chore: update e2e-fio

Regularise command enum members (do not mix with #defines)
Update comments in e2e-fio.c for clarity
Updated readme
bump version number as code has changed a tuiny bit

Signed-off-by: Blaise Dias <[email protected]>

Author: Blaise Dias

common/e2e_config/e2e_config.go

@@ -208,7 +208,7 @@ type E2EConfig struct {
 	InstallLoki                  bool   `yaml:"installLoki" env-default:"true" env:"install_loki"`
 	InstallHaModeEtcd            bool   `yaml:"installHaModeEtcd" env-default:"false" env:"e2e_etcd_ha_mode"`
 	LokiStatefulsetOnControlNode bool   `yaml:"lokiOnControlNode" env-default:"true" env:"loki_on_control_node"`
-	E2eFioImage                  string `yaml:"e2eFioImage" env-default:"openebs/e2e-fio:v3.38-e2e-0" env:"e2e_fio_image"`
+	E2eFioImage                  string `yaml:"e2eFioImage" env-default:"openebs/e2e-fio:v3.38-e2e-1" env:"e2e_fio_image"`
 	SetSafeMountAlways           bool   `yaml:"setSafeMountAlways" env-default:"false" env:"safe_mount_always"`
 	// This is an advisory setting for individual tests
 	// If set to true - typically during test development - tests with multiple 'It' clauses should defer asserts till after

tools/e2e-fio/README.md

@@ -1,6 +1,11 @@
-# Mayastor E2E fio test pod
+# Mayastor E2E fio test pod image
 ## Introduction
-Derived from `dmonakhov/alpine-fio`
+This image is derived from `alpine`
+
+It includes fio, which is invoked by the wrapper program `e2e_fio`
+
+e2e_fio is written in C to facilitate low level control and to keep the size small.
+Reduced size makes it possible to run more instances of the test pod with a given memory constraint.
 
 ### Command line options
  * `sleep <sleep seconds> ;`
@@ -41,8 +46,6 @@ Thus allows developer to exec a shell on the pod and examine the pod.
 
 Execution will only complete after all forked processes (if any) have completed as well as inline sleep and signal generation actions.
 
-For legacy compatibility where implicit start of a new option is detected
-
 ### Exit value
  * If `exitv` is specified that is *always* returned.
  * 0 if all instances of forked processes ran successfully exit value is 0

tools/e2e-fio/build.sh

@@ -11,7 +11,7 @@
 # existing semantics.
 set -e
 IMAGE="openebs/e2e-fio"
-TAG="v3.38-e2e-0"
+TAG="v3.38-e2e-1"
 registry=""
 tag_as_latest=""