Libguestfs - Apr 2011 - [PATCH 0/4] Add progress messages to guestfs_launch function.

These four commits add approximate progress messages to the
guestfs_launch function.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top
-------------- next part --------------
>From b8fd17fa0b5c91ad657a2dc765864711ed95ef1c Mon Sep 17 00:00:00 2001
From: Richard W.M. Jones <rjones at redhat.com>
Date: Fri, 1 Apr 2011 13:30:24 +0100
Subject: [PATCH 1/4] Add prototype for timeval_diff.

This is just code motion.
---
 src/launch.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/launch.c b/src/launch.c
index 8074d13..367d3ff 100644
--- a/src/launch.c
+++ b/src/launch.c
@@ -1,5 +1,5 @@
 /* libguestfs
- * Copyright (C) 2009-2010 Red Hat Inc.
+ * Copyright (C) 2009-2011 Red Hat Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -71,6 +71,7 @@
 #include "guestfs_protocol.h"
 
 static int launch_appliance (guestfs_h *g);
+static int64_t timeval_diff (const struct timeval *x, const struct timeval *y);
 static int connect_unix_socket (guestfs_h *g, const char *sock);
 static int qemu_supports (guestfs_h *g, const char *option);
 
-- 
1.7.4.1

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top
-------------- next part --------------
>From 21434b17986fe45950bb9cac1bb546ea3cd95de7 Mon Sep 17 00:00:00 2001
From: Richard W.M. Jones <rjones at redhat.com>
Date: Fri, 1 Apr 2011 12:17:22 +0100
Subject: [PATCH 2/4] Shared function to send progress messages.

This is just code motion.
---
 src/guestfs-internal.h |    4 +++-
 src/proto.c            |   10 ++++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/guestfs-internal.h b/src/guestfs-internal.h
index b5f50c9..2729097 100644
--- a/src/guestfs-internal.h
+++ b/src/guestfs-internal.h
@@ -1,5 +1,5 @@
 /* libguestfs
- * Copyright (C) 2009-2010 Red Hat Inc.
+ * Copyright (C) 2009-2011 Red Hat Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -266,6 +266,7 @@ struct inspect_fstab_entry {
 
 struct guestfs_message_header;
 struct guestfs_message_error;
+struct guestfs_progress;
 
 extern void guestfs_error (guestfs_h *g, const char *fs, ...)
   __attribute__((format (printf,2,3)));
@@ -299,6 +300,7 @@ extern int guestfs___recv_file (guestfs_h *g, const char
*filename);
 extern int guestfs___send_to_daemon (guestfs_h *g, const void *v_buf, size_t
n);
 extern int guestfs___recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void
**buf_rtn);
 extern int guestfs___accept_from_daemon (guestfs_h *g);
+extern void guestfs___progress_message_callback (guestfs_h *g, const struct
guestfs_progress *message);
 extern int guestfs___build_appliance (guestfs_h *g, char **kernel, char
**initrd, char **appliance);
 extern void guestfs___print_BufferIn (FILE *out, const char *buf, size_t
buf_size);
 extern void guestfs___print_BufferOut (FILE *out, const char *buf, size_t
buf_size);
diff --git a/src/proto.c b/src/proto.c
index cda731e..39f30ae 100644
--- a/src/proto.c
+++ b/src/proto.c
@@ -326,8 +326,10 @@ really_read_from_socket (guestfs_h *g, int sock, char *buf,
size_t n)
   return (ssize_t) got;
 }
 
-static void
-send_progress_message (guestfs_h *g, const guestfs_progress *message)
+/* Convenient wrapper to generate a progress message callback. */
+void
+guestfs___progress_message_callback (guestfs_h *g,
+                                     const guestfs_progress *message)
 {
   uint64_t array[4];
 
@@ -384,7 +386,7 @@ check_for_daemon_cancellation_or_eof (guestfs_h *g, int fd)
       xdr_guestfs_progress (&xdr, &message);
       xdr_destroy (&xdr);
 
-      send_progress_message (g, &message);
+      guestfs___progress_message_callback (g, &message);
     }
 
     return 0;
@@ -674,7 +676,7 @@ guestfs___recv_from_daemon (guestfs_h *g, uint32_t
*size_rtn, void **buf_rtn)
       xdr_guestfs_progress (&xdr, &message);
       xdr_destroy (&xdr);
 
-      send_progress_message (g, &message);
+      guestfs___progress_message_callback (g, &message);
     }
 
     free (*buf_rtn);
-- 
1.7.4.1

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
New in Fedora 11: Fedora Windows cross-compiler. Compile Windows
programs, test, and build Windows installers. Over 70 libraries supprt'd
http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw
-------------- next part --------------
>From 6962c003785f48b859fedaabc77ebe0dfe85e993 Mon Sep 17 00:00:00 2001
From: Richard W.M. Jones <rjones at redhat.com>
Date: Fri, 1 Apr 2011 13:29:06 +0100
Subject: [PATCH 3/4] protocol: Sleep for 1ms before reading log messages.

As explained in the comment:

  /* QEMU's console emulates a 16550A serial port.  The real 16550A
   * device has a small FIFO buffer (16 bytes) which means here we see
   * lots of small reads of 1-16 bytes in length, usually single
   * bytes.  Sleeping here for a very brief period groups reads
   * together (so we usually get a few lines of output at once) and
   * improves overall throughput, as well as making the event
   * interface a bit more sane for callers.  With a virtio-serial
   * based console (not yet implemented) we may be able to remove
   * this.  XXX
   */
---
 src/proto.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/src/proto.c b/src/proto.c
index 39f30ae..7cd1d31 100644
--- a/src/proto.c
+++ b/src/proto.c
@@ -251,8 +251,15 @@ read_log_message_or_eof (guestfs_h *g, int fd, int
error_if_eof)
   /* QEMU's console emulates a 16550A serial port.  The real 16550A
    * device has a small FIFO buffer (16 bytes) which means here we see
    * lots of small reads of 1-16 bytes in length, usually single
-   * bytes.
+   * bytes.  Sleeping here for a very brief period groups reads
+   * together (so we usually get a few lines of output at once) and
+   * improves overall throughput, as well as making the event
+   * interface a bit more sane for callers.  With a virtio-serial
+   * based console (not yet implemented) we may be able to remove
+   * this.  XXX
    */
+  usleep (1000);
+
   n = read (fd, buf, sizeof buf);
   if (n == 0) {
     /* Hopefully this indicates the qemu child process has died. */
-- 
1.7.4.1

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://et.redhat.com/~rjones/virt-df/
-------------- next part --------------
>From ea70a3e0ab34cac40151ebfbddb5a5e03bc7cbc6 Mon Sep 17 00:00:00 2001
From: Richard W.M. Jones <rjones at redhat.com>
Date: Fri, 1 Apr 2011 13:30:48 +0100
Subject: [PATCH 4/4] Generate progress messages during launch.

This commit generates approximate progress messages during the
guestfs_launch call.  Currently this code generates:

   0 / 12: launch clock starts
   3 / 12: appliance created
   6 / 12: detected that guest kernel started
   9 / 12: detected that /init script is running
  12 / 12: launch completed successfully

(Note this is not an ABI and may be changed or removed in a future
version).

Progress messages are only generated at all if 5 seconds have elapsed
since the launch, and they are only generated for the ordinary
appliance (not if using attach-method to attach to an existing virtio
serial port).
---
 src/guestfs-internal.h |    1 +
 src/launch.c           |   35 +++++++++++++++++++++++++++++++++++
 src/proto.c            |   18 ++++++++++++++++++
 3 files changed, 54 insertions(+), 0 deletions(-)

diff --git a/src/guestfs-internal.h b/src/guestfs-internal.h
index 2729097..3a63f2e 100644
--- a/src/guestfs-internal.h
+++ b/src/guestfs-internal.h
@@ -302,6 +302,7 @@ extern int guestfs___recv_from_daemon (guestfs_h *g,
uint32_t *size_rtn, void **
 extern int guestfs___accept_from_daemon (guestfs_h *g);
 extern void guestfs___progress_message_callback (guestfs_h *g, const struct
guestfs_progress *message);
 extern int guestfs___build_appliance (guestfs_h *g, char **kernel, char
**initrd, char **appliance);
+extern void guestfs___launch_send_progress (guestfs_h *g, int perdozen);
 extern void guestfs___print_BufferIn (FILE *out, const char *buf, size_t
buf_size);
 extern void guestfs___print_BufferOut (FILE *out, const char *buf, size_t
buf_size);
 #ifdef HAVE_PCRE
diff --git a/src/launch.c b/src/launch.c
index 367d3ff..a60ef7b 100644
--- a/src/launch.c
+++ b/src/launch.c
@@ -407,12 +407,15 @@ launch_appliance (guestfs_h *g)
 
   /* Start the clock ... */
   gettimeofday (&g->launch_t, NULL);
+  guestfs___launch_send_progress (g, 0);
 
   /* Locate and/or build the appliance. */
   char *kernel = NULL, *initrd = NULL, *appliance = NULL;
   if (guestfs___build_appliance (g, &kernel, &initrd, &appliance)
== -1)
     return -1;
 
+  guestfs___launch_send_progress (g, 3);
+
   if (g->verbose)
     guestfs___print_timestamped_message (g, "begin testing qemu
features");
 
@@ -761,6 +764,8 @@ launch_appliance (guestfs_h *g)
     goto cleanup1;
   }
 
+  guestfs___launch_send_progress (g, 12);
+
   return 0;
 
  cleanup1:
@@ -862,6 +867,36 @@ connect_unix_socket (guestfs_h *g, const char *sockpath)
   return -1;
 }
 
+/* launch (of the ordinary appliance) generates approximate progress
+ * messages.  Currently these are defined as follows:
+ *
+ *    0 / 12: launch clock starts
+ *    3 / 12: appliance created
+ *    6 / 12: detected that guest kernel started
+ *    9 / 12: detected that /init script is running
+ *   12 / 12: launch completed successfully
+ *
+ * Notes:
+ * (1) This is not a documented ABI and the behaviour may be changed
+ * or removed in future.
+ * (2) Messages are only sent if more than 5 seconds has elapsed
+ * since the launch clock started.
+ * (3) There is a gross hack in proto.c to make this work.
+ */
+void
+guestfs___launch_send_progress (guestfs_h *g, int perdozen)
+{
+  struct timeval tv;
+
+  gettimeofday (&tv, NULL);
+  if (timeval_diff (&g->launch_t, &tv) >= 5000) {
+    guestfs_progress progress_message +      { .proc = 0, .serial = 0,
.position = perdozen, .total = 12 };
+
+    guestfs___progress_message_callback (g, &progress_message);
+  }
+}
+
 /* Return the location of the tmpdir (eg. "/tmp") and allow users
  * to override it at runtime using $TMPDIR.
  * http://www.pathname.com/fhs/pub/fhs-2.3.html#TMPTEMPORARYFILES
diff --git a/src/proto.c b/src/proto.c
index 7cd1d31..63aea68 100644
--- a/src/proto.c
+++ b/src/proto.c
@@ -285,6 +285,24 @@ read_log_message_or_eof (guestfs_h *g, int fd, int
error_if_eof)
   /* It's an actual log message, send it upwards if anyone is listening. */
   guestfs___call_callbacks_message (g, GUESTFS_EVENT_APPLIANCE, buf, n);
 
+  /* This is a gross hack.  See the comment above
+   * guestfs___launch_send_progress.
+   */
+  if (g->state == LAUNCHING) {
+    const char *sentinel;
+    size_t len;
+
+    sentinel = "Linux version"; /* kernel up */
+    len = strlen (sentinel);
+    if (memmem (buf, n, sentinel, len) != NULL)
+      guestfs___launch_send_progress (g, 6);
+
+    sentinel = "Starting /init script"; /* /init running */
+    len = strlen (sentinel);
+    if (memmem (buf, n, sentinel, len) != NULL)
+      guestfs___launch_send_progress (g, 9);
+  }
+
   return 0;
 }
 
-- 
1.7.4.1