greybus: loopback: provide interface to read all latency data-points

Browse source

The current loopback code provides the minimum, maximum and average latency
values for a given test set. It would be highly useful for user-space to
have access to each one of the latency metrics in order to graph outliers.

This patch adds a simple character device interface implmenting a read()
interface that allows user-space to read out the saved latency metrics
which have been stored in a kfifo for this purpose.

A module parameter is provided to allow varying the depth of the kfifo in
order to allow a user to capture potentially large data sets. This version
sets the default depth for the kfifo at 8192 dwords.

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 2015-07-28 18:34:38 +01:00 • committed by Greg Kroah-Hartman

parent 85d678c0be

commit cbd204b48d

1 changed files with 143 additions and 3 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

146

drivers/staging/greybus/loopback.c

View file