package/lttng-tools: backport patch fixing pthread_setname_np failure

This patch, backported from upstream, prevent the build from failing due
to:

  [...]
    CCLD     lttng-consumerd
  ../../../src/common/.libs/libcommon.a(runas.o): In function `run_as_worker':
  /tmp/br/build/lttng-tools-2.7.0/src/common/runas.c:325: undefined reference to `pthread_setname_np'
  collect2: error: ld returned 1 exit status
  Makefile:475: recipe for target 'lttng-consumerd' failed
  [...]

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

diff --git a/package/lttng-tools/0002-Fix-Remove-dependency-on-glibc-2.12-caused-by-pthrea.patch b/package/lttng-tools/0002-Fix-Remove-dependency-on-glibc-2.12-caused-by-pthrea.patch
new file mode 100644 (file)
index 0000000..6c0fee9
--- /dev/null
+++ b/package/lttng-tools/0002-Fix-Remove-dependency-on-glibc-2.12-caused-by-pthrea.patch
@@ -0,0 +1,56 @@
+Upstream status: Merged
+Fetched from: https://git.lttng.org/?p=lttng-tools.git;a=commit;h=b8090274814e5f6a22cff0dd656e14769cc7a7df
+From b8090274814e5f6a22cff0dd656e14769cc7a7df Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?J=C3=A9r=C3=A9mie=20Galarneau?=
+ <jeremie.galarneau@efficios.com>
+Date: Wed, 30 Sep 2015 16:48:12 -0400
+Subject: [PATCH] Fix: Remove dependency on glibc 2.12 caused by
+ pthread_setname_np
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+prctl() can be used to set the same attribute set by
+pthread_setname_np, but doesn't introduce a dependency on a newer
+glibc. Using prctl(PR_SET_NAME) introduces a soft dependency on
+Linux 2.6.9. However, the worker won't fail to launch if the call
+fails as it is set out of convenience (debugger output).
+
+Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
+Signed-off-by: Samuel Martin <s.martin49@gmail.com>
+---
+ src/common/runas.c | 10 +++++-----
+ 1 file changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/src/common/runas.c b/src/common/runas.c
+index 3826c61..bc7356b 100644
+--- a/src/common/runas.c
++++ b/src/common/runas.c
+@@ -31,6 +31,7 @@
+ #include <sched.h>
+ #include <sys/signal.h>
+ #include <assert.h>
++#include <sys/prctl.h>
+ 
+ #include <common/common.h>
+ #include <common/utils.h>
+@@ -322,12 +323,11 @@ int run_as_worker(struct run_as_worker *worker)
+       memset(worker->procname, 0, proc_orig_len);
+       strncpy(worker->procname, DEFAULT_RUN_AS_WORKER_NAME, proc_orig_len);
+ 
+-      ret = pthread_setname_np(pthread_self(), DEFAULT_RUN_AS_WORKER_NAME);
++      ret = prctl(PR_SET_NAME, DEFAULT_RUN_AS_WORKER_NAME, 0, 0, 0);
+       if (ret) {
+-              errno = ret;
+-              ret = -1;
+-              PERROR("pthread_setname_np");
+-              return EXIT_FAILURE;
++              /* Don't fail as this is not essential. */
++              PERROR("prctl PR_SET_NAME");
++              ret = 0;
+       }
+ 
+       sendret.ret = 0;
+-- 
+2.6.3
+