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-rw-r--r--kernel/trace/ftrace.c54
-rw-r--r--kernel/trace/ring_buffer.c81
-rw-r--r--kernel/trace/trace.c33
-rw-r--r--kernel/trace/trace_syscalls.c8
4 files changed, 110 insertions, 66 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fb186b9ddf51..31c90fec4158 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1925,8 +1925,16 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
* when we are adding another op to the rec or removing the
* current one. Thus, if the op is being added, we can
* ignore it because it hasn't attached itself to the rec
- * yet. That means we just need to find the op that has a
- * trampoline and is not beeing added.
+ * yet.
+ *
+ * If an ops is being modified (hooking to different functions)
+ * then we don't care about the new functions that are being
+ * added, just the old ones (that are probably being removed).
+ *
+ * If we are adding an ops to a function that already is using
+ * a trampoline, it needs to be removed (trampolines are only
+ * for single ops connected), then an ops that is not being
+ * modified also needs to be checked.
*/
do_for_each_ftrace_op(op, ftrace_ops_list) {
@@ -1940,17 +1948,23 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
if (op->flags & FTRACE_OPS_FL_ADDING)
continue;
+
/*
- * If the ops is not being added and has a trampoline,
- * then it must be the one that we want!
+ * If the ops is being modified and is in the old
+ * hash, then it is probably being removed from this
+ * function.
*/
- if (hash_contains_ip(ip, op->func_hash))
- return op;
-
- /* If the ops is being modified, it may be in the old hash. */
if ((op->flags & FTRACE_OPS_FL_MODIFYING) &&
hash_contains_ip(ip, &op->old_hash))
return op;
+ /*
+ * If the ops is not being added or modified, and it's
+ * in its normal filter hash, then this must be the one
+ * we want!
+ */
+ if (!(op->flags & FTRACE_OPS_FL_MODIFYING) &&
+ hash_contains_ip(ip, op->func_hash))
+ return op;
} while_for_each_ftrace_op(op);
@@ -2293,10 +2307,13 @@ static void ftrace_run_update_code(int command)
FTRACE_WARN_ON(ret);
}
-static void ftrace_run_modify_code(struct ftrace_ops *ops, int command)
+static void ftrace_run_modify_code(struct ftrace_ops *ops, int command,
+ struct ftrace_hash *old_hash)
{
ops->flags |= FTRACE_OPS_FL_MODIFYING;
+ ops->old_hash.filter_hash = old_hash;
ftrace_run_update_code(command);
+ ops->old_hash.filter_hash = NULL;
ops->flags &= ~FTRACE_OPS_FL_MODIFYING;
}
@@ -3340,7 +3357,7 @@ static struct ftrace_ops trace_probe_ops __read_mostly =
static int ftrace_probe_registered;
-static void __enable_ftrace_function_probe(void)
+static void __enable_ftrace_function_probe(struct ftrace_hash *old_hash)
{
int ret;
int i;
@@ -3348,7 +3365,8 @@ static void __enable_ftrace_function_probe(void)
if (ftrace_probe_registered) {
/* still need to update the function call sites */
if (ftrace_enabled)
- ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS);
+ ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS,
+ old_hash);
return;
}
@@ -3477,13 +3495,14 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
} while_for_each_ftrace_rec();
ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+
+ __enable_ftrace_function_probe(old_hash);
+
if (!ret)
free_ftrace_hash_rcu(old_hash);
else
count = ret;
- __enable_ftrace_function_probe();
-
out_unlock:
mutex_unlock(&ftrace_lock);
out:
@@ -3764,10 +3783,11 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
return add_hash_entry(hash, ip);
}
-static void ftrace_ops_update_code(struct ftrace_ops *ops)
+static void ftrace_ops_update_code(struct ftrace_ops *ops,
+ struct ftrace_hash *old_hash)
{
if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled)
- ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS);
+ ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
}
static int
@@ -3813,7 +3833,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
old_hash = *orig_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
if (!ret) {
- ftrace_ops_update_code(ops);
+ ftrace_ops_update_code(ops, old_hash);
free_ftrace_hash_rcu(old_hash);
}
mutex_unlock(&ftrace_lock);
@@ -4058,7 +4078,7 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
if (!ret) {
- ftrace_ops_update_code(iter->ops);
+ ftrace_ops_update_code(iter->ops, old_hash);
free_ftrace_hash_rcu(old_hash);
}
mutex_unlock(&ftrace_lock);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 2d75c94ae87d..a56e07c8d15b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -538,16 +538,18 @@ 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
@@ -564,36 +566,61 @@ 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 459a7b1251e5..426962b04183 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1076,13 +1076,14 @@ 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
@@ -4434,15 +4435,12 @@ 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;
@@ -5372,16 +5370,12 @@ 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;
@@ -5500,7 +5494,7 @@ 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);
@@ -5538,13 +5532,16 @@ 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;
}
@@ -5582,19 +5579,19 @@ 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;
}
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 4dc8b79c5f75..29228c4d5696 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -313,7 +313,7 @@ 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) */
@@ -360,7 +360,7 @@ 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()) */
@@ -567,7 +567,7 @@ 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;
@@ -641,7 +641,7 @@ 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 2024-12-02 20:01:18 +0000