selftests/ftrace: Support ":tracer" suffix for requires

Add ":tracer" suffix support for the requires list, so that
the testcase can list up the required tracer (e.g. function)
to the requires list.

For example, if the testcase requires function_graph tracer,
it can write requires list as below instead of checking
available_tracers.

# requires: function_graph:tracer
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function graph filters with stack tracer
-# requires: stack_trace set_ftrace_filter
+# requires: stack_trace set_ftrace_filter function_graph:tracer
 
 # Make sure that function graph filtering works, and is not
 # affected by other tracers enabled (like stack tracer)
 
-if ! grep -q function_graph available_tracers; then
-    echo "no function graph tracer configured"
-    exit_unsupported
-fi
-
 do_reset() {
     if [ -e /proc/sys/kernel/stack_tracer_enabled ]; then
 	    echo 0 > /proc/sys/kernel/stack_tracer_enabled

tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function graph filters
-# requires: set_ftrace_filter
+# requires: set_ftrace_filter function_graph:tracer
 
 # Make sure that function graph filtering works
 
-if ! grep -q function_graph available_tracers; then
-    echo "no function graph tracer configured"
-    exit_unsupported
-fi
-
 fail() { # msg
     echo $1
     exit_fail

tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function glob filters
-# requires: set_ftrace_filter
+# requires: set_ftrace_filter function:tracer
 
 # Make sure that function glob matching filter works.
 
-if ! grep -q function available_tracers; then
-    echo "no function tracer configured"
-    exit_unsupported
-fi
-
 disable_tracing
 clear_trace
 

tools/testing/selftests/ftrace/test.d/ftrace/func-filter-notrace-pid.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function pid notrace filters
-# requires: set_ftrace_notrace_pid set_ftrace_filter
+# requires: set_ftrace_notrace_pid set_ftrace_filter function:tracer
 # flags: instance
 
 # Make sure that function pid matching filter with notrace works.
 
-if ! grep -q function available_tracers; then
-    echo "no function tracer configured"
-    exit_unsupported
-fi
-
 do_function_fork=1
 
 if [ ! -f options/function-fork ]; then

tools/testing/selftests/ftrace/test.d/ftrace/func-filter-pid.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function pid filters
-# requires: set_ftrace_pid set_ftrace_filter
+# requires: set_ftrace_pid set_ftrace_filter function:tracer
 # flags: instance
 
 # Make sure that function pid matching filter works.
 # Also test it on an instance directory
 
-if ! grep -q function available_tracers; then
-    echo "no function tracer configured"
-    exit_unsupported
-fi
-
 do_function_fork=1
 
 if [ ! -f options/function-fork ]; then

tools/testing/selftests/ftrace/test.d/ftrace/func_cpumask.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function trace with cpumask
+# requires: function:tracer
 
 if ! which nproc ; then
   nproc() {
@@ -15,11 +16,6 @@ if [ $NP -eq 1 ] ;then
   exit_unresolved
 fi
 
-if ! grep -q "function" available_tracers ; then
-  echo "Function trace is not enabled"
-  exit_unsupported
-fi
-
 ORIG_CPUMASK=`cat tracing_cpumask`
 
 do_reset() {

tools/testing/selftests/ftrace/test.d/ftrace/func_profiler.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: ftrace - function profiler with function tracing
-# requires: function_profile_enabled set_ftrace_filter
+# requires: function_profile_enabled set_ftrace_filter function_graph:tracer
 
 # There was a bug after a rewrite of the ftrace infrastructure that
 # caused the function_profiler not to be able to run with the function
@@ -14,10 +14,6 @@
 # This test triggers those bugs on those kernels.
 #
 # We need function_graph and profiling to to run this test
-if ! grep -q function_graph available_tracers; then
-    echo "no function graph tracer configured"
-    exit_unsupported;
-fi
 
 fail() { # mesg
     echo $1

tools/testing/selftests/ftrace/test.d/functions

@@ -106,9 +106,15 @@ initialize_ftrace() { # Reset ftrace to initial-state
     enable_tracing
 }
 
-check_requires() { # Check required files
+check_requires() { # Check required files and tracers
     for i in $* ; do
-        if [ ! -e $i ]; then
+        t=${i%:tracer}
+        if [ $t != $i ]; then
+            if ! grep -wq $t available_tracers ; then
+                echo "Required tracer $t is not configured."
+                exit_unsupported
+            fi
+        elif [ ! -e $i ]; then
             echo "Required feature interface $i doesn't exist."
             exit_unsupported
         fi

tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: Kprobe dynamic event with function tracer
-# requires: kprobe_events stack_trace_filter
-
-grep "function" available_tracers || exit_unsupported # this is configurable
+# requires: kprobe_events stack_trace_filter function:tracer
 
 # prepare
 echo nop > current_tracer

tools/testing/selftests/ftrace/test.d/preemptirq/irqsoff_tracer.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: test for the preemptirqsoff tracer
+# requires: preemptoff:tracer irqsoff:tracer
 
 MOD=preemptirq_delay_test
 
@@ -27,9 +28,6 @@ unres() { #msg
 modprobe $MOD || unres "$MOD module not available"
 rmmod $MOD
 
-grep -q "preemptoff" available_tracers || unsup "preemptoff tracer not enabled"
-grep -q "irqsoff" available_tracers || unsup "irqsoff tracer not enabled"
-
 reset_tracer
 
 # Simulate preemptoff section for half a second couple of times

tools/testing/selftests/ftrace/test.d/template

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: %HERE DESCRIBE WHAT THIS DOES%
-# requires: %HERE LIST THE REQUIRED FILES%
+# requires: %HERE LIST THE REQUIRED FILES OR TRACERS%
+# The required tracer needs :tracer suffix, e.g. function:tracer
 # you have to add ".tc" extention for your testcase file
 # Note that all tests are run with "errexit" option.
 

tools/testing/selftests/ftrace/test.d/tracer/wakeup.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: Test wakeup tracer
+# requires: wakeup:tracer
 
 if ! which chrt ; then
   echo "chrt is not found. This test requires nice command."
   exit_unresolved
 fi
 
-if ! grep -wq "wakeup" available_tracers ; then
-  echo "wakeup tracer is not supported"
-  exit_unsupported
-fi
-
 echo wakeup > current_tracer
 echo 1 > tracing_on
 echo 0 > tracing_max_latency

tools/testing/selftests/ftrace/test.d/tracer/wakeup_rt.tc

 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 # description: Test wakeup RT tracer
+# requires: wakeup_rt:tracer
 
 if ! which chrt ; then
   echo "chrt is not found. This test requires chrt command."
   exit_unresolved
 fi
 
-if ! grep -wq "wakeup_rt" available_tracers ; then
-  echo "wakeup_rt tracer is not supported"
-  exit_unsupported
-fi
-
 echo wakeup_rt > current_tracer
 echo 1 > tracing_on
 echo 0 > tracing_max_latency