profcollectd: logging trace provider

Provide a logging trace provider that does nothing but log all trigger
events, for development and for testing on unsupported devices. This is
disabled by default, turn on "test" feature to enable.

Test: build
Bug: 194155753
Change-Id: I3377979d5a4298065b326da355908db0a3375f18
Merged-In: I3377979d5a4298065b326da355908db0a3375f18
(cherry picked from commit 8c59b8fc5398c350888dde7ff2a50912387fa9b1)

5 files changed, 82 insertions, 10 deletions

diff --git a/profcollectd/libprofcollectd/Android.bp b/profcollectd/libprofcollectd/Android.bp
index 2e37af9e..7fb1b567 100644
--- a/profcollectd/libprofcollectd/Android.bp
+++ b/profcollectd/libprofcollectd/Android.bp
@@ -60,4 +60,7 @@ rust_library {
         "libsimpleperf_profcollect_rust",
     ],
     shared_libs: ["libsimpleperf_profcollect"],
+
+    // Enable 'test' feature for more verbose logging and the logging trace provider.
+    // features: ["test"],
 }
diff --git a/profcollectd/libprofcollectd/lib.rs b/profcollectd/libprofcollectd/lib.rs
index aacbf8e3..f417bd8c 100644
--- a/profcollectd/libprofcollectd/lib.rs
+++ b/profcollectd/libprofcollectd/lib.rs
@@ -23,6 +23,9 @@ mod service;
 mod simpleperf_etm_trace_provider;
 mod trace_provider;
 
+#[cfg(feature = "test")]
+mod logging_trace_provider;
+
 use anyhow::{Context, Result};
 use profcollectd_aidl_interface::aidl::com::android::server::profcollect::IProfCollectd::{
     self, BnProfCollectd,
@@ -90,9 +93,8 @@ pub fn report() -> Result<String> {
 
 /// Inits logging for Android
 pub fn init_logging() {
+    let min_log_level = if cfg!(feature = "test") { log::Level::Info } else { log::Level::Error };
     android_logger::init_once(
-        android_logger::Config::default()
-            .with_tag("profcollectd")
-            .with_min_level(log::Level::Error),
+        android_logger::Config::default().with_tag("profcollectd").with_min_level(min_log_level),
     );
 }
diff --git a/profcollectd/libprofcollectd/logging_trace_provider.rs b/profcollectd/libprofcollectd/logging_trace_provider.rs
new file mode 100644
index 00000000..1325855d
--- /dev/null
+++ b/profcollectd/libprofcollectd/logging_trace_provider.rs
@@ -0,0 +1,56 @@
+//
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+//! Logging trace provider for development and testing purposes.
+
+use anyhow::Result;
+use std::path::Path;
+use std::time::Duration;
+use trace_provider::TraceProvider;
+
+use crate::trace_provider;
+
+static LOGGING_TRACEFILE_EXTENSION: &str = "loggingtrace";
+
+pub struct LoggingTraceProvider {}
+
+impl TraceProvider for LoggingTraceProvider {
+    fn get_name(&self) -> &'static str {
+        "logging"
+    }
+
+    fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration) {
+        let trace_file = trace_provider::get_path(trace_dir, tag, LOGGING_TRACEFILE_EXTENSION);
+
+        log::info!(
+            "Trace event triggered, tag {}, sampling for {}ms, saving to {}",
+            tag,
+            sampling_period.as_millis(),
+            trace_file.display()
+        );
+    }
+
+    fn process(&self, _trace_dir: &Path, _profile_dir: &Path) -> Result<()> {
+        log::info!("Process event triggered");
+        Ok(())
+    }
+}
+
+impl LoggingTraceProvider {
+    pub fn supported() -> bool {
+        true
+    }
+}
diff --git a/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs b/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
index 2038a5be..d3baaa36 100644
--- a/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
+++ b/profcollectd/libprofcollectd/simpleperf_etm_trace_provider.rs
@@ -35,12 +35,10 @@ impl TraceProvider for SimpleperfEtmTraceProvider {
     }
 
     fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration) {
-        let mut trace_file = PathBuf::from(trace_dir);
-        trace_file.push(trace_provider::construct_file_name(tag));
-        trace_file.set_extension(ETM_TRACEFILE_EXTENSION);
+        let trace_file = trace_provider::get_path(trace_dir, tag, ETM_TRACEFILE_EXTENSION);
 
         simpleperf_profcollect::record(
-            &trace_file,
+            &*trace_file,
             sampling_period,
             simpleperf_profcollect::RecordScope::BOTH,
         );
diff --git a/profcollectd/libprofcollectd/trace_provider.rs b/profcollectd/libprofcollectd/trace_provider.rs
index ed0d56f5..44d4cee9 100644
--- a/profcollectd/libprofcollectd/trace_provider.rs
+++ b/profcollectd/libprofcollectd/trace_provider.rs
@@ -18,12 +18,15 @@
 
 use anyhow::{anyhow, Result};
 use chrono::Utc;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
 use crate::simpleperf_etm_trace_provider::SimpleperfEtmTraceProvider;
 
+#[cfg(feature = "test")]
+use crate::logging_trace_provider::LoggingTraceProvider;
+
 pub trait TraceProvider {
     fn get_name(&self) -> &'static str;
     fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration);
@@ -36,9 +39,19 @@ pub fn get_trace_provider() -> Result<Arc<Mutex<dyn TraceProvider + Send>>> {
         return Ok(Arc::new(Mutex::new(SimpleperfEtmTraceProvider {})));
     }
 
+    #[cfg(feature = "test")]
+    if LoggingTraceProvider::supported() {
+        log::info!("logging trace provider registered.");
+        return Ok(Arc::new(Mutex::new(LoggingTraceProvider {})));
+    }
+
     Err(anyhow!("No trace provider found for this device."))
 }
 
-pub fn construct_file_name(tag: &str) -> String {
-    format!("{}_{}", Utc::now().format("%Y%m%d-%H%M%S"), tag)
+pub fn get_path(dir: &Path, tag: &str, ext: &str) -> Box<Path> {
+    let filename = format!("{}_{}", Utc::now().format("%Y%m%d-%H%M%S"), tag);
+    let mut trace_file = PathBuf::from(dir);
+    trace_file.push(filename);
+    trace_file.set_extension(ext);
+    trace_file.into_boxed_path()
 }