libguestfs/0001-virt-df-parallel-Compile-debugging-messages-in-alway.patch
Richard W.M. Jones 84b1660786 Enable debugging messages in parallel virt-alignment-scan, virt-df
in order to debug possible race condition seen in Koji.
2013-09-03 12:55:08 +01:00

108 lines
3.5 KiB
Diff

From d512fb4a1a98be294d11d5de88eabcfc2be8e964 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Tue, 3 Sep 2013 12:44:25 +0100
Subject: [PATCH] virt-df: parallel: Compile debugging messages in always.
Enable debugging messages whenever LIBGUESTFS_DEBUG=1 / -v option, so
that we can track down possible race condition seen in Koji.
---
df/parallel.c | 26 ++++++++++++++++++--------
1 file changed, 18 insertions(+), 8 deletions(-)
diff --git a/df/parallel.c b/df/parallel.c
index a06e370..1a47b34 100644
--- a/df/parallel.c
+++ b/df/parallel.c
@@ -42,8 +42,6 @@
#if defined(HAVE_LIBVIRT)
-#define DEBUG_PARALLEL 0
-
/* Maximum number of threads we would ever run. Note this should not
* be > 20, unless libvirt is modified to increase the maximum number
* of clients.
@@ -70,6 +68,7 @@ static void thread_failure (const char *fn, int err);
static void *worker_thread (void *arg);
struct thread_data {
+ size_t thread_num; /* Thread number. */
int trace, verbose; /* Flags from the options_handle. */
work_fn work;
int r; /* Used to store the error status. */
@@ -96,6 +95,7 @@ start_threads (size_t option_P, guestfs_h *options_handle, work_fn work)
pthread_t threads[nr_threads];
for (i = 0; i < nr_threads; ++i) {
+ thread_data[i].thread_num = i;
if (options_handle) {
thread_data[i].trace = guestfs_get_trace (options_handle);
thread_data[i].verbose = guestfs_get_verbose (options_handle);
@@ -137,6 +137,9 @@ worker_thread (void *thread_data_vp)
thread_data->r = 0;
+ if (thread_data->verbose)
+ printf ("thread %zu starting\n", thread_data->thread_num);
+
while (1) {
size_t i; /* The current domain we're working on. */
FILE *fp;
@@ -146,6 +149,9 @@ worker_thread (void *thread_data_vp)
int err;
/* Take the next domain from the list. */
+ if (thread_data->verbose)
+ printf ("thread %zu waiting to get work\n", thread_data->thread_num);
+
err = pthread_mutex_lock (&take_mutex);
if (err != 0) {
thread_failure ("pthread_mutex_lock", err);
@@ -163,8 +169,8 @@ worker_thread (void *thread_data_vp)
if (i >= nr_domains) /* Work finished. */
break;
- if (DEBUG_PARALLEL)
- printf ("thread taking domain %zu\n", i);
+ if (thread_data->verbose)
+ printf ("thread %zu taking domain %zu\n", thread_data->thread_num, i);
fp = open_memstream (&output, &output_len);
if (fp == NULL) {
@@ -195,6 +201,10 @@ worker_thread (void *thread_data_vp)
/* Retire this domain. We have to retire domains in order, which
* may mean waiting for another thread to finish here.
*/
+ if (thread_data->verbose)
+ printf ("thread %zu waiting to retire domain %zu\n",
+ thread_data->thread_num, i);
+
err = pthread_mutex_lock (&retire_mutex);
if (err != 0) {
thread_failure ("pthread_mutex_lock", err);
@@ -210,8 +220,8 @@ worker_thread (void *thread_data_vp)
}
}
- if (DEBUG_PARALLEL)
- printf ("thread retiring domain %zu\n", i);
+ if (thread_data->verbose)
+ printf ("thread %zu retiring domain %zu\n", thread_data->thread_num, i);
/* Retire domain. */
printf ("%s", output);
@@ -227,8 +237,8 @@ worker_thread (void *thread_data_vp)
}
}
- if (DEBUG_PARALLEL)
- printf ("thread exiting\n");
+ if (thread_data->verbose)
+ printf ("thread %zu exiting\n", thread_data->thread_num);
return &thread_data->r;
}
--
1.8.3.1