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-rw-r--r--kernel/trace/ring_buffer.c81
-rw-r--r--kernel/trace/trace.c37
-rw-r--r--kernel/trace/trace_events.c2
-rw-r--r--kernel/trace/trace_syscalls.c8
4 files changed, 76 insertions, 52 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index a28bdd17c853..7a4104cb95cb 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -535,16 +535,18 @@ static void rb_wake_up_waiters(struct irq_work *work)
* ring_buffer_wait - wait for input to the ring buffer
* @buffer: buffer to wait on
* @cpu: the cpu buffer to wait on
+ * @full: wait until a full page is available, if @cpu != RING_BUFFER_ALL_CPUS
*
* If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon
* as data is added to any of the @buffer's cpu buffers. Otherwise
* it will wait for data to be added to a specific cpu buffer.
*/
-int ring_buffer_wait(struct ring_buffer *buffer, int cpu)
+int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
{
- struct ring_buffer_per_cpu *cpu_buffer;
+ struct ring_buffer_per_cpu *uninitialized_var(cpu_buffer);
DEFINE_WAIT(wait);
struct rb_irq_work *work;
+ int ret = 0;
/*
* Depending on what the caller is waiting for, either any
@@ -561,36 +563,61 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu)
}
- prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
+ while (true) {
+ prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
- /*
- * The events can happen in critical sections where
- * checking a work queue can cause deadlocks.
- * After adding a task to the queue, this flag is set
- * only to notify events to try to wake up the queue
- * using irq_work.
- *
- * We don't clear it even if the buffer is no longer
- * empty. The flag only causes the next event to run
- * irq_work to do the work queue wake up. The worse
- * that can happen if we race with !trace_empty() is that
- * an event will cause an irq_work to try to wake up
- * an empty queue.
- *
- * There's no reason to protect this flag either, as
- * the work queue and irq_work logic will do the necessary
- * synchronization for the wake ups. The only thing
- * that is necessary is that the wake up happens after
- * a task has been queued. It's OK for spurious wake ups.
- */
- work->waiters_pending = true;
+ /*
+ * The events can happen in critical sections where
+ * checking a work queue can cause deadlocks.
+ * After adding a task to the queue, this flag is set
+ * only to notify events to try to wake up the queue
+ * using irq_work.
+ *
+ * We don't clear it even if the buffer is no longer
+ * empty. The flag only causes the next event to run
+ * irq_work to do the work queue wake up. The worse
+ * that can happen if we race with !trace_empty() is that
+ * an event will cause an irq_work to try to wake up
+ * an empty queue.
+ *
+ * There's no reason to protect this flag either, as
+ * the work queue and irq_work logic will do the necessary
+ * synchronization for the wake ups. The only thing
+ * that is necessary is that the wake up happens after
+ * a task has been queued. It's OK for spurious wake ups.
+ */
+ work->waiters_pending = true;
+
+ if (signal_pending(current)) {
+ ret = -EINTR;
+ break;
+ }
+
+ if (cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer))
+ break;
+
+ if (cpu != RING_BUFFER_ALL_CPUS &&
+ !ring_buffer_empty_cpu(buffer, cpu)) {
+ unsigned long flags;
+ bool pagebusy;
+
+ if (!full)
+ break;
+
+ raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
+ pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page;
+ raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
+
+ if (!pagebusy)
+ break;
+ }
- if ((cpu == RING_BUFFER_ALL_CPUS && ring_buffer_empty(buffer)) ||
- (cpu != RING_BUFFER_ALL_CPUS && ring_buffer_empty_cpu(buffer, cpu)))
schedule();
+ }
finish_wait(&work->waiters, &wait);
- return 0;
+
+ return ret;
}
/**
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4ceb2546c7ef..ce11fa50a2f0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1077,13 +1077,14 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
}
#endif /* CONFIG_TRACER_MAX_TRACE */
-static int wait_on_pipe(struct trace_iterator *iter)
+static int wait_on_pipe(struct trace_iterator *iter, bool full)
{
/* Iterators are static, they should be filled or empty */
if (trace_buffer_iter(iter, iter->cpu_file))
return 0;
- return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file);
+ return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file,
+ full);
}
#ifdef CONFIG_FTRACE_STARTUP_TEST
@@ -4433,15 +4434,12 @@ static int tracing_wait_pipe(struct file *filp)
mutex_unlock(&iter->mutex);
- ret = wait_on_pipe(iter);
+ ret = wait_on_pipe(iter, false);
mutex_lock(&iter->mutex);
if (ret)
return ret;
-
- if (signal_pending(current))
- return -EINTR;
}
return 1;
@@ -5371,16 +5369,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
goto out_unlock;
}
mutex_unlock(&trace_types_lock);
- ret = wait_on_pipe(iter);
+ ret = wait_on_pipe(iter, false);
mutex_lock(&trace_types_lock);
if (ret) {
size = ret;
goto out_unlock;
}
- if (signal_pending(current)) {
- size = -EINTR;
- goto out_unlock;
- }
goto again;
}
size = 0;
@@ -5499,7 +5493,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
};
struct buffer_ref *ref;
int entries, size, i;
- ssize_t ret;
+ ssize_t ret = 0;
mutex_lock(&trace_types_lock);
@@ -5537,13 +5531,16 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
int r;
ref = kzalloc(sizeof(*ref), GFP_KERNEL);
- if (!ref)
+ if (!ref) {
+ ret = -ENOMEM;
break;
+ }
ref->ref = 1;
ref->buffer = iter->trace_buffer->buffer;
ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
if (!ref->page) {
+ ret = -ENOMEM;
kfree(ref);
break;
}
@@ -5581,19 +5578,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
/* did we read anything? */
if (!spd.nr_pages) {
+ if (ret)
+ goto out;
+
if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) {
ret = -EAGAIN;
goto out;
}
mutex_unlock(&trace_types_lock);
- ret = wait_on_pipe(iter);
+ ret = wait_on_pipe(iter, true);
mutex_lock(&trace_types_lock);
if (ret)
goto out;
- if (signal_pending(current)) {
- ret = -EINTR;
- goto out;
- }
+
goto again;
}
@@ -6419,7 +6416,7 @@ static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t m
int ret;
/* Paranoid: Make sure the parent is the "instances" directory */
- parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+ parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
if (WARN_ON_ONCE(parent != trace_instance_dir))
return -ENOENT;
@@ -6446,7 +6443,7 @@ static int instance_rmdir(struct inode *inode, struct dentry *dentry)
int ret;
/* Paranoid: Make sure the parent is the "instances" directory */
- parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+ parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias);
if (WARN_ON_ONCE(parent != trace_instance_dir))
return -ENOENT;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f9d0cbe014b7..139716bcef7a 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -461,7 +461,7 @@ static void remove_event_file_dir(struct ftrace_event_file *file)
if (dir) {
spin_lock(&dir->d_lock); /* probably unneeded */
- list_for_each_entry(child, &dir->d_subdirs, d_u.d_child) {
+ list_for_each_entry(child, &dir->d_subdirs, d_child) {
if (child->d_inode) /* probably unneeded */
child->d_inode->i_private = NULL;
}
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index a72f3d8d813e..dfe00a4f3f3e 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -304,7 +304,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
int size;
syscall_nr = trace_get_syscall_nr(current, regs);
- if (syscall_nr < 0)
+ if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
return;
/* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */
@@ -351,7 +351,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
int syscall_nr;
syscall_nr = trace_get_syscall_nr(current, regs);
- if (syscall_nr < 0)
+ if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
return;
/* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */
@@ -558,7 +558,7 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
int size;
syscall_nr = trace_get_syscall_nr(current, regs);
- if (syscall_nr < 0)
+ if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
return;
if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
return;
@@ -632,7 +632,7 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
int size;
syscall_nr = trace_get_syscall_nr(current, regs);
- if (syscall_nr < 0)
+ if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
return;
if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
return;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 17:11:51 +0100