X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=lttng-statedump-impl.c;h=e4caa488e436f0e317bcd72f89a2da79cc128c52;hb=de23d59d5992b7354b57a533b4d582809ef8d43c;hp=e9fe829f17bad251a4a985997c011c7acdd2f191;hpb=f0dbdefbdbc26a000ed546180b22144c5b48857d;p=lttng-modules.git

diff --git a/lttng-statedump-impl.c b/lttng-statedump-impl.c
index e9fe829f..e4caa488 100644
--- a/lttng-statedump-impl.c
+++ b/lttng-statedump-impl.c
@@ -79,6 +79,7 @@ struct lttng_fd_ctx {
 	char *page;
 	struct lttng_session *session;
 	struct task_struct *p;
+	struct files_struct *files;
 };
 
 /*
@@ -139,6 +140,14 @@ int lttng_enumerate_block_devices(struct lttng_session *session)
 		struct gendisk *disk = dev_to_disk(dev);
 		struct hd_struct *part;
 
+		/*
+		 * Don't show empty devices or things that have been
+		 * suppressed
+		 */
+		if (get_capacity(disk) == 0 ||
+		    (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
+			continue;
+
 		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 		while ((part = disk_part_iter_next(&piter))) {
 			char name_buf[BDEVNAME_SIZE];
@@ -209,18 +218,38 @@ int lttng_dump_one_fd(const void *p, struct file *file, unsigned int fd)
 {
 	const struct lttng_fd_ctx *ctx = p;
 	const char *s = d_path(&file->f_path, ctx->page, PAGE_SIZE);
+	unsigned int flags = file->f_flags;
+	struct fdtable *fdt;
 
+	/*
+	 * We don't expose kernel internal flags, only userspace-visible
+	 * flags.
+	 */
+	flags &= ~FMODE_NONOTIFY;
+	fdt = files_fdtable(ctx->files);
+	/*
+	 * We need to check here again whether fd is within the fdt
+	 * max_fds range, because we might be seeing a different
+	 * files_fdtable() than iterate_fd(), assuming only RCU is
+	 * protecting the read. In reality, iterate_fd() holds
+	 * file_lock, which should ensure the fdt does not change while
+	 * the lock is taken, but we are not aware whether this is
+	 * guaranteed or not, so play safe.
+	 */
+	if (fd < fdt->max_fds && test_bit(fd, fdt->close_on_exec))
+		flags |= O_CLOEXEC;
 	if (IS_ERR(s)) {
 		struct dentry *dentry = file->f_path.dentry;
 
 		/* Make sure we give at least some info */
 		spin_lock(&dentry->d_lock);
 		trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd,
-			dentry->d_name.name);
+			dentry->d_name.name, flags, file->f_mode);
 		spin_unlock(&dentry->d_lock);
 		goto end;
 	}
-	trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd, s);
+	trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd, s,
+		flags, file->f_mode);
 end:
 	return 0;
 }
@@ -230,9 +259,15 @@ void lttng_enumerate_task_fd(struct lttng_session *session,
 		struct task_struct *p, char *tmp)
 {
 	struct lttng_fd_ctx ctx = { .page = tmp, .session = session, .p = p };
+	struct files_struct *files;
 
 	task_lock(p);
-	lttng_iterate_fd(p->files, 0, lttng_dump_one_fd, &ctx);
+	files = p->files;
+	if (!files)
+		goto end;
+	ctx.files = files;
+	lttng_iterate_fd(files, 0, lttng_dump_one_fd, &ctx);
+end:
 	task_unlock(p);
 }
 
@@ -240,7 +275,11 @@ static
 int lttng_enumerate_file_descriptors(struct lttng_session *session)
 {
 	struct task_struct *p;
-	char *tmp = (char *) __get_free_page(GFP_KERNEL);
+	char *tmp;
+
+	tmp = (char *) __get_free_page(GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
 
 	/* Enumerate active file descriptors */
 	rcu_read_lock();
@@ -306,7 +345,7 @@ int lttng_enumerate_vm_maps(struct lttng_session *session)
 #endif
 
 static
-void lttng_list_interrupts(struct lttng_session *session)
+int lttng_list_interrupts(struct lttng_session *session)
 {
 	unsigned int irq;
 	unsigned long flags = 0;
@@ -328,15 +367,20 @@ void lttng_list_interrupts(struct lttng_session *session)
 		wrapper_desc_spin_unlock(&desc->lock);
 		local_irq_restore(flags);
 	}
+	return 0;
 #undef irq_to_desc
 }
 #else
 static inline
-void lttng_list_interrupts(struct lttng_session *session)
+int lttng_list_interrupts(struct lttng_session *session)
 {
+	return 0;
 }
 #endif
 
+/*
+ * Called with task lock held.
+ */
 static
 void lttng_statedump_process_ns(struct lttng_session *session,
 		struct task_struct *p,
@@ -348,8 +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 {
@@ -361,7 +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
@@ -434,15 +490,35 @@ void lttng_statedump_work_func(struct work_struct *work)
 static
 int do_lttng_statedump(struct lttng_session *session)
 {
-	int cpu;
+	int cpu, ret;
 
 	trace_lttng_statedump_start(session);
-	lttng_enumerate_process_states(session);
-	lttng_enumerate_file_descriptors(session);
-	/* FIXME lttng_enumerate_vm_maps(session); */
-	lttng_list_interrupts(session);
-	lttng_enumerate_network_ip_interface(session);
-	lttng_enumerate_block_devices(session);
+	ret = lttng_enumerate_process_states(session);
+	if (ret)
+		return ret;
+	ret = lttng_enumerate_file_descriptors(session);
+	if (ret)
+		return ret;
+	/*
+	 * FIXME
+	 * ret = lttng_enumerate_vm_maps(session);
+	 * if (ret)
+	 * 	return ret;
+	 */
+	ret = lttng_list_interrupts(session);
+	if (ret)
+		return ret;
+	ret = lttng_enumerate_network_ip_interface(session);
+	if (ret)
+		return ret;
+	ret = lttng_enumerate_block_devices(session);
+	switch (ret) {
+	case -ENOSYS:
+		printk(KERN_WARNING "LTTng: block device enumeration is not supported by kernel\n");
+		break;
+	default:
+		return ret;
+	}
 
 	/* TODO lttng_dump_idt_table(session); */
 	/* TODO lttng_dump_softirq_vec(session); */