diff options
Diffstat (limited to 'meta/recipes-kernel/lttng/lttng-modules/Update-statedump-to-3.17-nsproxy-locking.patch')
| -rw-r--r-- | meta/recipes-kernel/lttng/lttng-modules/Update-statedump-to-3.17-nsproxy-locking.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/meta/recipes-kernel/lttng/lttng-modules/Update-statedump-to-3.17-nsproxy-locking.patch b/meta/recipes-kernel/lttng/lttng-modules/Update-statedump-to-3.17-nsproxy-locking.patch new file mode 100644 index 0000000000..0f18c8a3e6 --- /dev/null +++ b/meta/recipes-kernel/lttng/lttng-modules/Update-statedump-to-3.17-nsproxy-locking.patch @@ -0,0 +1,70 @@ +Upstream-Status: Backport +Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com> + +From 4ba1f53c5aebb4433fedc25d65af010274985043 Mon Sep 17 00:00:00 2001 +From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> +Date: Thu, 21 Aug 2014 10:53:12 -0400 +Subject: [PATCH 2/3] Update statedump to 3.17 nsproxy locking + +This Linux upstream commit introduces locking strategy back and forth: + +commit 728dba3a39c66b3d8ac889ddbe38b5b1c264aec3 +Author: Eric W. Biederman <ebiederm@xmission.com> +Date: Mon Feb 3 19:13:49 2014 -0800 + + namespaces: Use task_lock and not rcu to protect nsproxy + +Use the task lock starting from kernel 3.17 rather than RCU to access +the task nsproxy. + +Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> +--- + lttng-statedump-impl.c | 15 +++++++++++++++ + 1 file changed, 15 insertions(+) + +diff --git a/lttng-statedump-impl.c b/lttng-statedump-impl.c +index dad51ddaa250..e4caa488e436 100644 +--- a/lttng-statedump-impl.c ++++ b/lttng-statedump-impl.c +@@ -378,6 +378,9 @@ int lttng_list_interrupts(struct lttng_session *session) + } + #endif + ++/* ++ * Called with task lock held. ++ */ + static + void lttng_statedump_process_ns(struct lttng_session *session, + struct task_struct *p, +@@ -389,8 +392,18 @@ void lttng_statedump_process_ns(struct lttng_session *session, + struct nsproxy *proxy; + struct pid_namespace *pid_ns; + ++ /* ++ * Back and forth on locking strategy within Linux upstream for nsproxy. ++ * See Linux upstream commit 728dba3a39c66b3d8ac889ddbe38b5b1c264aec3 ++ * "namespaces: Use task_lock and not rcu to protect nsproxy" ++ * for details. ++ */ ++#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,17,0)) + rcu_read_lock(); + proxy = task_nsproxy(p); ++#else /* #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,17,0)) */ ++ proxy = p->nsproxy; ++#endif /* #else #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,17,0)) */ + if (proxy) { + pid_ns = lttng_get_proxy_pid_ns(proxy); + do { +@@ -402,7 +415,9 @@ void lttng_statedump_process_ns(struct lttng_session *session, + trace_lttng_statedump_process_state(session, + p, type, mode, submode, status, NULL); + } ++#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,17,0)) + rcu_read_unlock(); ++#endif /* #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,17,0)) */ + } + + static +-- +1.8.1.2 + |