qcow2: Add some tracing

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c
index 340a6f2b26..710d4b1828 100644
--- a/block/qcow2-cache.c
+++ b/block/qcow2-cache.c
@@ -25,6 +25,7 @@
 #include "block_int.h"
 #include "qemu-common.h"
 #include "qcow2.h"
+#include "trace.h"
 
 typedef struct Qcow2CachedTable {
     void*   table;
@@ -100,6 +101,9 @@ static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
         return 0;
     }
 
+    trace_qcow2_cache_entry_flush(qemu_coroutine_self(),
+                                  c == s->l2_table_cache, i);
+
     if (c->depends) {
         ret = qcow2_cache_flush_dependency(bs, c);
     } else if (c->depends_on_flush) {
@@ -132,10 +136,13 @@ static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
 
 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c)
 {
+    BDRVQcowState *s = bs->opaque;
     int result = 0;
     int ret;
     int i;
 
+    trace_qcow2_cache_flush(qemu_coroutine_self(), c == s->l2_table_cache);
+
     for (i = 0; i < c->size; i++) {
         ret = qcow2_cache_entry_flush(bs, c, i);
         if (ret < 0 && result != -ENOSPC) {
@@ -218,6 +225,9 @@ static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
     int i;
     int ret;
 
+    trace_qcow2_cache_get(qemu_coroutine_self(), c == s->l2_table_cache,
+                          offset, read_from_disk);
+
     /* Check if the table is already cached */
     for (i = 0; i < c->size; i++) {
         if (c->entries[i].offset == offset) {
@@ -227,6 +237,8 @@ static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
 
     /* If not, write a table back and replace it */
     i = qcow2_cache_find_entry_to_replace(c);
+    trace_qcow2_cache_get_replace_entry(qemu_coroutine_self(),
+                                        c == s->l2_table_cache, i);
     if (i < 0) {
         return i;
     }
@@ -236,6 +248,8 @@ static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
         return ret;
     }
 
+    trace_qcow2_cache_get_read(qemu_coroutine_self(),
+                               c == s->l2_table_cache, i);
     c->entries[i].offset = 0;
     if (read_from_disk) {
         if (c == s->l2_table_cache) {
@@ -258,6 +272,10 @@ found:
     c->entries[i].cache_hits++;
     c->entries[i].ref++;
     *table = c->entries[i].table;
+
+    trace_qcow2_cache_get_done(qemu_coroutine_self(),
+                               c == s->l2_table_cache, i);
+
     return 0;
 }