On Mon, 2023-05-15 at 21:56 +0200, Juan Quintela wrote:
> It is a time that needs to be cleaned each time cancel migration.
> Once there create migration_time_since() to calculate how time since a
> time in the past.
>
> Signed-off-by: Juan Quintela <quint...@redhat.com>
>
> ---
>
> Rename to migration_time_since (cédric)
> ---
> migration/migration-stats.h | 13 +++++++++++++
> migration/migration.h | 1 -
> migration/migration-stats.c | 7 +++++++
> migration/migration.c | 9 ++++-----
> 4 files changed, 24 insertions(+), 6 deletions(-)
>
> diff --git a/migration/migration-stats.h b/migration/migration-stats.h
> index e782f1b0df..21402af9e4 100644
> --- a/migration/migration-stats.h
> +++ b/migration/migration-stats.h
> @@ -75,6 +75,10 @@ typedef struct {
> * Number of bytes sent during precopy stage.
> */
> Stat64 precopy_bytes;
> + /*
> + * How long has the setup stage took.
> + */
> + Stat64 setup_time;
> /*
> * Total number of bytes transferred.
> */
> @@ -87,4 +91,13 @@ typedef struct {
>
> extern MigrationAtomicStats mig_stats;
>
> +/**
> + * migration_time_since: Calculate how much time has passed
> + *
> + * @stats: migration stats
> + * @since: reference time since we want to calculate
> + *
> + * Returns: Nothing. The time is stored in val.
> + */
> +void migration_time_since(MigrationAtomicStats *stats, int64_t since);
> #endif
> diff --git a/migration/migration.h b/migration/migration.h
> index 48a46123a0..27aa3b1035 100644
> --- a/migration/migration.h
> +++ b/migration/migration.h
> @@ -316,7 +316,6 @@ struct MigrationState {
> int64_t downtime;
> int64_t expected_downtime;
> bool capabilities[MIGRATION_CAPABILITY__MAX];
> - int64_t setup_time;
> /*
> * Whether guest was running when we enter the completion stage.
> * If migration is interrupted by any reason, we need to continue
> diff --git a/migration/migration-stats.c b/migration/migration-stats.c
> index 2f2cea965c..3431453c90 100644
> --- a/migration/migration-stats.c
> +++ b/migration/migration-stats.c
> @@ -12,6 +12,13 @@
>
> #include "qemu/osdep.h"
> #include "qemu/stats64.h"
> +#include "qemu/timer.h"
> #include "migration-stats.h"
>
> MigrationAtomicStats mig_stats;
> +
> +void migration_time_since(MigrationAtomicStats *stats, int64_t since)
> +{
> + int64_t now = qemu_clock_get_ms(QEMU_CLOCK_HOST);
> + stat64_set(&stats->setup_time, now - since);
> +}
IIUC this calculates a time delta and saves on stats->setup_time, is that right?
It took me some time to understand that, since the function name is
migration_time_since(), which seems more generic.
Would not be more intuitive to name it migration_setup_time_set() or so?
Anyway,
Reviewed-by: Leonardo Bras <leob...@redhat.com>
> diff --git a/migration/migration.c b/migration/migration.c
> index c41c7491bb..e9466273bb 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -887,7 +887,7 @@ static void populate_time_info(MigrationInfo *info,
> MigrationState *s)
> {
> info->has_status = true;
> info->has_setup_time = true;
> - info->setup_time = s->setup_time;
> + info->setup_time = stat64_get(&mig_stats.setup_time);
>
> if (s->state == MIGRATION_STATUS_COMPLETED) {
> info->has_total_time = true;
> @@ -1390,7 +1390,6 @@ void migrate_init(MigrationState *s)
> s->pages_per_second = 0.0;
> s->downtime = 0;
> s->expected_downtime = 0;
> - s->setup_time = 0;
I could not see MigrationState->setup_time being initialized as 0 in this patch.
In a quick look in the code I noticed there is no initialization of this struct,
but on qemu_savevm_state() and migrate_prepare() we have:
memset(&mig_stats, 0, sizeof(mig_stats));
I suppose this is enough, right?
> s->start_postcopy = false;
> s->postcopy_after_devices = false;
> s->migration_thread_running = false;
> @@ -2647,7 +2646,7 @@ static void migration_calculate_complete(MigrationState
> *s)
> s->downtime = end_time - s->downtime_start;
> }
>
> - transfer_time = s->total_time - s->setup_time;
> + transfer_time = s->total_time - stat64_get(&mig_stats.setup_time);
> if (transfer_time) {
> s->mbps = ((double) bytes * 8.0) / transfer_time / 1000;
> }
> @@ -2969,7 +2968,7 @@ static void *migration_thread(void *opaque)
> qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP,
> MIGRATION_STATUS_ACTIVE);
>
> - s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
> + migration_time_since(&mig_stats, setup_start);
>
> trace_migration_thread_setup_complete();
>
> @@ -3081,7 +3080,7 @@ static void *bg_migration_thread(void *opaque)
> qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP,
> MIGRATION_STATUS_ACTIVE);
>
> - s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
> + migration_time_since(&mig_stats, setup_start);
>
> trace_migration_thread_setup_complete();
> s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
