[lttng-dev] [PATCH] Fix: baddr_statedump tracepoint registration

[Mathieu Desnoyers]

----- Original Message -----
> From: "Paul Woegerer" <paul_woegerer at mentor.com>
> To: lttng-dev at lists.lttng.org, "mathieu desnoyers" <mathieu.desnoyers at efficios.com>
> Sent: Tuesday, December 10, 2013 8:07:51 AM
> Subject: [PATCH] Fix: baddr_statedump tracepoint registration
> 
> Ensure baddr_statedump tracepoint registration is completed prior to
> using the tracepoint in lttng_ust_baddr_statedump().
> 
> Make liblttng-ust-dl robust for explicit baddr_statedump tracepoint
> deregistration in lttng_ust_cleanup() (prevent dlopen/dlclose to get
> traced if ust_baddr tracepoints are not available).

Merged, thanks!

Mathieu

> 
> Signed-off-by: Paul Woegerer <paul_woegerer at mentor.com>
> ---
>  liblttng-ust-dl/ustdl.c        |  4 ++--
>  liblttng-ust/lttng-ust-baddr.c | 12 ++++++++++++
>  liblttng-ust/lttng-ust-baddr.h |  3 +++
>  liblttng-ust/lttng-ust-comm.c  |  2 ++
>  4 files changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/liblttng-ust-dl/ustdl.c b/liblttng-ust-dl/ustdl.c
> index 3038d5c..ceb9b5b 100644
> --- a/liblttng-ust-dl/ustdl.c
> +++ b/liblttng-ust-dl/ustdl.c
> @@ -90,7 +90,7 @@ void lttng_ust_baddr_push(void *so_base, const char
> *so_name)
>  void *dlopen(const char *filename, int flag)
>  {
>  	void *handle = _lttng_ust_dl_libc_dlopen(filename, flag);
> -	if (handle) {
> +	if (__tracepoint_ptrs_registered && handle) {
>  		struct link_map *p = NULL;
>  		if (dlinfo(handle, RTLD_DI_LINKMAP, &p) != -1 && p != NULL
>  				&& p->l_addr != 0)
> @@ -101,7 +101,7 @@ void *dlopen(const char *filename, int flag)
>  
>  int dlclose(void *handle)
>  {
> -	if (handle) {
> +	if (__tracepoint_ptrs_registered && handle) {
>  		struct link_map *p = NULL;
>  		if (dlinfo(handle, RTLD_DI_LINKMAP, &p) != -1 && p != NULL
>  				&& p->l_addr != 0)
> diff --git a/liblttng-ust/lttng-ust-baddr.c b/liblttng-ust/lttng-ust-baddr.c
> index df0ba45..b7843e2 100644
> --- a/liblttng-ust/lttng-ust-baddr.c
> +++ b/liblttng-ust/lttng-ust-baddr.c
> @@ -194,3 +194,15 @@ int lttng_ust_baddr_statedump(void *owner)
>  	dump_exec_baddr(&data);
>  	return 0;
>  }
> +
> +void lttng_ust_baddr_statedump_init(void)
> +{
> +	__tracepoints__init();
> +	__tracepoints__ptrs_init();
> +}
> +
> +void lttng_ust_baddr_statedump_destroy(void)
> +{
> +	__tracepoints__ptrs_destroy();
> +	__tracepoints__destroy();
> +}
> diff --git a/liblttng-ust/lttng-ust-baddr.h b/liblttng-ust/lttng-ust-baddr.h
> index 08f7db7..e7a0dfb 100644
> --- a/liblttng-ust/lttng-ust-baddr.h
> +++ b/liblttng-ust/lttng-ust-baddr.h
> @@ -21,6 +21,9 @@
>  
>  #include <lttng/ust-events.h>
>  
> +void lttng_ust_baddr_statedump_init(void);
> +void lttng_ust_baddr_statedump_destroy(void);
> +
>  int lttng_ust_baddr_statedump(void *owner);
>  
>  #endif /* LTTNG_UST_BADDR_H */
> diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
> index 6eb4a89..0c96f01 100644
> --- a/liblttng-ust/lttng-ust-comm.c
> +++ b/liblttng-ust/lttng-ust-comm.c
> @@ -1343,6 +1343,7 @@ void __attribute__((constructor)) lttng_ust_init(void)
>  	 */
>  	init_usterr();
>  	init_tracepoint();
> +	lttng_ust_baddr_statedump_init();
>  	lttng_ring_buffer_metadata_client_init();
>  	lttng_ring_buffer_client_overwrite_init();
>  	lttng_ring_buffer_client_overwrite_rt_init();
> @@ -1457,6 +1458,7 @@ void lttng_ust_cleanup(int exiting)
>  	lttng_ring_buffer_client_overwrite_rt_exit();
>  	lttng_ring_buffer_client_overwrite_exit();
>  	lttng_ring_buffer_metadata_client_exit();
> +	lttng_ust_baddr_statedump_destroy();
>  	exit_tracepoint();
>  	if (!exiting) {
>  		/* Reinitialize values for fork */
> --
> 1.8.5
> 
> 

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com