Fix: fixup ringbuffer tls at constructor by forcing read

[lttng-ust.git] / libringbuffer / ring_buffer_frontend.c

diff --git a/libringbuffer/ring_buffer_frontend.c b/libringbuffer/ring_buffer_frontend.c
index 28e959bae215641bd6e149e580802e5242aab61d..0ae3d72f23a5b16b987d5b142fcb6964bd6f0c61 100644 (file)
--- a/libringbuffer/ring_buffer_frontend.c
+++ b/libringbuffer/ring_buffer_frontend.c
@@ -53,6 +53,7 @@
 #include "backend.h"
 #include "frontend.h"
 #include "shm.h"
+#include "tlsfixup.h"
 #include "../liblttng-ust/compat.h"    /* For ENODATA */
 
 #ifndef max
@@ -1508,3 +1509,11 @@ int lib_ring_buffer_reserve_slow(struct lttng_ust_lib_ring_buffer_ctx *ctx)
        ctx->buf_offset = offsets.begin + offsets.pre_header_padding;
        return 0;
 }
+
+/*
+ * Force a read (imply TLS fixup for dlopen) of TLS variables.
+ */
+void lttng_fixup_ringbuffer_tls(void)
+{
+       asm volatile ("" : : "m" (lib_ring_buffer_nesting));
+}