block: Add statistics for failed and invalid I/O operations

This patch adds the block_acct_failed() and block_acct_invalid()
functions to allow keeping track of failed and invalid I/O operations.

The number of failed and invalid operations is exposed in
BlockDeviceStats.

We don't keep track of the time spent on invalid operations because
they are cancelled immediately when they are started.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: a7256ccb883a86356b1c6c46b5a29ed5448546a5.1446044837.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block/accounting.c b/block/accounting.c
index d427fa8fb83ffca1f0fd42cfd34a11dd8280b39c..49a9444377175e870052144a4b16780a57106b79 100644 (file)
--- a/block/accounting.c
+++ b/block/accounting.c
@@ -51,6 +51,29 @@ void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
     stats->last_access_time_ns = time_ns;
 }
 
+void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie)
+{
+    int64_t time_ns = qemu_clock_get_ns(clock_type);
+
+    assert(cookie->type < BLOCK_MAX_IOTYPE);
+
+    stats->failed_ops[cookie->type]++;
+    stats->total_time_ns[cookie->type] += time_ns - cookie->start_time_ns;
+    stats->last_access_time_ns = time_ns;
+}
+
+void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type)
+{
+    assert(type < BLOCK_MAX_IOTYPE);
+
+    /* block_acct_done() and block_acct_failed() update
+     * total_time_ns[], but this one does not. The reason is that
+     * invalid requests are accounted during their submission,
+     * therefore there's no actual I/O involved. */
+
+    stats->invalid_ops[type]++;
+    stats->last_access_time_ns = qemu_clock_get_ns(clock_type);
+}
 
 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
                       int num_requests)

diff --git a/block/qapi.c b/block/qapi.c
index 97996567614458cbbf1f444e90e99386a6b11e28..d1a6bdc1d269b9d29adc0e9ea5084243875b433b 100644 (file)
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -351,6 +351,16 @@ static BlockStats *bdrv_query_stats(const BlockDriverState *bs,
         s->stats->wr_bytes = stats->nr_bytes[BLOCK_ACCT_WRITE];
         s->stats->rd_operations = stats->nr_ops[BLOCK_ACCT_READ];
         s->stats->wr_operations = stats->nr_ops[BLOCK_ACCT_WRITE];
+
+        s->stats->failed_rd_operations = stats->failed_ops[BLOCK_ACCT_READ];
+        s->stats->failed_wr_operations = stats->failed_ops[BLOCK_ACCT_WRITE];
+        s->stats->failed_flush_operations = stats->failed_ops[BLOCK_ACCT_FLUSH];
+
+        s->stats->invalid_rd_operations = stats->invalid_ops[BLOCK_ACCT_READ];
+        s->stats->invalid_wr_operations = stats->invalid_ops[BLOCK_ACCT_WRITE];
+        s->stats->invalid_flush_operations =
+            stats->invalid_ops[BLOCK_ACCT_FLUSH];
+
         s->stats->rd_merged = stats->merged[BLOCK_ACCT_READ];
         s->stats->wr_merged = stats->merged[BLOCK_ACCT_WRITE];
         s->stats->flush_operations = stats->nr_ops[BLOCK_ACCT_FLUSH];

diff --git a/include/block/accounting.h b/include/block/accounting.h
index 4b2b999bd0bdd65a02be5a2760194be30e4889f7..b50e3cc8d22903b45bc761ee71844e65e4ef185e 100644 (file)
--- a/include/block/accounting.h
+++ b/include/block/accounting.h
@@ -38,6 +38,8 @@ enum BlockAcctType {
 typedef struct BlockAcctStats {
     uint64_t nr_bytes[BLOCK_MAX_IOTYPE];
     uint64_t nr_ops[BLOCK_MAX_IOTYPE];
+    uint64_t invalid_ops[BLOCK_MAX_IOTYPE];
+    uint64_t failed_ops[BLOCK_MAX_IOTYPE];
     uint64_t total_time_ns[BLOCK_MAX_IOTYPE];
     uint64_t merged[BLOCK_MAX_IOTYPE];
     int64_t last_access_time_ns;
@@ -52,6 +54,8 @@ typedef struct BlockAcctCookie {
 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
                       int64_t bytes, enum BlockAcctType type);
 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie);
+void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie);
+void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type);
 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
                            int num_requests);
 int64_t block_acct_idle_time_ns(BlockAcctStats *stats);

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 597281821b8f620c02b5f08f66eb07377a5740ae..009b7c88f919e5796cb995b11530890fa138156b 100644 (file)
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -452,6 +452,24 @@
 #                nanoseconds. If the field is absent it means that
 #                there haven't been any operations yet (Since 2.5).
 #
+# @failed_rd_operations: The number of failed read operations
+#                        performed by the device (Since 2.5)
+#
+# @failed_wr_operations: The number of failed write operations
+#                        performed by the device (Since 2.5)
+#
+# @failed_flush_operations: The number of failed flush operations
+#                           performed by the device (Since 2.5)
+#
+# @invalid_rd_operations: The number of invalid read operations
+#                          performed by the device (Since 2.5)
+#
+# @invalid_wr_operations: The number of invalid write operations
+#                         performed by the device (Since 2.5)
+#
+# @invalid_flush_operations: The number of invalid flush operations
+#                            performed by the device (Since 2.5)
+#
 # Since: 0.14.0
 ##
 { 'struct': 'BlockDeviceStats',
@@ -459,7 +477,10 @@
            'wr_operations': 'int', 'flush_operations': 'int',
            'flush_total_time_ns': 'int', 'wr_total_time_ns': 'int',
            'rd_total_time_ns': 'int', 'wr_highest_offset': 'int',
-           'rd_merged': 'int', 'wr_merged': 'int', '*idle_time_ns': 'int' } }
+           'rd_merged': 'int', 'wr_merged': 'int', '*idle_time_ns': 'int',
+           'failed_rd_operations': 'int', 'failed_wr_operations': 'int',
+           'failed_flush_operations': 'int', 'invalid_rd_operations': 'int',
+           'invalid_wr_operations': 'int', 'invalid_flush_operations': 'int'  } }
 
 ##
 # @BlockStats:

diff --git a/qmp-commands.hx b/qmp-commands.hx
index 5c4c16fe9b9d7d4410755437d75042d62fcec2b5..b031df6942ed733c69ee36580bbeb2d307dc2b4e 100644 (file)
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2587,6 +2587,18 @@ Each json-object contain the following:
                       nanoseconds. If the field is absent it means
                       that there haven't been any operations yet
                       (json-int, optional)
+    - "failed_rd_operations": number of failed read operations
+                              (json-int)
+    - "failed_wr_operations": number of failed write operations
+                              (json-int)
+    - "failed_flush_operations": number of failed flush operations
+                               (json-int)
+    - "invalid_rd_operations": number of invalid read operations
+                               (json-int)
+    - "invalid_wr_operations": number of invalid write operations
+                               (json-int)
+    - "invalid_flush_operations": number of invalid flush operations
+                                  (json-int)
 - "parent": Contains recursively the statistics of the underlying
             protocol (e.g. the host file for a qcow2 image). If there is
             no underlying protocol, this field is omitted