e2fsck: add debug codes for multiple threads

These debug codes are added to run the multiple pass1 check
thread one by one in order. If all the codes are correct,
fsck of multiple threads should have exactly the same outcome
with single thread.

E2fsprogs-commit: a8b483a1e7987a6dddc32bc82db06f649d245630

Change-Id: I41b0493a0cd830b76434ff0f86a87c98d8d3ad22
Signed-off-by: Li Xi <lixi@ddn.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index 986d388..637f9f8 100644 (file)
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -490,6 +490,18 @@ struct e2fsck_struct {
 };
 
 #ifdef HAVE_PTHREAD
+#ifdef DEBUG_THREADS
+/*
+ * Enabling DEBUG_THREADS would cause the parallel
+ * fsck threads run sequentially.
+ */
+struct e2fsck_thread_debug {
+       pthread_mutex_t etd_mutex;
+       pthread_cond_t  etd_cond;
+       int             etd_finished_threads;
+};
+#endif
+
 struct e2fsck_thread_info {
        /* ID returned by pthread_create() */
        pthread_t                eti_thread_id;
@@ -499,7 +511,11 @@ struct e2fsck_thread_info {
        int                      eti_started;
        /* Context used for this thread */
        e2fsck_t                 eti_thread_ctx;
+#ifdef DEBUG_THREADS
+       struct e2fsck_thread_debug      *eti_debug;
+#endif
 };
+
 #endif
 
 /* Data structures to evaluate whether an extent tree needs rebuilding. */

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index cc58e45..b2d9f51 100644 (file)
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -2711,6 +2711,18 @@ static void *e2fsck_pass1_thread(void *arg)
 {
        struct e2fsck_thread_info       *info = arg;
        e2fsck_t                         thread_ctx = info->eti_thread_ctx;
+#ifdef DEBUG_THREADS
+       struct e2fsck_thread_debug      *thread_debug = info->eti_debug;
+#endif
+
+#ifdef DEBUG_THREADS
+       pthread_mutex_lock(&thread_debug->etd_mutex);
+       while (info->eti_thread_index > thread_debug->etd_finished_threads) {
+               pthread_cond_wait(&thread_debug->etd_cond,
+                                 &thread_debug->etd_mutex);
+       }
+       pthread_mutex_unlock(&thread_debug->etd_mutex);
+#endif
 
 #ifdef HAVE_SETJMP_H
        /*
@@ -2735,6 +2747,14 @@ out:
                        thread_ctx->thread_info.et_group_start,
                        thread_ctx->thread_info.et_group_end,
                        thread_ctx->thread_info.et_inode_number);
+
+#ifdef DEBUG_THREADS
+       pthread_mutex_lock(&thread_debug->etd_mutex);
+       thread_debug->etd_finished_threads++;
+       pthread_cond_broadcast(&thread_debug->etd_cond);
+       pthread_mutex_unlock(&thread_debug->etd_mutex);
+#endif
+
        return NULL;
 }
 
@@ -2748,6 +2768,12 @@ static int e2fsck_pass1_threads_start(struct e2fsck_thread_info **pinfo,
        struct e2fsck_thread_info       *tmp_pinfo;
        int                              i;
        e2fsck_t                         thread_ctx;
+#ifdef DEBUG_THREADS
+       struct e2fsck_thread_debug       thread_debug =
+               {PTHREAD_MUTEX_INITIALIZER, PTHREAD_COND_INITIALIZER, 0};
+
+       thread_debug.etd_finished_threads = 0;
+#endif
 
        retval = pthread_attr_init(&attr);
        if (retval) {
@@ -2768,6 +2794,9 @@ static int e2fsck_pass1_threads_start(struct e2fsck_thread_info **pinfo,
        for (i = 0; i < num_threads; i++) {
                tmp_pinfo = &infos[i];
                tmp_pinfo->eti_thread_index = i;
+#ifdef DEBUG_THREADS
+               tmp_pinfo->eti_debug = &thread_debug;
+#endif
                retval = e2fsck_pass1_thread_prepare(global_ctx, &thread_ctx,
                                                     i, num_threads);
                if (retval) {