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greybus: loopback: remove redundant timestamping 

It is of more interest to graphing system performance to base our
timestamps on the time it takes a greybus_operation_sync() to complete.
Higher level timestamping code is less accurate and not relevant to
throughput and latency characterization.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
hifive-unleashed-5.1
Bryan O'Donoghue 2015-07-28 18:34:35 +01:00 committed by Greg Kroah-Hartman
parent 9612f2bcd4
commit a7e60062b0
1 changed files with 11 additions and 30 deletions
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41
drivers/staging/greybus/loopback.c
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@ -43,8 +43,6 @@ struct gb_loopback {
struct gb_loopback_stats latency;
struct gb_loopback_stats throughput;
struct gb_loopback_stats requests_per_second;
struct timeval ts;
struct timeval te;
u64 elapsed_nsecs;
u32 error;
};
@ -180,11 +178,9 @@ static struct attribute *loopback_attrs[] = {
};
ATTRIBUTE_GROUPS(loopback);
static int gb_loopback_sink(struct gb_loopback *gb,
struct timeval *tping, u32 len)
static int gb_loopback_sink(struct gb_loopback *gb, u32 len)
{
struct timeval ts, te;
u64 elapsed_nsecs;
struct gb_loopback_transfer_request *request;
int retval;
@ -199,18 +195,15 @@ static int gb_loopback_sink(struct gb_loopback *gb,
request, len + sizeof(*request), NULL, 0);
do_gettimeofday(&te);
elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
*tping = ns_to_timeval(elapsed_nsecs);
gb->elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
kfree(request);
return retval;
}
static int gb_loopback_transfer(struct gb_loopback *gb,
struct timeval *tping, u32 len)
static int gb_loopback_transfer(struct gb_loopback *gb, u32 len)
{
struct timeval ts, te;
u64 elapsed_nsecs;
struct gb_loopback_transfer_request *request;
struct gb_loopback_transfer_response *response;
int retval;
@ -231,8 +224,7 @@ static int gb_loopback_transfer(struct gb_loopback *gb,
request, len + sizeof(*request),
response, len + sizeof(*response));
do_gettimeofday(&te);
elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
*tping = ns_to_timeval(elapsed_nsecs);
gb->elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
if (retval)
goto gb_error;
@ -247,18 +239,16 @@ gb_error:
return retval;
}
static int gb_loopback_ping(struct gb_loopback *gb, struct timeval *tping)
static int gb_loopback_ping(struct gb_loopback *gb)
{
struct timeval ts, te;
u64 elapsed_nsecs;
int retval;
do_gettimeofday(&ts);
retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_PING,
NULL, 0, NULL, 0);
do_gettimeofday(&te);
elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
*tping = ns_to_timeval(elapsed_nsecs);
gb->elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts);
return retval;
}
@ -324,7 +314,6 @@ static void gb_loopback_reset_stats(struct gb_loopback *gb)
memcpy(&gb->throughput, &reset, sizeof(struct gb_loopback_stats));
memcpy(&gb->requests_per_second, &reset,
sizeof(struct gb_loopback_stats));
memset(&gb->ts, 0, sizeof(struct timeval));
}
static void gb_loopback_update_stats(struct gb_loopback_stats *stats, u64 val)
@ -375,8 +364,7 @@ static void gb_loopback_throughput_update(struct gb_loopback *gb, u32 latency)
gb_loopback_update_stats(&gb->throughput, throughput);
}
static void gb_loopback_calculate_stats(struct gb_loopback *gb,
struct timeval *tlat)
static void gb_loopback_calculate_stats(struct gb_loopback *gb)
{
u32 lat;
u64 tmp;
@ -397,7 +385,6 @@ static void gb_loopback_calculate_stats(struct gb_loopback *gb,
static int gb_loopback_fn(void *data)
{
int error = 0;
struct timeval tlat = {0, 0};
struct gb_loopback *gb = (struct gb_loopback *)data;
while (1) {
@ -416,21 +403,15 @@ static int gb_loopback_fn(void *data)
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);
error = gb_loopback_ping(gb);
else if (gb->type == GB_LOOPBACK_TYPE_TRANSFER)
error = gb_loopback_transfer(gb, &tlat, gb->size);
error = gb_loopback_transfer(gb, gb->size);
else if (gb->type == GB_LOOPBACK_TYPE_SINK)
error = gb_loopback_sink(gb, &tlat, gb->size);
error = gb_loopback_sink(gb, gb->size);
if (error)
gb->error++;
do_gettimeofday(&gb->te);
gb->elapsed_nsecs = timeval_to_ns(&gb->te) -
timeval_to_ns(&gb->ts);
gb_loopback_calculate_stats(gb, &tlat);
gb->ts = gb->te;
gb_loopback_calculate_stats(gb);
if (gb->ms_wait)
msleep(gb->ms_wait);
}