Version 2.5.6

[lttng-modules.git] / lttng-statedump-impl.c

diff --git a/lttng-statedump-impl.c b/lttng-statedump-impl.c
index 17b02faf2be564385ff3c2bd5b7a210ef77988d8..f8613525f06cbe738c4870af8d0a7a27de7c9442 100644 (file)
--- a/lttng-statedump-impl.c
+++ b/lttng-statedump-impl.c
@@ -56,6 +56,7 @@
 #include "wrapper/irq.h"
 #include "wrapper/tracepoint.h"
 #include "wrapper/genhd.h"
+#include "wrapper/time.h"
 
 #ifdef CONFIG_LTTNG_HAS_LIST_IRQ
 #include <linux/irq.h>
@@ -213,18 +214,6 @@ int lttng_enumerate_network_ip_interface(struct lttng_session *session)
 }
 #endif /* CONFIG_INET */
 
-#ifdef FD_ISSET        /* For old kernels lacking close_on_exec() */
-static inline bool lttng_close_on_exec(int fd, const struct fdtable *fdt)
-{
-       return FD_ISSET(fd, fdt->close_on_exec);
-}
-#else
-static inline bool lttng_close_on_exec(int fd, const struct fdtable *fdt)
-{
-       return close_on_exec(fd, fdt);
-}
-#endif
-
 static
 int lttng_dump_one_fd(const void *p, struct file *file, unsigned int fd)
 {
@@ -390,6 +379,9 @@ 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,
@@ -401,8 +393,20 @@ 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) || \
+               LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \
+               LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0))
+       proxy = p->nsproxy;
+#else
        rcu_read_lock();
        proxy = task_nsproxy(p);
+#endif
        if (proxy) {
                pid_ns = lttng_get_proxy_pid_ns(proxy);
                do {
@@ -414,7 +418,13 @@ 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) || \
+               LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \
+               LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0))
+       /* (nothing) */
+#else
        rcu_read_unlock();
+#endif
 }
 
 static
@@ -510,6 +520,8 @@ int do_lttng_statedump(struct lttng_session *session)
                return ret;
        ret = lttng_enumerate_block_devices(session);
        switch (ret) {
+       case 0:
+               break;
        case -ENOSYS:
                printk(KERN_WARNING "LTTng: block device enumeration is not supported by kernel\n");
                break;