* QEMU System Emulator block accounting
*
* Copyright (c) 2011 Christoph Hellwig
+ * Copyright (c) 2015 Igalia, S.L.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* THE SOFTWARE.
*/
+#include "qemu/osdep.h"
#include "block/accounting.h"
#include "block/block_int.h"
#include "qemu/timer.h"
+#include "sysemu/qtest.h"
static QEMUClockType clock_type = QEMU_CLOCK_REALTIME;
+static const int qtest_latency_ns = NANOSECONDS_PER_SECOND / 1000;
-void block_acct_init(BlockAcctStats *stats, bool account_invalid,
- bool account_failed)
+void block_acct_init(BlockAcctStats *stats)
+{
+ qemu_mutex_init(&stats->lock);
+ if (qtest_enabled()) {
+ clock_type = QEMU_CLOCK_VIRTUAL;
+ }
+}
+
+void block_acct_setup(BlockAcctStats *stats, bool account_invalid,
+ bool account_failed)
{
stats->account_invalid = account_invalid;
stats->account_failed = account_failed;
}
+void block_acct_cleanup(BlockAcctStats *stats)
+{
+ BlockAcctTimedStats *s, *next;
+ QSLIST_FOREACH_SAFE(s, &stats->intervals, entries, next) {
+ g_free(s);
+ }
+ qemu_mutex_destroy(&stats->lock);
+}
+
+void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length)
+{
+ BlockAcctTimedStats *s;
+ unsigned i;
+
+ s = g_new0(BlockAcctTimedStats, 1);
+ s->interval_length = interval_length;
+ s->stats = stats;
+ qemu_mutex_lock(&stats->lock);
+ QSLIST_INSERT_HEAD(&stats->intervals, s, entries);
+
+ for (i = 0; i < BLOCK_MAX_IOTYPE; i++) {
+ timed_average_init(&s->latency[i], clock_type,
+ (uint64_t) interval_length * NANOSECONDS_PER_SECOND);
+ }
+ qemu_mutex_unlock(&stats->lock);
+}
+
+BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats,
+ BlockAcctTimedStats *s)
+{
+ if (s == NULL) {
+ return QSLIST_FIRST(&stats->intervals);
+ } else {
+ return QSLIST_NEXT(s, entries);
+ }
+}
+
void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
int64_t bytes, enum BlockAcctType type)
{
cookie->type = type;
}
-void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
+/* block_latency_histogram_compare_func:
+ * Compare @key with interval [@it[0], @it[1]).
+ * Return: -1 if @key < @it[0]
+ * 0 if @key in [@it[0], @it[1])
+ * +1 if @key >= @it[1]
+ */
+static int block_latency_histogram_compare_func(const void *key, const void *it)
{
- int64_t time_ns = qemu_clock_get_ns(clock_type);
- int64_t latency_ns = time_ns - cookie->start_time_ns;
+ uint64_t k = *(uint64_t *)key;
+ uint64_t a = ((uint64_t *)it)[0];
+ uint64_t b = ((uint64_t *)it)[1];
+
+ return k < a ? -1 : (k < b ? 0 : 1);
+}
+
+static void block_latency_histogram_account(BlockLatencyHistogram *hist,
+ int64_t latency_ns)
+{
+ uint64_t *pos;
+
+ if (hist->bins == NULL) {
+ /* histogram disabled */
+ return;
+ }
- assert(cookie->type < BLOCK_MAX_IOTYPE);
- stats->nr_bytes[cookie->type] += cookie->bytes;
- stats->nr_ops[cookie->type]++;
- stats->total_time_ns[cookie->type] += latency_ns;
- stats->last_access_time_ns = time_ns;
+ if (latency_ns < hist->boundaries[0]) {
+ hist->bins[0]++;
+ return;
+ }
+
+ if (latency_ns >= hist->boundaries[hist->nbins - 2]) {
+ hist->bins[hist->nbins - 1]++;
+ return;
+ }
+
+ pos = bsearch(&latency_ns, hist->boundaries, hist->nbins - 2,
+ sizeof(hist->boundaries[0]),
+ block_latency_histogram_compare_func);
+ assert(pos != NULL);
+
+ hist->bins[pos - hist->boundaries + 1]++;
}
-void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie)
+int block_latency_histogram_set(BlockAcctStats *stats, enum BlockAcctType type,
+ uint64List *boundaries)
{
+ BlockLatencyHistogram *hist = &stats->latency_histogram[type];
+ uint64List *entry;
+ uint64_t *ptr;
+ uint64_t prev = 0;
+ int new_nbins = 1;
+
+ for (entry = boundaries; entry; entry = entry->next) {
+ if (entry->value <= prev) {
+ return -EINVAL;
+ }
+ new_nbins++;
+ prev = entry->value;
+ }
+
+ hist->nbins = new_nbins;
+ g_free(hist->boundaries);
+ hist->boundaries = g_new(uint64_t, hist->nbins - 1);
+ for (entry = boundaries, ptr = hist->boundaries; entry;
+ entry = entry->next, ptr++)
+ {
+ *ptr = entry->value;
+ }
+
+ g_free(hist->bins);
+ hist->bins = g_new0(uint64_t, hist->nbins);
+
+ return 0;
+}
+
+void block_latency_histograms_clear(BlockAcctStats *stats)
+{
+ int i;
+
+ for (i = 0; i < BLOCK_MAX_IOTYPE; i++) {
+ BlockLatencyHistogram *hist = &stats->latency_histogram[i];
+ g_free(hist->bins);
+ g_free(hist->boundaries);
+ memset(hist, 0, sizeof(*hist));
+ }
+}
+
+static void block_account_one_io(BlockAcctStats *stats, BlockAcctCookie *cookie,
+ bool failed)
+{
+ BlockAcctTimedStats *s;
+ int64_t time_ns = qemu_clock_get_ns(clock_type);
+ int64_t latency_ns = time_ns - cookie->start_time_ns;
+
+ if (qtest_enabled()) {
+ latency_ns = qtest_latency_ns;
+ }
+
assert(cookie->type < BLOCK_MAX_IOTYPE);
- stats->failed_ops[cookie->type]++;
+ qemu_mutex_lock(&stats->lock);
+
+ if (failed) {
+ stats->failed_ops[cookie->type]++;
+ } else {
+ stats->nr_bytes[cookie->type] += cookie->bytes;
+ stats->nr_ops[cookie->type]++;
+ }
- if (stats->account_failed) {
- int64_t time_ns = qemu_clock_get_ns(clock_type);
- int64_t latency_ns = time_ns - cookie->start_time_ns;
+ block_latency_histogram_account(&stats->latency_histogram[cookie->type],
+ latency_ns);
+ if (!failed || stats->account_failed) {
stats->total_time_ns[cookie->type] += latency_ns;
stats->last_access_time_ns = time_ns;
+
+ QSLIST_FOREACH(s, &stats->intervals, entries) {
+ timed_average_account(&s->latency[cookie->type], latency_ns);
+ }
}
+
+ qemu_mutex_unlock(&stats->lock);
+}
+
+void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
+{
+ block_account_one_io(stats, cookie, false);
+}
+
+void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie)
+{
+ block_account_one_io(stats, cookie, true);
}
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. */
-
+ /* block_account_one_io() updates 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.
+ */
+ qemu_mutex_lock(&stats->lock);
stats->invalid_ops[type]++;
if (stats->account_invalid) {
stats->last_access_time_ns = qemu_clock_get_ns(clock_type);
}
+ qemu_mutex_unlock(&stats->lock);
}
void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
int num_requests)
{
assert(type < BLOCK_MAX_IOTYPE);
+
+ qemu_mutex_lock(&stats->lock);
stats->merged[type] += num_requests;
+ qemu_mutex_unlock(&stats->lock);
}
int64_t block_acct_idle_time_ns(BlockAcctStats *stats)
{
return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns;
}
+
+double block_acct_queue_depth(BlockAcctTimedStats *stats,
+ enum BlockAcctType type)
+{
+ uint64_t sum, elapsed;
+
+ assert(type < BLOCK_MAX_IOTYPE);
+
+ qemu_mutex_lock(&stats->stats->lock);
+ sum = timed_average_sum(&stats->latency[type], &elapsed);
+ qemu_mutex_unlock(&stats->stats->lock);
+
+ return (double) sum / elapsed;
+}
projects / qemu.git / blobdiff