From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Tue, 9 Jun 2015 09:51:06 +0000 (+0200)
Subject: Fix: fetch caller address from tracef()
X-Git-Tag: v2.5.5~6
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=bb71dcac355e56ed06e1a1c4f765aa27ed1b7f82;p=lttng-ust.git

Fix: fetch caller address from tracef()

Don't fetch the address within the ust trampoline, but rather the caller
address.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/include/lttng/lttng-ust-tracef.h b/include/lttng/lttng-ust-tracef.h
index 1910447f..3095b3db 100644
--- a/include/lttng/lttng-ust-tracef.h
+++ b/include/lttng/lttng-ust-tracef.h
@@ -24,7 +24,7 @@
 #include <stdarg.h>
 
 TRACEPOINT_EVENT(lttng_ust_tracef, event,
-	TP_ARGS(const char *, msg, unsigned int, len),
+	TP_ARGS(const char *, msg, unsigned int, len, void *, ip),
 	TP_FIELDS(
 		ctf_sequence_text(char, msg, msg, unsigned int, len)
 	)
diff --git a/include/lttng/ust-tracepoint-event.h b/include/lttng/ust-tracepoint-event.h
index 3f99f662..6c32249c 100644
--- a/include/lttng/ust-tracepoint-event.h
+++ b/include/lttng/ust-tracepoint-event.h
@@ -565,6 +565,13 @@ size_t __event_get_align__##_provider##___##_name(_TP_ARGS_PROTO(_args))      \
 #define _TP_SESSION_CHECK(session, csession)   1
 #endif /* TP_SESSION_CHECK */
 
+#undef _TP_IP_PARAM
+#ifdef TP_IP_PARAM
+#define _TP_IP_PARAM()		ip
+#else /* TP_IP_PARAM */
+#define _TP_IP_PARAM()		__builtin_return_address(0)
+#endif /* TP_IP_PARAM */
+
 /*
  * Using twice size for filter stack data to hold size and pointer for
  * each field (worse case). For integers, max size required is 64-bit.
@@ -621,7 +628,7 @@ void __event_probe__##_provider##___##_name(_TP_ARGS_DATA_PROTO(_args))	      \
 	__event_align = __event_get_align__##_provider##___##_name(_TP_ARGS_VAR(_args)); \
 	lib_ring_buffer_ctx_init(&__ctx, __chan->chan, __event, __event_len,  \
 				 __event_align, -1, __chan->handle);	      \
-	__ctx.ip = __builtin_return_address(0);				      \
+	__ctx.ip = _TP_IP_PARAM();					      \
 	__ret = __chan->ops->event_reserve(&__ctx, __event->id);	      \
 	if (__ret < 0)							      \
 		return;							      \
diff --git a/liblttng-ust/lttng-ust-tracef-provider.h b/liblttng-ust/lttng-ust-tracef-provider.h
index 1e328884..2afd7f99 100644
--- a/liblttng-ust/lttng-ust-tracef-provider.h
+++ b/liblttng-ust/lttng-ust-tracef-provider.h
@@ -30,6 +30,7 @@
 
 #endif /* _TRACEPOINT_LTTNG_UST_TRACEF_PROVIDER_H */
 
+#define TP_IP_PARAM	/* IP context received as parameter */
 #undef TRACEPOINT_INCLUDE
 #define TRACEPOINT_INCLUDE "./lttng-ust-tracef.h"
 
diff --git a/liblttng-ust/tracef.c b/liblttng-ust/tracef.c
index 9ef063ce..dcae3be7 100644
--- a/liblttng-ust/tracef.c
+++ b/liblttng-ust/tracef.c
@@ -39,7 +39,8 @@ void _lttng_ust_tracef(const char *fmt, ...)
 	/* len does not include the final \0 */
 	if (len < 0)
 		goto end;
-	__tracepoint_cb_lttng_ust_tracef___event(msg, len);
+	__tracepoint_cb_lttng_ust_tracef___event(msg, len,
+		__builtin_return_address(0));
 	free(msg);
 end:
 	va_end(ap);