Performance: Mark channel and buffer event disabled check unlikely

[lttng-modules.git] / lib / ringbuffer / frontend_api.h

diff --git a/lib/ringbuffer/frontend_api.h b/lib/ringbuffer/frontend_api.h
index ff6abce93d684a86e48066ed7fc537a2516fe9b4..517af6350b7c620a881dddf13401b4979969a793 100644 (file)
--- a/lib/ringbuffer/frontend_api.h
+++ b/lib/ringbuffer/frontend_api.h
@@ -29,7 +29,8 @@
  * See linux/ringbuffer/frontend.h for channel allocation and read-side API.
  */
 
-#include "../../wrapper/ringbuffer/frontend.h"
+#include <wrapper/ringbuffer/frontend.h>
+#include <wrapper/percpu-defs.h>
 #include <linux/errno.h>
 #include <linux/prefetch.h>
 
@@ -73,7 +74,7 @@ static inline
 void lib_ring_buffer_put_cpu(const struct lib_ring_buffer_config *config)
 {
        barrier();
-       __get_cpu_var(lib_ring_buffer_nesting)--;
+       (*lttng_this_cpu_ptr(&lib_ring_buffer_nesting))--;
        rcu_read_unlock_sched_notrace();
 }
 
@@ -161,14 +162,14 @@ int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config,
        unsigned long o_begin, o_end, o_old;
        size_t before_hdr_pad = 0;
 
-       if (atomic_read(&chan->record_disabled))
+       if (unlikely(atomic_read(&chan->record_disabled)))
                return -EAGAIN;
 
        if (config->alloc == RING_BUFFER_ALLOC_PER_CPU)
                buf = per_cpu_ptr(chan->backend.buf, ctx->cpu);
        else
                buf = chan->backend.buf;
-       if (atomic_read(&buf->record_disabled))
+       if (unlikely(atomic_read(&buf->record_disabled)))
                return -EAGAIN;
        ctx->buf = buf;