Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bf6f1d7..6a0ee91 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -17,6 +17,7 @@
#include <linux/stacktrace.h>
#include <linux/writeback.h>
#include <linux/kallsyms.h>
+#include <linux/security.h>
#include <linux/seq_file.h>
#include <linux/notifier.h>
#include <linux/irqflags.h>
@@ -159,6 +160,8 @@
#endif /* CONFIG_TRACE_EVAL_MAP_FILE */
static int tracing_set_tracer(struct trace_array *tr, const char *buf);
+static void ftrace_trace_userstack(struct ring_buffer *buffer,
+ unsigned long flags, int pc);
#define MAX_TRACER_SIZE 100
static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
@@ -302,6 +305,23 @@
mutex_unlock(&trace_types_lock);
}
+int tracing_check_open_get_tr(struct trace_array *tr)
+{
+ int ret;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
+
+ if (tracing_disabled)
+ return -ENODEV;
+
+ if (tr && trace_array_get(tr) < 0)
+ return -ENODEV;
+
+ return 0;
+}
+
int call_filter_check_discard(struct trace_event_call *call, void *rec,
struct ring_buffer *buffer,
struct ring_buffer_event *event)
@@ -364,7 +384,7 @@
}
/**
- * trace_pid_filter_add_remove_task - Add or remove a task from a pid_list
+ * trace_filter_add_remove_task - Add or remove a task from a pid_list
* @pid_list: The list to modify
* @self: The current task for fork or NULL for exit
* @task: The task to add or remove
@@ -496,8 +516,10 @@
* not modified.
*/
pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
- if (!pid_list)
+ if (!pid_list) {
+ trace_parser_put(&parser);
return -ENOMEM;
+ }
pid_list->pid_max = READ_ONCE(pid_max);
@@ -507,6 +529,7 @@
pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
if (!pid_list->pids) {
+ trace_parser_put(&parser);
kfree(pid_list);
return -ENOMEM;
}
@@ -738,8 +761,7 @@
{
struct trace_entry *ent = ring_buffer_event_data(event);
- tracing_generic_entry_update(ent, flags, pc);
- ent->type = type;
+ tracing_generic_entry_update(ent, type, flags, pc);
}
static __always_inline struct ring_buffer_event *
@@ -894,7 +916,7 @@
EXPORT_SYMBOL_GPL(__trace_bputs);
#ifdef CONFIG_TRACER_SNAPSHOT
-void tracing_snapshot_instance(struct trace_array *tr)
+void tracing_snapshot_instance_cond(struct trace_array *tr, void *cond_data)
{
struct tracer *tracer = tr->current_trace;
unsigned long flags;
@@ -920,10 +942,15 @@
}
local_irq_save(flags);
- update_max_tr(tr, current, smp_processor_id());
+ update_max_tr(tr, current, smp_processor_id(), cond_data);
local_irq_restore(flags);
}
+void tracing_snapshot_instance(struct trace_array *tr)
+{
+ tracing_snapshot_instance_cond(tr, NULL);
+}
+
/**
* tracing_snapshot - take a snapshot of the current buffer.
*
@@ -946,6 +973,54 @@
}
EXPORT_SYMBOL_GPL(tracing_snapshot);
+/**
+ * tracing_snapshot_cond - conditionally take a snapshot of the current buffer.
+ * @tr: The tracing instance to snapshot
+ * @cond_data: The data to be tested conditionally, and possibly saved
+ *
+ * This is the same as tracing_snapshot() except that the snapshot is
+ * conditional - the snapshot will only happen if the
+ * cond_snapshot.update() implementation receiving the cond_data
+ * returns true, which means that the trace array's cond_snapshot
+ * update() operation used the cond_data to determine whether the
+ * snapshot should be taken, and if it was, presumably saved it along
+ * with the snapshot.
+ */
+void tracing_snapshot_cond(struct trace_array *tr, void *cond_data)
+{
+ tracing_snapshot_instance_cond(tr, cond_data);
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond);
+
+/**
+ * tracing_snapshot_cond_data - get the user data associated with a snapshot
+ * @tr: The tracing instance
+ *
+ * When the user enables a conditional snapshot using
+ * tracing_snapshot_cond_enable(), the user-defined cond_data is saved
+ * with the snapshot. This accessor is used to retrieve it.
+ *
+ * Should not be called from cond_snapshot.update(), since it takes
+ * the tr->max_lock lock, which the code calling
+ * cond_snapshot.update() has already done.
+ *
+ * Returns the cond_data associated with the trace array's snapshot.
+ */
+void *tracing_cond_snapshot_data(struct trace_array *tr)
+{
+ void *cond_data = NULL;
+
+ arch_spin_lock(&tr->max_lock);
+
+ if (tr->cond_snapshot)
+ cond_data = tr->cond_snapshot->cond_data;
+
+ arch_spin_unlock(&tr->max_lock);
+
+ return cond_data;
+}
+EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data);
+
static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf,
struct trace_buffer *size_buf, int cpu_id);
static void set_buffer_entries(struct trace_buffer *buf, unsigned long val);
@@ -1025,12 +1100,111 @@
tracing_snapshot();
}
EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
+
+/**
+ * tracing_snapshot_cond_enable - enable conditional snapshot for an instance
+ * @tr: The tracing instance
+ * @cond_data: User data to associate with the snapshot
+ * @update: Implementation of the cond_snapshot update function
+ *
+ * Check whether the conditional snapshot for the given instance has
+ * already been enabled, or if the current tracer is already using a
+ * snapshot; if so, return -EBUSY, else create a cond_snapshot and
+ * save the cond_data and update function inside.
+ *
+ * Returns 0 if successful, error otherwise.
+ */
+int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data,
+ cond_update_fn_t update)
+{
+ struct cond_snapshot *cond_snapshot;
+ int ret = 0;
+
+ cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL);
+ if (!cond_snapshot)
+ return -ENOMEM;
+
+ cond_snapshot->cond_data = cond_data;
+ cond_snapshot->update = update;
+
+ mutex_lock(&trace_types_lock);
+
+ ret = tracing_alloc_snapshot_instance(tr);
+ if (ret)
+ goto fail_unlock;
+
+ if (tr->current_trace->use_max_tr) {
+ ret = -EBUSY;
+ goto fail_unlock;
+ }
+
+ /*
+ * The cond_snapshot can only change to NULL without the
+ * trace_types_lock. We don't care if we race with it going
+ * to NULL, but we want to make sure that it's not set to
+ * something other than NULL when we get here, which we can
+ * do safely with only holding the trace_types_lock and not
+ * having to take the max_lock.
+ */
+ if (tr->cond_snapshot) {
+ ret = -EBUSY;
+ goto fail_unlock;
+ }
+
+ arch_spin_lock(&tr->max_lock);
+ tr->cond_snapshot = cond_snapshot;
+ arch_spin_unlock(&tr->max_lock);
+
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+
+ fail_unlock:
+ mutex_unlock(&trace_types_lock);
+ kfree(cond_snapshot);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable);
+
+/**
+ * tracing_snapshot_cond_disable - disable conditional snapshot for an instance
+ * @tr: The tracing instance
+ *
+ * Check whether the conditional snapshot for the given instance is
+ * enabled; if so, free the cond_snapshot associated with it,
+ * otherwise return -EINVAL.
+ *
+ * Returns 0 if successful, error otherwise.
+ */
+int tracing_snapshot_cond_disable(struct trace_array *tr)
+{
+ int ret = 0;
+
+ arch_spin_lock(&tr->max_lock);
+
+ if (!tr->cond_snapshot)
+ ret = -EINVAL;
+ else {
+ kfree(tr->cond_snapshot);
+ tr->cond_snapshot = NULL;
+ }
+
+ arch_spin_unlock(&tr->max_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable);
#else
void tracing_snapshot(void)
{
WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used");
}
EXPORT_SYMBOL_GPL(tracing_snapshot);
+void tracing_snapshot_cond(struct trace_array *tr, void *cond_data)
+{
+ WARN_ONCE(1, "Snapshot feature not enabled, but internal conditional snapshot used");
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond);
int tracing_alloc_snapshot(void)
{
WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used");
@@ -1043,6 +1217,21 @@
tracing_snapshot();
}
EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
+void *tracing_cond_snapshot_data(struct trace_array *tr)
+{
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data);
+int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update)
+{
+ return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable);
+int tracing_snapshot_cond_disable(struct trace_array *tr)
+{
+ return false;
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable);
#endif /* CONFIG_TRACER_SNAPSHOT */
void tracer_tracing_off(struct trace_array *tr)
@@ -1330,7 +1519,7 @@
max_data->critical_start = data->critical_start;
max_data->critical_end = data->critical_end;
- memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
+ strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
max_data->pid = tsk->pid;
/*
* If tsk == current, then use current_uid(), as that does not use
@@ -1354,12 +1543,14 @@
* @tr: tracer
* @tsk: the task with the latency
* @cpu: The cpu that initiated the trace.
+ * @cond_data: User data associated with a conditional snapshot
*
* Flip the buffers between the @tr and the max_tr and record information
* about which task was the cause of this latency.
*/
void
-update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
+update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
+ void *cond_data)
{
if (tr->stop_count)
return;
@@ -1380,17 +1571,23 @@
else
ring_buffer_record_off(tr->max_buffer.buffer);
+#ifdef CONFIG_TRACER_SNAPSHOT
+ if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data))
+ goto out_unlock;
+#endif
swap(tr->trace_buffer.buffer, tr->max_buffer.buffer);
__update_max_tr(tr, tsk, cpu);
+
+ out_unlock:
arch_spin_unlock(&tr->max_lock);
}
/**
* update_max_tr_single - only copy one trace over, and reset the rest
- * @tr - tracer
- * @tsk - task with the latency
- * @cpu - the cpu of the buffer to copy.
+ * @tr: tracer
+ * @tsk: task with the latency
+ * @cpu: the cpu of the buffer to copy.
*
* Flip the trace of a single CPU buffer between the @tr and the max_tr.
*/
@@ -1431,7 +1628,7 @@
}
#endif /* CONFIG_TRACER_MAX_TRACE */
-static int wait_on_pipe(struct trace_iterator *iter, bool full)
+static int wait_on_pipe(struct trace_iterator *iter, int full)
{
/* Iterators are static, they should be filled or empty */
if (trace_buffer_iter(iter, iter->cpu_file))
@@ -1547,6 +1744,10 @@
pr_info("Running postponed tracer tests:\n");
list_for_each_entry_safe(p, n, &postponed_selftests, list) {
+ /* This loop can take minutes when sanitizers are enabled, so
+ * lets make sure we allow RCU processing.
+ */
+ cond_resched();
ret = run_tracer_selftest(p->type);
/* If the test fails, then warn and remove from available_tracers */
if (ret < 0) {
@@ -1584,7 +1785,7 @@
/**
* register_tracer - register a tracer with the ftrace system.
- * @type - the plugin for the tracer
+ * @type: the plugin for the tracer
*
* Register a new plugin tracer.
*/
@@ -1671,7 +1872,7 @@
return ret;
}
-void tracing_reset(struct trace_buffer *buf, int cpu)
+static void tracing_reset_cpu(struct trace_buffer *buf, int cpu)
{
struct ring_buffer *buffer = buf->buffer;
@@ -1681,7 +1882,7 @@
ring_buffer_record_disable(buffer);
/* Make sure all commits have finished */
- synchronize_sched();
+ synchronize_rcu();
ring_buffer_reset_cpu(buffer, cpu);
ring_buffer_record_enable(buffer);
@@ -1698,7 +1899,7 @@
ring_buffer_record_disable(buffer);
/* Make sure all commits have finished */
- synchronize_sched();
+ synchronize_rcu();
buf->time_start = buffer_ftrace_now(buf, buf->cpu);
@@ -1748,7 +1949,7 @@
static inline void set_cmdline(int idx, const char *cmdline)
{
- memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN);
+ strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN);
}
static int allocate_cmdlines_buffer(unsigned int val,
@@ -2047,9 +2248,9 @@
/**
* tracing_record_taskinfo - record the task info of a task
*
- * @task - task to record
- * @flags - TRACE_RECORD_CMDLINE for recording comm
- * - TRACE_RECORD_TGID for recording tgid
+ * @task: task to record
+ * @flags: TRACE_RECORD_CMDLINE for recording comm
+ * TRACE_RECORD_TGID for recording tgid
*/
void tracing_record_taskinfo(struct task_struct *task, int flags)
{
@@ -2075,10 +2276,10 @@
/**
* tracing_record_taskinfo_sched_switch - record task info for sched_switch
*
- * @prev - previous task during sched_switch
- * @next - next task during sched_switch
- * @flags - TRACE_RECORD_CMDLINE for recording comm
- * TRACE_RECORD_TGID for recording tgid
+ * @prev: previous task during sched_switch
+ * @next: next task during sched_switch
+ * @flags: TRACE_RECORD_CMDLINE for recording comm
+ * TRACE_RECORD_TGID for recording tgid
*/
void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
struct task_struct *next, int flags)
@@ -2128,13 +2329,14 @@
EXPORT_SYMBOL_GPL(trace_handle_return);
void
-tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
- int pc)
+tracing_generic_entry_update(struct trace_entry *entry, unsigned short type,
+ unsigned long flags, int pc)
{
struct task_struct *tsk = current;
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
+ entry->type = type;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -2250,7 +2452,7 @@
preempt_enable();
/* Wait for all current users to finish */
- synchronize_sched();
+ synchronize_rcu();
for_each_tracing_cpu(cpu) {
free_page((unsigned long)per_cpu(trace_buffered_event, cpu));
@@ -2452,16 +2654,16 @@
static_branch_disable(&ftrace_exports_enabled);
}
-void ftrace_exports(struct ring_buffer_event *event)
+static void ftrace_exports(struct ring_buffer_event *event)
{
struct trace_export *export;
preempt_disable_notrace();
- export = rcu_dereference_raw_notrace(ftrace_exports_list);
+ export = rcu_dereference_raw_check(ftrace_exports_list);
while (export) {
trace_process_export(export, event);
- export = rcu_dereference_raw_notrace(export->next);
+ export = rcu_dereference_raw_check(export->next);
}
preempt_enable_notrace();
@@ -2574,12 +2776,21 @@
#ifdef CONFIG_STACKTRACE
-#define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long))
+/* Allow 4 levels of nesting: normal, softirq, irq, NMI */
+#define FTRACE_KSTACK_NESTING 4
+
+#define FTRACE_KSTACK_ENTRIES (PAGE_SIZE / FTRACE_KSTACK_NESTING)
+
struct ftrace_stack {
- unsigned long calls[FTRACE_STACK_MAX_ENTRIES];
+ unsigned long calls[FTRACE_KSTACK_ENTRIES];
};
-static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack);
+
+struct ftrace_stacks {
+ struct ftrace_stack stacks[FTRACE_KSTACK_NESTING];
+};
+
+static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks);
static DEFINE_PER_CPU(int, ftrace_stack_reserve);
static void __ftrace_trace_stack(struct ring_buffer *buffer,
@@ -2588,13 +2799,10 @@
{
struct trace_event_call *call = &event_kernel_stack;
struct ring_buffer_event *event;
+ unsigned int size, nr_entries;
+ struct ftrace_stack *fstack;
struct stack_entry *entry;
- struct stack_trace trace;
- int use_stack;
- int size = FTRACE_STACK_ENTRIES;
-
- trace.nr_entries = 0;
- trace.skip = skip;
+ int stackidx;
/*
* Add one, for this function and the call to save_stack_trace()
@@ -2602,7 +2810,7 @@
*/
#ifndef CONFIG_UNWINDER_ORC
if (!regs)
- trace.skip++;
+ skip++;
#endif
/*
@@ -2613,53 +2821,40 @@
*/
preempt_disable_notrace();
- use_stack = __this_cpu_inc_return(ftrace_stack_reserve);
+ stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1;
+
+ /* This should never happen. If it does, yell once and skip */
+ if (WARN_ON_ONCE(stackidx > FTRACE_KSTACK_NESTING))
+ goto out;
+
/*
- * We don't need any atomic variables, just a barrier.
- * If an interrupt comes in, we don't care, because it would
- * have exited and put the counter back to what we want.
- * We just need a barrier to keep gcc from moving things
- * around.
+ * The above __this_cpu_inc_return() is 'atomic' cpu local. An
+ * interrupt will either see the value pre increment or post
+ * increment. If the interrupt happens pre increment it will have
+ * restored the counter when it returns. We just need a barrier to
+ * keep gcc from moving things around.
*/
barrier();
- if (use_stack == 1) {
- trace.entries = this_cpu_ptr(ftrace_stack.calls);
- trace.max_entries = FTRACE_STACK_MAX_ENTRIES;
- if (regs)
- save_stack_trace_regs(regs, &trace);
- else
- save_stack_trace(&trace);
+ fstack = this_cpu_ptr(ftrace_stacks.stacks) + stackidx;
+ size = ARRAY_SIZE(fstack->calls);
- if (trace.nr_entries > size)
- size = trace.nr_entries;
- } else
- /* From now on, use_stack is a boolean */
- use_stack = 0;
+ if (regs) {
+ nr_entries = stack_trace_save_regs(regs, fstack->calls,
+ size, skip);
+ } else {
+ nr_entries = stack_trace_save(fstack->calls, size, skip);
+ }
- size *= sizeof(unsigned long);
-
+ size = nr_entries * sizeof(unsigned long);
event = __trace_buffer_lock_reserve(buffer, TRACE_STACK,
sizeof(*entry) + size, flags, pc);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
- memset(&entry->caller, 0, size);
-
- if (use_stack)
- memcpy(&entry->caller, trace.entries,
- trace.nr_entries * sizeof(unsigned long));
- else {
- trace.max_entries = FTRACE_STACK_ENTRIES;
- trace.entries = entry->caller;
- if (regs)
- save_stack_trace_regs(regs, &trace);
- else
- save_stack_trace(&trace);
- }
-
- entry->size = trace.nr_entries;
+ memcpy(&entry->caller, fstack->calls, size);
+ entry->size = nr_entries;
if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
@@ -2727,16 +2922,17 @@
__ftrace_trace_stack(global_trace.trace_buffer.buffer,
flags, skip, preempt_count(), NULL);
}
+EXPORT_SYMBOL_GPL(trace_dump_stack);
+#ifdef CONFIG_USER_STACKTRACE_SUPPORT
static DEFINE_PER_CPU(int, user_stack_count);
-void
+static void
ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
{
struct trace_event_call *call = &event_user_stack;
struct ring_buffer_event *event;
struct userstack_entry *entry;
- struct stack_trace trace;
if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
@@ -2767,12 +2963,7 @@
entry->tgid = current->tgid;
memset(&entry->caller, 0, sizeof(entry->caller));
- trace.nr_entries = 0;
- trace.max_entries = FTRACE_STACK_ENTRIES;
- trace.skip = 0;
- trace.entries = entry->caller;
-
- save_stack_trace_user(&trace);
+ stack_trace_save_user(entry->caller, FTRACE_STACK_ENTRIES);
if (!call_filter_check_discard(call, entry, buffer, event))
__buffer_unlock_commit(buffer, event);
@@ -2781,13 +2972,12 @@
out:
preempt_enable();
}
-
-#ifdef UNUSED
-static void __trace_userstack(struct trace_array *tr, unsigned long flags)
+#else /* CONFIG_USER_STACKTRACE_SUPPORT */
+static void ftrace_trace_userstack(struct ring_buffer *buffer,
+ unsigned long flags, int pc)
{
- ftrace_trace_userstack(tr, flags, preempt_count());
}
-#endif /* UNUSED */
+#endif /* !CONFIG_USER_STACKTRACE_SUPPORT */
#endif /* CONFIG_STACKTRACE */
@@ -2877,6 +3067,7 @@
if (global_trace.trace_buffer.buffer)
tracing_start_cmdline_record();
}
+EXPORT_SYMBOL_GPL(trace_printk_init_buffers);
void trace_printk_start_comm(void)
{
@@ -2899,7 +3090,9 @@
/**
* trace_vbprintk - write binary msg to tracing buffer
- *
+ * @ip: The address of the caller
+ * @fmt: The string format to write to the buffer
+ * @args: Arguments for @fmt
*/
int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
{
@@ -3037,6 +3230,7 @@
va_end(ap);
return ret;
}
+EXPORT_SYMBOL_GPL(trace_array_printk);
__printf(3, 4)
int trace_array_printk_buf(struct ring_buffer *buffer,
@@ -3315,33 +3509,68 @@
}
static void
+get_total_entries_cpu(struct trace_buffer *buf, unsigned long *total,
+ unsigned long *entries, int cpu)
+{
+ unsigned long count;
+
+ count = ring_buffer_entries_cpu(buf->buffer, cpu);
+ /*
+ * If this buffer has skipped entries, then we hold all
+ * entries for the trace and we need to ignore the
+ * ones before the time stamp.
+ */
+ if (per_cpu_ptr(buf->data, cpu)->skipped_entries) {
+ count -= per_cpu_ptr(buf->data, cpu)->skipped_entries;
+ /* total is the same as the entries */
+ *total = count;
+ } else
+ *total = count +
+ ring_buffer_overrun_cpu(buf->buffer, cpu);
+ *entries = count;
+}
+
+static void
get_total_entries(struct trace_buffer *buf,
unsigned long *total, unsigned long *entries)
{
- unsigned long count;
+ unsigned long t, e;
int cpu;
*total = 0;
*entries = 0;
for_each_tracing_cpu(cpu) {
- count = ring_buffer_entries_cpu(buf->buffer, cpu);
- /*
- * If this buffer has skipped entries, then we hold all
- * entries for the trace and we need to ignore the
- * ones before the time stamp.
- */
- if (per_cpu_ptr(buf->data, cpu)->skipped_entries) {
- count -= per_cpu_ptr(buf->data, cpu)->skipped_entries;
- /* total is the same as the entries */
- *total += count;
- } else
- *total += count +
- ring_buffer_overrun_cpu(buf->buffer, cpu);
- *entries += count;
+ get_total_entries_cpu(buf, &t, &e, cpu);
+ *total += t;
+ *entries += e;
}
}
+unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu)
+{
+ unsigned long total, entries;
+
+ if (!tr)
+ tr = &global_trace;
+
+ get_total_entries_cpu(&tr->trace_buffer, &total, &entries, cpu);
+
+ return entries;
+}
+
+unsigned long trace_total_entries(struct trace_array *tr)
+{
+ unsigned long total, entries;
+
+ if (!tr)
+ tr = &global_trace;
+
+ get_total_entries(&tr->trace_buffer, &total, &entries);
+
+ return entries;
+}
+
static void print_lat_help_header(struct seq_file *m)
{
seq_puts(m, "# _------=> CPU# \n"
@@ -3380,23 +3609,18 @@
unsigned int flags)
{
bool tgid = flags & TRACE_ITER_RECORD_TGID;
- const char tgid_space[] = " ";
- const char space[] = " ";
+ const char *space = " ";
+ int prec = tgid ? 10 : 2;
- seq_printf(m, "# %s _-----=> irqs-off\n",
- tgid ? tgid_space : space);
- seq_printf(m, "# %s / _----=> need-resched\n",
- tgid ? tgid_space : space);
- seq_printf(m, "# %s| / _---=> hardirq/softirq\n",
- tgid ? tgid_space : space);
- seq_printf(m, "# %s|| / _--=> preempt-depth\n",
- tgid ? tgid_space : space);
- seq_printf(m, "# %s||| / delay\n",
- tgid ? tgid_space : space);
- seq_printf(m, "# TASK-PID %sCPU# |||| TIMESTAMP FUNCTION\n",
- tgid ? " TGID " : space);
- seq_printf(m, "# | | %s | |||| | |\n",
- tgid ? " | " : space);
+ print_event_info(buf, m);
+
+ seq_printf(m, "# %.*s _-----=> irqs-off\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);
+ seq_printf(m, "# %.*s||| / delay\n", prec, space);
+ seq_printf(m, "# TASK-PID %.*sCPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID ");
+ seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | ");
}
void
@@ -3901,7 +4125,8 @@
if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer,
+ cpu, GFP_KERNEL);
}
ring_buffer_read_prepare_sync();
for_each_tracing_cpu(cpu) {
@@ -3911,7 +4136,8 @@
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer,
+ cpu, GFP_KERNEL);
ring_buffer_read_prepare_sync();
ring_buffer_read_start(iter->buffer_iter[cpu]);
tracing_iter_reset(iter, cpu);
@@ -3932,8 +4158,11 @@
int tracing_open_generic(struct inode *inode, struct file *filp)
{
- if (tracing_disabled)
- return -ENODEV;
+ int ret;
+
+ ret = tracing_check_open_get_tr(NULL);
+ if (ret)
+ return ret;
filp->private_data = inode->i_private;
return 0;
@@ -3948,15 +4177,14 @@
* Open and update trace_array ref count.
* Must have the current trace_array passed to it.
*/
-static int tracing_open_generic_tr(struct inode *inode, struct file *filp)
+int tracing_open_generic_tr(struct inode *inode, struct file *filp)
{
struct trace_array *tr = inode->i_private;
+ int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
filp->private_data = inode->i_private;
@@ -4025,10 +4253,11 @@
{
struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
- int ret = 0;
+ int ret;
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
/* If this file was open for write, then erase contents */
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
@@ -4043,7 +4272,7 @@
if (cpu == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(trace_buf);
else
- tracing_reset(trace_buf, cpu);
+ tracing_reset_cpu(trace_buf, cpu);
}
if (file->f_mode & FMODE_READ) {
@@ -4144,19 +4373,30 @@
struct seq_file *m;
int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- ret = seq_open(file, &show_traces_seq_ops);
+ ret = tracing_check_open_get_tr(tr);
if (ret)
return ret;
+ ret = seq_open(file, &show_traces_seq_ops);
+ if (ret) {
+ trace_array_put(tr);
+ return ret;
+ }
+
m = file->private_data;
m->private = tr;
return 0;
}
+static int show_traces_release(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+
+ trace_array_put(tr);
+ return seq_release(inode, file);
+}
+
static ssize_t
tracing_write_stub(struct file *filp, const char __user *ubuf,
size_t count, loff_t *ppos)
@@ -4187,8 +4427,8 @@
static const struct file_operations show_traces_fops = {
.open = show_traces_open,
.read = seq_read,
- .release = seq_release,
.llseek = seq_lseek,
+ .release = show_traces_release,
};
static ssize_t
@@ -4407,13 +4647,15 @@
int neg = 0;
int ret;
size_t orig_len = strlen(option);
+ int len;
cmp = strstrip(option);
- if (strncmp(cmp, "no", 2) == 0) {
+ len = str_has_prefix(cmp, "no");
+ if (len)
neg = 1;
- cmp += 2;
- }
+
+ cmp += len;
mutex_lock(&trace_types_lock);
@@ -4487,11 +4729,9 @@
struct trace_array *tr = inode->i_private;
int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
ret = single_open(file, tracing_trace_options_show, inode->i_private);
if (ret < 0)
@@ -4518,6 +4758,7 @@
" trace_pipe\t\t- A consuming read to see the contents of the buffer\n"
" current_tracer\t- function and latency tracers\n"
" available_tracers\t- list of configured tracers for current_tracer\n"
+ " error_log\t- error log for failed commands (that support it)\n"
" buffer_size_kb\t- view and modify size of per cpu buffer\n"
" buffer_total_size_kb - view total size of all cpu buffers\n\n"
" trace_clock\t\t-change the clock used to order events\n"
@@ -4538,7 +4779,7 @@
" instances\t\t- Make sub-buffers with: mkdir instances/foo\n"
"\t\t\t Remove sub-buffer with rmdir\n"
" trace_options\t\t- Set format or modify how tracing happens\n"
- "\t\t\t Disable an option by adding a suffix 'no' to the\n"
+ "\t\t\t Disable an option by prefixing 'no' to the\n"
"\t\t\t option name\n"
" saved_cmdlines_size\t- echo command number in here to store comm-pid list\n"
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -4603,31 +4844,49 @@
"\t\t\t traces\n"
#endif
#endif /* CONFIG_STACK_TRACER */
+#ifdef CONFIG_DYNAMIC_EVENTS
+ " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n"
+ "\t\t\t Write into this file to define/undefine new trace events.\n"
+#endif
#ifdef CONFIG_KPROBE_EVENTS
- " kprobe_events\t\t- Add/remove/show the kernel dynamic events\n"
+ " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n"
"\t\t\t Write into this file to define/undefine new trace events.\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
- " uprobe_events\t\t- Add/remove/show the userspace dynamic events\n"
+ " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n"
"\t\t\t Write into this file to define/undefine new trace events.\n"
#endif
#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
"\t accepts: event-definitions (one definition per line)\n"
"\t Format: p[:[<group>/]<event>] <place> [<args>]\n"
"\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n"
+#ifdef CONFIG_HIST_TRIGGERS
+ "\t s:[synthetic/]<event> <field> [<field>]\n"
+#endif
"\t -:[<group>/]<event>\n"
#ifdef CONFIG_KPROBE_EVENTS
"\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
"place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
- "\t place: <path>:<offset>\n"
+ " place (uprobe): <path>:<offset>[(ref_ctr_offset)]\n"
#endif
"\t args: <name>=fetcharg[:type]\n"
"\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n"
- "\t $stack<index>, $stack, $retval, $comm\n"
- "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string,\n"
- "\t b<bit-width>@<bit-offset>/<container-size>\n"
+#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+ "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
+#else
+ "\t $stack<index>, $stack, $retval, $comm,\n"
+#endif
+ "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
+ "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n"
+ "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n"
+ "\t <type>\\[<array-size>\\]\n"
+#ifdef CONFIG_HIST_TRIGGERS
+ "\t field: <stype> <name>;\n"
+ "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n"
+ "\t [unsigned] char/int/long\n"
+#endif
#endif
" events/\t\t- Directory containing all trace event subsystems:\n"
" enable\t\t- Write 0/1 to enable/disable tracing of all events\n"
@@ -4680,6 +4939,7 @@
"\t [:size=#entries]\n"
"\t [:pause][:continue][:clear]\n"
"\t [:name=histname1]\n"
+ "\t [:<handler>.<action>]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -4720,8 +4980,21 @@
"\t unchanged.\n\n"
"\t The enable_hist and disable_hist triggers can be used to\n"
"\t have one event conditionally start and stop another event's\n"
- "\t already-attached hist trigger. The syntax is analagous to\n"
- "\t the enable_event and disable_event triggers.\n"
+ "\t already-attached hist trigger. The syntax is analogous to\n"
+ "\t the enable_event and disable_event triggers.\n\n"
+ "\t Hist trigger handlers and actions are executed whenever a\n"
+ "\t a histogram entry is added or updated. They take the form:\n\n"
+ "\t <handler>.<action>\n\n"
+ "\t The available handlers are:\n\n"
+ "\t onmatch(matching.event) - invoke on addition or update\n"
+ "\t onmax(var) - invoke if var exceeds current max\n"
+ "\t onchange(var) - invoke action if var changes\n\n"
+ "\t The available actions are:\n\n"
+ "\t trace(<synthetic_event>,param list) - generate synthetic event\n"
+ "\t save(field,...) - save current event fields\n"
+#ifdef CONFIG_TRACER_SNAPSHOT
+ "\t snapshot() - snapshot the trace buffer\n"
+#endif
#endif
;
@@ -4795,8 +5068,11 @@
static int tracing_saved_tgids_open(struct inode *inode, struct file *filp)
{
- if (tracing_disabled)
- return -ENODEV;
+ int ret;
+
+ ret = tracing_check_open_get_tr(NULL);
+ if (ret)
+ return ret;
return seq_open(filp, &tracing_saved_tgids_seq_ops);
}
@@ -4872,8 +5148,11 @@
static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp)
{
- if (tracing_disabled)
- return -ENODEV;
+ int ret;
+
+ ret = tracing_check_open_get_tr(NULL);
+ if (ret)
+ return ret;
return seq_open(filp, &tracing_saved_cmdlines_seq_ops);
}
@@ -5037,8 +5316,11 @@
static int tracing_eval_map_open(struct inode *inode, struct file *filp)
{
- if (tracing_disabled)
- return -ENODEV;
+ int ret;
+
+ ret = tracing_check_open_get_tr(NULL);
+ if (ret)
+ return ret;
return seq_open(filp, &tracing_eval_map_seq_ops);
}
@@ -5366,6 +5648,16 @@
if (t == tr->current_trace)
goto out;
+#ifdef CONFIG_TRACER_SNAPSHOT
+ if (t->use_max_tr) {
+ arch_spin_lock(&tr->max_lock);
+ if (tr->cond_snapshot)
+ ret = -EBUSY;
+ arch_spin_unlock(&tr->max_lock);
+ if (ret)
+ goto out;
+ }
+#endif
/* Some tracers won't work on kernel command line */
if (system_state < SYSTEM_RUNNING && t->noboot) {
pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
@@ -5392,7 +5684,7 @@
if (tr->current_trace->reset)
tr->current_trace->reset(tr);
- /* Current trace needs to be nop_trace before synchronize_sched */
+ /* Current trace needs to be nop_trace before synchronize_rcu */
tr->current_trace = &nop_trace;
#ifdef CONFIG_TRACER_MAX_TRACE
@@ -5406,7 +5698,7 @@
* The update_max_tr is called from interrupts disabled
* so a synchronized_sched() is sufficient.
*/
- synchronize_sched();
+ synchronize_rcu();
free_snapshot(tr);
}
#endif
@@ -5551,13 +5843,11 @@
{
struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
- int ret = 0;
+ int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
mutex_lock(&trace_types_lock);
@@ -5604,7 +5894,6 @@
return ret;
fail:
- kfree(iter->trace);
kfree(iter);
__trace_array_put(tr);
mutex_unlock(&trace_types_lock);
@@ -5687,7 +5976,7 @@
mutex_unlock(&iter->mutex);
- ret = wait_on_pipe(iter, false);
+ ret = wait_on_pipe(iter, 0);
mutex_lock(&iter->mutex);
@@ -5747,6 +6036,7 @@
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
cpumask_clear(iter->started);
+ trace_seq_init(&iter->seq);
iter->pos = -1;
trace_event_read_lock();
@@ -5803,7 +6093,6 @@
}
static const struct pipe_buf_operations tracing_pipe_buf_ops = {
- .can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = generic_pipe_buf_release,
.steal = generic_pipe_buf_steal,
@@ -6083,13 +6372,13 @@
struct ring_buffer *buffer;
struct print_entry *entry;
unsigned long irq_flags;
- const char faulted[] = "<faulted>";
ssize_t written;
int size;
int len;
/* Used in tracing_mark_raw_write() as well */
-#define FAULTED_SIZE (sizeof(faulted) - 1) /* '\0' is already accounted for */
+#define FAULTED_STR "<faulted>"
+#define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */
if (tracing_disabled)
return -EINVAL;
@@ -6121,7 +6410,7 @@
len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt);
if (len) {
- memcpy(&entry->buf, faulted, FAULTED_SIZE);
+ memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE);
cnt = FAULTED_SIZE;
written = -EFAULT;
} else
@@ -6162,7 +6451,6 @@
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct raw_data_entry *entry;
- const char faulted[] = "<faulted>";
unsigned long irq_flags;
ssize_t written;
int size;
@@ -6202,7 +6490,7 @@
len = __copy_from_user_inatomic(&entry->id, ubuf, cnt);
if (len) {
entry->id = -1;
- memcpy(&entry->buf, faulted, FAULTED_SIZE);
+ memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE);
written = -EFAULT;
} else
written = cnt;
@@ -6297,11 +6585,9 @@
struct trace_array *tr = inode->i_private;
int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr))
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
ret = single_open(file, tracing_clock_show, inode->i_private);
if (ret < 0)
@@ -6331,11 +6617,9 @@
struct trace_array *tr = inode->i_private;
int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr))
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private);
if (ret < 0)
@@ -6388,10 +6672,11 @@
struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
struct seq_file *m;
- int ret = 0;
+ int ret;
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
if (file->f_mode & FMODE_READ) {
iter = __tracing_open(inode, file, true);
@@ -6448,6 +6733,13 @@
goto out;
}
+ arch_spin_lock(&tr->max_lock);
+ if (tr->cond_snapshot)
+ ret = -EBUSY;
+ arch_spin_unlock(&tr->max_lock);
+ if (ret)
+ goto out;
+
switch (val) {
case 0:
if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
@@ -6465,15 +6757,17 @@
break;
}
#endif
- if (!tr->allocated_snapshot) {
+ if (tr->allocated_snapshot)
+ ret = resize_buffer_duplicate_size(&tr->max_buffer,
+ &tr->trace_buffer, iter->cpu_file);
+ else
ret = tracing_alloc_snapshot_instance(tr);
- if (ret < 0)
- break;
- }
+ if (ret < 0)
+ break;
local_irq_disable();
/* Now, we're going to swap */
if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
- update_max_tr(tr, current, smp_processor_id());
+ update_max_tr(tr, current, smp_processor_id(), NULL);
else
update_max_tr_single(tr, current, iter->cpu_file);
local_irq_enable();
@@ -6483,7 +6777,7 @@
if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(&tr->max_buffer);
else
- tracing_reset(&tr->max_buffer, iter->cpu_file);
+ tracing_reset_cpu(&tr->max_buffer, iter->cpu_file);
}
break;
}
@@ -6527,6 +6821,7 @@
struct ftrace_buffer_info *info;
int ret;
+ /* The following checks for tracefs lockdown */
ret = tracing_buffers_open(inode, filp);
if (ret < 0)
return ret;
@@ -6648,17 +6943,260 @@
#endif /* CONFIG_TRACER_SNAPSHOT */
+#define TRACING_LOG_ERRS_MAX 8
+#define TRACING_LOG_LOC_MAX 128
+
+#define CMD_PREFIX " Command: "
+
+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 */
+ u64 ts;
+};
+
+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 */
+};
+
+static DEFINE_MUTEX(tracing_err_log_lock);
+
+static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr)
+{
+ 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++;
+
+ return err;
+ }
+
+ err = list_first_entry(&tr->err_log, struct tracing_log_err, list);
+ list_del(&err->list);
+
+ return err;
+}
+
+/**
+ * err_pos - find the position of a string within a command for error careting
+ * @cmd: The tracing command that caused the error
+ * @str: The string to position the caret at within @cmd
+ *
+ * Finds the position of the first occurence of @str within @cmd. The
+ * return value can be passed to tracing_log_err() for caret placement
+ * within @cmd.
+ *
+ * Returns the index within @cmd of the first occurence of @str or 0
+ * if @str was not found.
+ */
+unsigned int err_pos(char *cmd, const char *str)
+{
+ char *found;
+
+ if (WARN_ON(!strlen(cmd)))
+ return 0;
+
+ found = strstr(cmd, str);
+ if (found)
+ return found - cmd;
+
+ return 0;
+}
+
+/**
+ * tracing_log_err - write an error to the tracing error log
+ * @tr: The associated trace array for the error (NULL for top level array)
+ * @loc: A string describing where the error occurred
+ * @cmd: The tracing command that caused the error
+ * @errs: The array of loc-specific static error strings
+ * @type: The index into errs[], which produces the specific static err string
+ * @pos: The position the caret should be placed in the cmd
+ *
+ * Writes an error into tracing/error_log of the form:
+ *
+ * <loc>: error: <text>
+ * Command: <cmd>
+ * ^
+ *
+ * tracing/error_log is a small log file containing the last
+ * TRACING_LOG_ERRS_MAX errors (8). Memory for errors isn't allocated
+ * unless there has been a tracing error, and the error log can be
+ * cleared and have its memory freed by writing the empty string in
+ * truncation mode to it i.e. echo > tracing/error_log.
+ *
+ * NOTE: the @errs array along with the @type param are used to
+ * produce a static error string - this string is not copied and saved
+ * when the error is logged - only a pointer to it is saved. See
+ * existing callers for examples of how static strings are typically
+ * defined for use with tracing_log_err().
+ */
+void tracing_log_err(struct trace_array *tr,
+ const char *loc, const char *cmd,
+ const char **errs, u8 type, u8 pos)
+{
+ struct tracing_log_err *err;
+
+ if (!tr)
+ tr = &global_trace;
+
+ mutex_lock(&tracing_err_log_lock);
+ err = get_tracing_log_err(tr);
+ 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);
+
+ err->info.errs = errs;
+ err->info.type = type;
+ err->info.pos = pos;
+ err->info.ts = local_clock();
+
+ list_add_tail(&err->list, &tr->err_log);
+ mutex_unlock(&tracing_err_log_lock);
+}
+
+static void clear_tracing_err_log(struct trace_array *tr)
+{
+ struct tracing_log_err *err, *next;
+
+ mutex_lock(&tracing_err_log_lock);
+ list_for_each_entry_safe(err, next, &tr->err_log, list) {
+ list_del(&err->list);
+ kfree(err);
+ }
+
+ tr->n_err_log_entries = 0;
+ mutex_unlock(&tracing_err_log_lock);
+}
+
+static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos)
+{
+ struct trace_array *tr = m->private;
+
+ mutex_lock(&tracing_err_log_lock);
+
+ return seq_list_start(&tr->err_log, *pos);
+}
+
+static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_array *tr = m->private;
+
+ return seq_list_next(v, &tr->err_log, pos);
+}
+
+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)
+{
+ u8 i;
+
+ for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++)
+ seq_putc(m, ' ');
+ for (i = 0; i < pos; i++)
+ seq_putc(m, ' ');
+ seq_puts(m, "^\n");
+}
+
+static int tracing_err_log_seq_show(struct seq_file *m, void *v)
+{
+ struct tracing_log_err *err = v;
+
+ if (err) {
+ const char *err_text = err->info.errs[err->info.type];
+ u64 sec = err->info.ts;
+ u32 nsec;
+
+ nsec = do_div(sec, NSEC_PER_SEC);
+ seq_printf(m, "[%5llu.%06u] %s%s", sec, nsec / 1000,
+ err->loc, err_text);
+ seq_printf(m, "%s", err->cmd);
+ tracing_err_log_show_pos(m, err->info.pos);
+ }
+
+ return 0;
+}
+
+static const struct seq_operations tracing_err_log_seq_ops = {
+ .start = tracing_err_log_seq_start,
+ .next = tracing_err_log_seq_next,
+ .stop = tracing_err_log_seq_stop,
+ .show = tracing_err_log_seq_show
+};
+
+static int tracing_err_log_open(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+ int ret = 0;
+
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
+
+ /* If this file was opened for write, then erase contents */
+ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC))
+ clear_tracing_err_log(tr);
+
+ if (file->f_mode & FMODE_READ) {
+ ret = seq_open(file, &tracing_err_log_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = tr;
+ } else {
+ trace_array_put(tr);
+ }
+ }
+ return ret;
+}
+
+static ssize_t tracing_err_log_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ return count;
+}
+
+static int tracing_err_log_release(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+
+ trace_array_put(tr);
+
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
+
+ return 0;
+}
+
+static const struct file_operations tracing_err_log_fops = {
+ .open = tracing_err_log_open,
+ .write = tracing_err_log_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_err_log_release,
+};
+
static int tracing_buffers_open(struct inode *inode, struct file *filp)
{
struct trace_array *tr = inode->i_private;
struct ftrace_buffer_info *info;
int ret;
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
@@ -6745,7 +7283,7 @@
if ((filp->f_flags & O_NONBLOCK))
return -EAGAIN;
- ret = wait_on_pipe(iter, false);
+ ret = wait_on_pipe(iter, 0);
if (ret)
return ret;
@@ -6797,36 +7335,43 @@
struct ring_buffer *buffer;
void *page;
int cpu;
- int ref;
+ refcount_t refcount;
};
+static void buffer_ref_release(struct buffer_ref *ref)
+{
+ if (!refcount_dec_and_test(&ref->refcount))
+ return;
+ ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
+ kfree(ref);
+}
+
static void buffer_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct buffer_ref *ref = (struct buffer_ref *)buf->private;
- if (--ref->ref)
- return;
-
- ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
- kfree(ref);
+ buffer_ref_release(ref);
buf->private = 0;
}
-static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
+static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct buffer_ref *ref = (struct buffer_ref *)buf->private;
- ref->ref++;
+ if (refcount_read(&ref->refcount) > INT_MAX/2)
+ return false;
+
+ refcount_inc(&ref->refcount);
+ return true;
}
/* Pipe buffer operations for a buffer. */
static const struct pipe_buf_operations buffer_pipe_buf_ops = {
- .can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = buffer_pipe_buf_release,
- .steal = generic_pipe_buf_steal,
+ .steal = generic_pipe_buf_nosteal,
.get = buffer_pipe_buf_get,
};
@@ -6839,11 +7384,7 @@
struct buffer_ref *ref =
(struct buffer_ref *)spd->partial[i].private;
- if (--ref->ref)
- return;
-
- ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
- kfree(ref);
+ buffer_ref_release(ref);
spd->partial[i].private = 0;
}
@@ -6898,7 +7439,7 @@
break;
}
- ref->ref = 1;
+ refcount_set(&ref->refcount, 1);
ref->buffer = iter->trace_buffer->buffer;
ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
if (IS_ERR(ref->page)) {
@@ -6942,7 +7483,7 @@
if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK))
goto out;
- ret = wait_on_pipe(iter, true);
+ ret = wait_on_pipe(iter, iter->tr->buffer_percent);
if (ret)
goto out;
@@ -7656,7 +8197,54 @@
.llseek = default_llseek,
};
-struct dentry *trace_instance_dir;
+static ssize_t
+buffer_percent_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = tr->buffer_percent;
+ r = sprintf(buf, "%d\n", r);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+buffer_percent_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ if (val > 100)
+ return -EINVAL;
+
+ if (!val)
+ val = 1;
+
+ tr->buffer_percent = val;
+
+ (*ppos)++;
+
+ return cnt;
+}
+
+static const struct file_operations buffer_percent_fops = {
+ .open = tracing_open_generic_tr,
+ .read = buffer_percent_read,
+ .write = buffer_percent_write,
+ .release = tracing_release_generic_tr,
+ .llseek = default_llseek,
+};
+
+static struct dentry *trace_instance_dir;
static void
init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer);
@@ -7763,7 +8351,7 @@
mutex_unlock(&trace_types_lock);
}
-static int instance_mkdir(const char *name)
+struct trace_array *trace_array_create(const char *name)
{
struct trace_array *tr;
int ret;
@@ -7802,6 +8390,7 @@
INIT_LIST_HEAD(&tr->systems);
INIT_LIST_HEAD(&tr->events);
INIT_LIST_HEAD(&tr->hist_vars);
+ INIT_LIST_HEAD(&tr->err_log);
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
@@ -7827,7 +8416,7 @@
mutex_unlock(&trace_types_lock);
mutex_unlock(&event_mutex);
- return 0;
+ return tr;
out_free_tr:
free_trace_buffers(tr);
@@ -7839,33 +8428,21 @@
mutex_unlock(&trace_types_lock);
mutex_unlock(&event_mutex);
- return ret;
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(trace_array_create);
+static int instance_mkdir(const char *name)
+{
+ return PTR_ERR_OR_ZERO(trace_array_create(name));
}
-static int instance_rmdir(const char *name)
+static int __remove_instance(struct trace_array *tr)
{
- struct trace_array *tr;
- int found = 0;
- int ret;
int i;
- mutex_lock(&event_mutex);
- mutex_lock(&trace_types_lock);
-
- ret = -ENODEV;
- list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr->name && strcmp(tr->name, name) == 0) {
- found = 1;
- break;
- }
- }
- if (!found)
- goto out_unlock;
-
- ret = -EBUSY;
if (tr->ref || (tr->current_trace && tr->current_trace->ref))
- goto out_unlock;
+ return -EBUSY;
list_del(&tr->list);
@@ -7891,10 +8468,46 @@
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
+ tr = NULL;
- ret = 0;
+ return 0;
+}
- out_unlock:
+int trace_array_destroy(struct trace_array *tr)
+{
+ int ret;
+
+ if (!tr)
+ return -EINVAL;
+
+ mutex_lock(&event_mutex);
+ mutex_lock(&trace_types_lock);
+
+ ret = __remove_instance(tr);
+
+ mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(trace_array_destroy);
+
+static int instance_rmdir(const char *name)
+{
+ struct trace_array *tr;
+ int ret;
+
+ mutex_lock(&event_mutex);
+ mutex_lock(&trace_types_lock);
+
+ ret = -ENODEV;
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (tr->name && strcmp(tr->name, name) == 0) {
+ ret = __remove_instance(tr);
+ break;
+ }
+ }
+
mutex_unlock(&trace_types_lock);
mutex_unlock(&event_mutex);
@@ -7964,6 +8577,11 @@
trace_create_file("timestamp_mode", 0444, d_tracer, tr,
&trace_time_stamp_mode_fops);
+ tr->buffer_percent = 50;
+
+ trace_create_file("buffer_percent", 0444, d_tracer,
+ tr, &buffer_percent_fops);
+
create_trace_options_dir(tr);
#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
@@ -7979,6 +8597,9 @@
tr, &snapshot_fops);
#endif
+ trace_create_file("error_log", 0644, d_tracer,
+ tr, &tracing_err_log_fops);
+
for_each_tracing_cpu(cpu)
tracing_init_tracefs_percpu(tr, cpu);
@@ -8035,10 +8656,6 @@
*/
tr->dir = debugfs_create_automount("tracing", NULL,
trace_automount, NULL);
- if (!tr->dir) {
- pr_warn_once("Could not create debugfs directory 'tracing'\n");
- return ERR_PTR(-ENOMEM);
- }
return NULL;
}
@@ -8341,12 +8958,8 @@
cnt++;
- /* reset all but tr, trace, and overruns */
- memset(&iter.seq, 0,
- sizeof(struct trace_iterator) -
- offsetof(struct trace_iterator, seq));
+ trace_iterator_reset(&iter);
iter.iter_flags |= TRACE_FILE_LAT_FMT;
- iter.pos = -1;
if (trace_find_next_entry_inc(&iter) != NULL) {
int ret;
@@ -8564,6 +9177,7 @@
INIT_LIST_HEAD(&global_trace.systems);
INIT_LIST_HEAD(&global_trace.events);
INIT_LIST_HEAD(&global_trace.hist_vars);
+ INIT_LIST_HEAD(&global_trace.err_log);
list_add(&global_trace.list, &ftrace_trace_arrays);
apply_trace_boot_options();