Fix: lttng_this_cpu_ptr wrapper for kernel 3.19+

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

diff --git a/lib/ringbuffer/frontend_api.h b/lib/ringbuffer/frontend_api.h
index 13975602380bf02e82979c071969be0eaa56612a..b622bd7e865cae4079a4a91c2bab87eed34ebb32 100644 (file)
--- a/lib/ringbuffer/frontend_api.h
+++ b/lib/ringbuffer/frontend_api.h
@@ -30,6 +30,7 @@
  */
 
 #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();
 }
 
@@ -125,6 +126,14 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config,
         * boundary. It's safe to write.
         */
        *o_end = *o_begin + ctx->slot_size;
+
+       if (unlikely((subbuf_offset(*o_end, chan)) == 0))
+               /*
+                * The offset_end will fall at the very beginning of the next
+                * subbuffer.
+                */
+               return 1;
+
        return 0;
 }
 
@@ -284,14 +293,13 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config,
        commit_count = v_read(config, &buf->commit_hot[endidx].cc);
 
        lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1,
-                                     commit_count, endidx);
+                                     commit_count, endidx, ctx->tsc);
        /*
         * Update used size at each commit. It's needed only for extracting
         * ring_buffer buffers from vmcore, after crash.
         */
        lib_ring_buffer_write_commit_counter(config, buf, chan, endidx,
-                                            ctx->buf_offset, commit_count,
-                                        ctx->slot_size);
+                       offset_end, commit_count);
 }
 
 /**