From 7e5c776d15b1fc0cda00c255ba035bdf81dbaa31 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 9 Mar 2018 19:52:12 +0300 Subject: qapi: add block latency histogram interface Set (and clear) histograms through new command block-latency-histogram-set and show new statistics in query-blockstats results. For now, the command is marked experimental with prefix 'x-', to gain experience with the interface without being stuck with design decisions. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20180309165212.97144-3-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi [eblake: fix typos, mention x- prefix in commit message] Signed-off-by: Eric Blake --- block/qapi.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) (limited to 'block') diff --git a/block/qapi.c b/block/qapi.c index f2e0aa2cbe..04c6fc69b9 100644 --- a/block/qapi.c +++ b/block/qapi.c @@ -394,6 +394,37 @@ static void bdrv_query_info(BlockBackend *blk, BlockInfo **p_info, qapi_free_BlockInfo(info); } +static uint64List *uint64_list(uint64_t *list, int size) +{ + int i; + uint64List *out_list = NULL; + uint64List **pout_list = &out_list; + + for (i = 0; i < size; i++) { + uint64List *entry = g_new(uint64List, 1); + entry->value = list[i]; + *pout_list = entry; + pout_list = &entry->next; + } + + *pout_list = NULL; + + return out_list; +} + +static void bdrv_latency_histogram_stats(BlockLatencyHistogram *hist, + bool *not_null, + BlockLatencyHistogramInfo **info) +{ + *not_null = hist->bins != NULL; + if (*not_null) { + *info = g_new0(BlockLatencyHistogramInfo, 1); + + (*info)->boundaries = uint64_list(hist->boundaries, hist->nbins - 1); + (*info)->bins = uint64_list(hist->bins, hist->nbins); + } +} + static void bdrv_query_blk_stats(BlockDeviceStats *ds, BlockBackend *blk) { BlockAcctStats *stats = blk_get_stats(blk); @@ -459,6 +490,16 @@ static void bdrv_query_blk_stats(BlockDeviceStats *ds, BlockBackend *blk) dev_stats->avg_wr_queue_depth = block_acct_queue_depth(ts, BLOCK_ACCT_WRITE); } + + bdrv_latency_histogram_stats(&stats->latency_histogram[BLOCK_ACCT_READ], + &ds->has_x_rd_latency_histogram, + &ds->x_rd_latency_histogram); + bdrv_latency_histogram_stats(&stats->latency_histogram[BLOCK_ACCT_WRITE], + &ds->has_x_wr_latency_histogram, + &ds->x_wr_latency_histogram); + bdrv_latency_histogram_stats(&stats->latency_histogram[BLOCK_ACCT_FLUSH], + &ds->has_x_flush_latency_histogram, + &ds->x_flush_latency_histogram); } static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs, -- cgit v1.2.1