + 2 * sizeof("\n") + strlen(cmd) + 1;
+
mutex_lock(&tracing_err_log_lock);
- err = get_tracing_log_err(tr);
+ err = get_tracing_log_err(tr, len);
if (PTR_ERR(err) == -ENOMEM) {
mutex_unlock(&tracing_err_log_lock);
return;
}
snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc);
- snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd);
+ snprintf(err->cmd, len, "\n" CMD_PREFIX "%s\n", cmd);
err->info.errs = errs;
err->info.type = type;
@@ -7833,7 +7885,7 @@ static void clear_tracing_err_log(struct trace_array *tr)
mutex_lock(&tracing_err_log_lock);
list_for_each_entry_safe(err, next, &tr->err_log, list) {
list_del(&err->list);
- kfree(err);
+ free_tracing_log_err(err);
}
tr->n_err_log_entries = 0;
@@ -7861,9 +7913,9 @@ static void tracing_err_log_seq_stop(struct seq_file *m, void *v)
mutex_unlock(&tracing_err_log_lock);
}
-static void tracing_err_log_show_pos(struct seq_file *m, u8 pos)
+static void tracing_err_log_show_pos(struct seq_file *m, u16 pos)
{
- u8 i;
+ u16 i;
for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++)
seq_putc(m, ' ');
@@ -10109,6 +10161,14 @@ out:
return ret;
}
+void __init ftrace_boot_snapshot(void)
+{
+ if (snapshot_at_boot) {
+ tracing_snapshot();
+ internal_trace_puts("** Boot snapshot taken **\n");
+ }
+}
+
void __init early_trace_init(void)
{
if (tracepoint_printk) {