From 42771be625cdc4a3eada6fd42239261455e08c60 Mon Sep 17 00:00:00 2001
From: Soo-Hyun Yoo <yoos117@gmail.com>
Date: Wed, 17 Jun 2015 14:27:56 -0700
Subject: [PATCH] refs #45 Tweak buffer sizes and things.

---
 src/filesystem/filesystem.cpp       | 14 +++++++++-----
 src/filesystem/filesystem.hpp       |  5 +++++
 src/filesystem/fs_writer_thread.cpp | 19 +++++++------------
 src/filesystem/fs_writer_thread.hpp | 10 ++++++----
 src/filesystem/fs_writer_thread.tpp | 10 ++++------
 src/filesystem/logger.cpp           |  2 +-
 6 files changed, 32 insertions(+), 28 deletions(-)

diff --git a/src/filesystem/filesystem.cpp b/src/filesystem/filesystem.cpp
index bdbcb90..2fa4d86 100644
--- a/src/filesystem/filesystem.cpp
+++ b/src/filesystem/filesystem.cpp
@@ -137,18 +137,22 @@ void FileSystem::write(uint8_t *buf, uint16_t len) {
     // TODO(yoos): set FS error flag
     //chprintf(chp, "write failed\r\n");
   }
-  err = f_sync(&FileObject);   // TODO(yoos): This ensures data gets written, but bad for performance...
-  if (err != FR_OK) {
-    // TODO(yoos): set FS error flag
-    //chprintf(chp, "sync failed\r\n");
-  }
   if (bytes_written != len) {
     // TODO(yoos): set FS error flag
     //chprintf(chp, "write incomplete\r\n");
   }
+  //sync();   // TODO(yoos): This ensures data gets written, but bad for performance...
   // TODO(yoos): On failure, reset logger to wait state
 }
 
+void FileSystem::sync(void) {
+  err = f_sync(&FileObject);
+  if (err != FR_OK) {
+    // TODO(yoos): set FS error flag
+    //chprintf(chp, "sync failed\r\n");
+  }
+}
+
 void FileSystem::getFn(char *buf) {
   std::strcpy(buf, fname);
 }
diff --git a/src/filesystem/filesystem.hpp b/src/filesystem/filesystem.hpp
index 1018c45..b08b580 100644
--- a/src/filesystem/filesystem.hpp
+++ b/src/filesystem/filesystem.hpp
@@ -65,6 +65,11 @@ class FileSystem {
    */
   void write(uint8_t *c, uint16_t len);
 
+  /**
+   * Sync filesystem.
+   */
+  void sync(void);
+
   /**
    * Get short filename
    */
diff --git a/src/filesystem/fs_writer_thread.cpp b/src/filesystem/fs_writer_thread.cpp
index 52080bd..ffacca0 100644
--- a/src/filesystem/fs_writer_thread.cpp
+++ b/src/filesystem/fs_writer_thread.cpp
@@ -8,6 +8,7 @@
 FsWriterThread::FsWriterThread(SDCDriver& sdcd, Communicator& communicator)
   : fs(sdcd),
     fsInfoMessageStream(communicator, 1) {
+      rb_init(&buf, sizeof(_buf), _buf);
 }
 
 msg_t FsWriterThread::main() {
@@ -17,19 +18,14 @@ msg_t FsWriterThread::main() {
   while (!fs.connect()) chThdSleepMilliseconds(10);
   while (!fs.mount())   chThdSleepMilliseconds(10);
   while (!fs.openNew()) chThdSleepMilliseconds(10);
+  fsReady = true;
 
   while(true) {
-    // Check if there is data in the buffer that has not yet been written.
-    if(bottom != top) {
-      size_t numbytes = (top > bottom) ? top-bottom : buffer.size()-bottom;
-      fs.write(&buffer[bottom], numbytes);
-      bottom += numbytes;
-
-      // Wrap if the end of the buffer is reached.
-      if(bottom >= buffer.size()) {
-        bottom = 0;
-      }
-    }
+    uint32_t count = buf.count;
+    if (count > 3000) count = 3000 + 0.0625*(count-3000);
+    rb_remove(&buf, count, writebuf);
+    fs.write(writebuf, count);
+    fs.sync();
 
     if (fsInfoMessageStream.ready()) {
       protocol::message::fs_info_message_t m;
@@ -40,7 +36,6 @@ msg_t FsWriterThread::main() {
       fsInfoMessageStream.publish(m);
     }
 
-    // TODO(kyle): Just yield, or sleep?
     yield();
   }
 
diff --git a/src/filesystem/fs_writer_thread.hpp b/src/filesystem/fs_writer_thread.hpp
index 262b9b0..ae1a0f3 100644
--- a/src/filesystem/fs_writer_thread.hpp
+++ b/src/filesystem/fs_writer_thread.hpp
@@ -9,11 +9,12 @@
 #include "communication/communicator.hpp"
 #include "communication/rate_limited_stream.hpp"
 #include "filesystem/filesystem.hpp"
+#include "filesystem/ringbuffer.hpp"
 
 /**
  * Thread to write to storage media without blocking control thread.
  */
-class FsWriterThread : public chibios_rt::BaseStaticThread<2048> {
+class FsWriterThread : public chibios_rt::BaseStaticThread<1024> {
 public:
   FsWriterThread(SDCDriver& sdcd, Communicator& communicator);
 
@@ -27,11 +28,12 @@ class FsWriterThread : public chibios_rt::BaseStaticThread<2048> {
 
 private:
   FileSystem fs;
+  bool fsReady;
   RateLimitedStream fsInfoMessageStream;
 
-  std::array<std::uint8_t, 20000> buffer;
-  std::size_t bottom;
-  std::size_t top;
+  rb_t buf;
+  std::uint8_t _buf[83000];
+  std::uint8_t writebuf[8000];
 };
 
 #include "filesystem/fs_writer_thread.tpp"
diff --git a/src/filesystem/fs_writer_thread.tpp b/src/filesystem/fs_writer_thread.tpp
index 2f02b57..d8d299c 100644
--- a/src/filesystem/fs_writer_thread.tpp
+++ b/src/filesystem/fs_writer_thread.tpp
@@ -1,10 +1,8 @@
+#include <chprintf.h>
+
 template <std::size_t size>
 void FsWriterThread::append(std::array<std::uint8_t, size> ap, std::size_t len) {
-  for(std::size_t i = 0; i < len; i++) {
-    buffer[top++] = ap[i];
-
-    if(top >= buffer.size()) {
-      top = 0;
-    }
+  if (fsReady) {
+    rb_add(&buf, len, ap.data());
   }
 }
diff --git a/src/filesystem/logger.cpp b/src/filesystem/logger.cpp
index b23a517..f2ae83a 100644
--- a/src/filesystem/logger.cpp
+++ b/src/filesystem/logger.cpp
@@ -9,7 +9,7 @@ void Logger::start(void) {
   // TODO(yoos): Rethink this, as in the rocket, we really want to log data
   // before we transmit to ground, but this is not the case in radio-controlled
   // vehicles. Maybe priorities should be user-configurable.
-  writer.start(LOWPRIO + 2);
+  writer.start(HIGHPRIO-1);
 }
 
 bool Logger::ready(void) {