diff options
| -rw-r--r-- | kernel/trace/ring_buffer.c | 37 |
1 files changed, 19 insertions, 18 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 53ffcf53fcd7..47400300a63f 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -467,6 +467,7 @@ struct ring_buffer_per_cpu { arch_spinlock_t lock; struct lock_class_key lock_key; unsigned int nr_pages; + unsigned int current_context; struct list_head *pages; struct buffer_page *head_page; /* read from head */ struct buffer_page *tail_page; /* write to tail */ @@ -2680,11 +2681,11 @@ rb_reserve_next_event(struct ring_buffer *buffer, * just so happens that it is the same bit corresponding to * the current context. */ -static DEFINE_PER_CPU(unsigned int, current_context); -static __always_inline int trace_recursive_lock(void) +static __always_inline int +trace_recursive_lock(struct ring_buffer_per_cpu *cpu_buffer) { - unsigned int val = __this_cpu_read(current_context); + unsigned int val = cpu_buffer->current_context; int bit; if (in_interrupt()) { @@ -2701,20 +2702,21 @@ static __always_inline int trace_recursive_lock(void) return 1; val |= (1 << bit); - __this_cpu_write(current_context, val); + cpu_buffer->current_context = val; return 0; } -static __always_inline void trace_recursive_unlock(void) +static __always_inline void +trace_recursive_unlock(struct ring_buffer_per_cpu *cpu_buffer) { - __this_cpu_and(current_context, __this_cpu_read(current_context) - 1); + cpu_buffer->current_context &= cpu_buffer->current_context - 1; } #else -#define trace_recursive_lock() (0) -#define trace_recursive_unlock() do { } while (0) +#define trace_recursive_lock(cpu_buffer) (0) +#define trace_recursive_unlock(cpu_buffer) do { } while (0) #endif @@ -2747,10 +2749,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length) preempt_disable_notrace(); if (unlikely(atomic_read(&buffer->record_disabled))) - goto out_nocheck; - - if (unlikely(trace_recursive_lock())) - goto out_nocheck; + goto out; cpu = raw_smp_processor_id(); @@ -2765,16 +2764,18 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length) if (unlikely(length > BUF_MAX_DATA_SIZE)) goto out; + if (unlikely(trace_recursive_lock(cpu_buffer))) + goto out; + event = rb_reserve_next_event(buffer, cpu_buffer, length); if (!event) - goto out; + goto out_unlock; return event; + out_unlock: + trace_recursive_unlock(cpu_buffer); out: - trace_recursive_unlock(); - - out_nocheck: preempt_enable_notrace(); return NULL; } @@ -2864,7 +2865,7 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer, rb_wakeups(buffer, cpu_buffer); - trace_recursive_unlock(); + trace_recursive_unlock(cpu_buffer); preempt_enable_notrace(); @@ -2975,7 +2976,7 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer, out: rb_end_commit(cpu_buffer); - trace_recursive_unlock(); + trace_recursive_unlock(cpu_buffer); preempt_enable_notrace(); |