This patch adds the new field 'idle_time_ns' to the BlockDeviceStats
structure, indicating the time that has passed since the previous I/O
operation.
It also adds the block_acct_idle_time_ns() call, to ensure that all
references to the clock type used for accounting are in the same
place. This will later allow us to use a different clock for iotests.
Signed-off-by: Alberto Garcia <be...@igalia.com>
---
block/accounting.c | 12 ++++++++++--
block/qapi.c | 5 +++++
hmp.c | 4 +++-
include/block/accounting.h | 2 ++
qapi/block-core.json | 6 +++++-
qmp-commands.hx | 10 ++++++++--
6 files changed, 33 insertions(+), 6 deletions(-)
diff --git a/block/accounting.c b/block/accounting.c
index 6f4c0f1..d427fa8 100644
--- a/block/accounting.c
+++ b/block/accounting.c
@@ -40,12 +40,15 @@ void block_acct_start(BlockAcctStats *stats,
BlockAcctCookie *cookie,
void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
{
+ int64_t time_ns = qemu_clock_get_ns(clock_type);
+ int64_t latency_ns = time_ns - cookie->start_time_ns;
+
assert(cookie->type < BLOCK_MAX_IOTYPE);
stats->nr_bytes[cookie->type] += cookie->bytes;
stats->nr_ops[cookie->type]++;
- stats->total_time_ns[cookie->type] +=
- qemu_clock_get_ns(clock_type) - cookie->start_time_ns;
+ stats->total_time_ns[cookie->type] += latency_ns;
+ stats->last_access_time_ns = time_ns;
}
@@ -55,3 +58,8 @@ void block_acct_merge_done(BlockAcctStats *stats, enum
BlockAcctType type,
assert(type < BLOCK_MAX_IOTYPE);
stats->merged[type] += num_requests;
}
+
+int64_t block_acct_idle_time_ns(BlockAcctStats *stats)
+{
+ return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns;
+}
diff --git a/block/qapi.c b/block/qapi.c
index ec0f513..539c2e3 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -357,6 +357,11 @@ static BlockStats *bdrv_query_stats(const BlockDriverState
*bs,
s->stats->wr_total_time_ns = stats->total_time_ns[BLOCK_ACCT_WRITE];
s->stats->rd_total_time_ns = stats->total_time_ns[BLOCK_ACCT_READ];
s->stats->flush_total_time_ns = stats->total_time_ns[BLOCK_ACCT_FLUSH];
+
+ s->stats->has_idle_time_ns = stats->last_access_time_ns > 0;
+ if (s->stats->has_idle_time_ns) {
+ s->stats->idle_time_ns = block_acct_idle_time_ns(stats);
+ }
}
s->stats->wr_highest_offset = bs->wr_highest_offset;
diff --git a/hmp.c b/hmp.c
index 28caa7d..8ee473e 100644
--- a/hmp.c
+++ b/hmp.c
@@ -522,6 +522,7 @@ void hmp_info_blockstats(Monitor *mon, const QDict *qdict)
" flush_total_time_ns=%" PRId64
" rd_merged=%" PRId64
" wr_merged=%" PRId64
+ " idle_time_ns=%" PRId64
"\n",
stats->value->stats->rd_bytes,
stats->value->stats->wr_bytes,
@@ -532,7 +533,8 @@ void hmp_info_blockstats(Monitor *mon, const QDict *qdict)
stats->value->stats->rd_total_time_ns,
stats->value->stats->flush_total_time_ns,
stats->value->stats->rd_merged,
- stats->value->stats->wr_merged);
+ stats->value->stats->wr_merged,
+ stats->value->stats->idle_time_ns);
}
qapi_free_BlockStatsList(stats_list);
diff --git a/include/block/accounting.h b/include/block/accounting.h
index 66637cd..4b2b999 100644
--- a/include/block/accounting.h
+++ b/include/block/accounting.h
@@ -40,6 +40,7 @@ typedef struct BlockAcctStats {
uint64_t nr_ops[BLOCK_MAX_IOTYPE];
uint64_t total_time_ns[BLOCK_MAX_IOTYPE];
uint64_t merged[BLOCK_MAX_IOTYPE];
+ int64_t last_access_time_ns;
} BlockAcctStats;
typedef struct BlockAcctCookie {
@@ -53,5 +54,6 @@ void block_acct_start(BlockAcctStats *stats, BlockAcctCookie
*cookie,
void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie);
void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
int num_requests);
+int64_t block_acct_idle_time_ns(BlockAcctStats *stats);
#endif
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 5f12af7..69c3e1f 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -448,6 +448,10 @@
# @wr_merged: Number of write requests that have been merged into another
# request (Since 2.3).
#
+# @idle_time_ns: #optional Time since the last I/O operation, in
+# nanoseconds. If the field is absent it means that
+# there haven't been any operations yet (Since 2.5).
+#
# Since: 0.14.0
##
{ 'struct': 'BlockDeviceStats',
@@ -455,7 +459,7 @@
'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' } }
+ 'rd_merged': 'int', 'wr_merged': 'int', '*idle_time_ns': 'int' } }
##
# @BlockStats:
diff --git a/qmp-commands.hx b/qmp-commands.hx
index ed6f4ad..f44b2ba 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2526,6 +2526,10 @@ Each json-object contain the following:
another request (json-int)
- "wr_merged": number of write requests that have been merged into
another request (json-int)
+ - "idle_time_ns": time since the last I/O operation, in
+ nanoseconds. If the field is absent it means
+ that there haven't been any operations yet
+ (json-int, optional)
- "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
@@ -2550,7 +2554,8 @@ Example:
"flush_total_times_ns":49653
"flush_operations":61,
"rd_merged":0,
- "wr_merged":0
+ "wr_merged":0,
+ "idle_time_ns":2953431879
}
},
"stats":{
@@ -2564,7 +2569,8 @@ Example:
"rd_total_times_ns":3465673657
"flush_total_times_ns":49653,
"rd_merged":0,
- "wr_merged":0
+ "wr_merged":0,
+ "idle_time_ns":2953431879
}
},
{
--
2.6.1
