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greybus: loopback: timestamp seeding should not drop metrics

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In the current code if the ts variable is not initialized then any data
already gathered in a previous loopback command is dropped instead of
logged. Also the timestamping of ts is done after the greybus operation.

This delayed time-stamping means that the delta between the before and
after timestamps is incorrect and if a delay in-between loopback operations
has been specified by the user, the ts timestamp will be very skewed
indeed.

- Move the ts initialization directly before the greybus operation.
- Remove the continue statement on first initialization of the ts variable.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Bryan O'Donoghue 2015-07-21 23:50:06 +01:00 committed by Greg Kroah-Hartman
parent 09fb10fe4f
commit 3156be7dee
1 changed files with 2 additions and 4 deletions
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6
drivers/staging/greybus/loopback.c
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@ -394,6 +394,8 @@ static int gb_loopback_fn(void *data)
msleep(1000);
continue;
}
if (gb->ts.tv_usec == 0 && gb->ts.tv_sec == 0)
do_gettimeofday(&gb->ts);
if (gb->type == GB_LOOPBACK_TYPE_PING)
error = gb_loopback_ping(gb, &tlat);
else if (gb->type == GB_LOOPBACK_TYPE_TRANSFER)
@ -402,10 +404,6 @@ static int gb_loopback_fn(void *data)
error = gb_loopback_sink(gb, &tlat, gb->size);
if (error)
gb->error++;
if (gb->ts.tv_usec == 0 && gb->ts.tv_sec == 0) {
do_gettimeofday(&gb->ts);
continue;
}
do_gettimeofday(&gb->te);
gb->elapsed_nsecs = timeval_to_ns(&gb->te) -
timeval_to_ns(&gb->ts);