cottongin/crosspoint-reader-mod
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

refactor: move render() to Activity super class, use freeRTOS notification (#774)

Browse Source 
## Summary

Currently, each activity has to manage their own `displayTaskLoop` which
adds redundant boilerplate code. The loop is a wait loop which is also
not the best practice, as the `updateRequested` boolean is not protected
by a mutex.

In this PR:
- Move `displayTaskLoop` to the super `Activity` class
- Replace `updateRequested` with freeRTOS's [direct to task
notification](https://www.freertos.org/Documentation/02-Kernel/02-Kernel-features/03-Direct-to-task-notifications/01-Task-notifications)
- For `ActivityWithSubactivity`, whenever a sub-activity is present, the
parent's `render()` automatically goes inactive

With this change, activities now only need to expose `render()`
function, and anywhere in the code base can call `requestUpdate()` to
request a new rendering pass.

## Additional Context

In theory, this change may also make the battery life a bit better,
since one wait loop is removed. Although the equipment in my home lab
wasn't been able to verify it (the electric current is too noisy and
small). Would appreciate if anyone has any insights on this subject.

Update: I managed to hack [a small piece of
code](https://github.com/ngxson/crosspoint-reader/tree/xsn/measure_cpu_usage)
that allow tracking CPU idle time.

The CPU load does decrease a bit (1.47% down to 1.39%), which make
sense, because the display task is now sleeping most of the time unless
notified. This should translate to a slightly increase in battery life
in the long run.

```
PR:
[40012] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[40012] [IDLE] Idle time: 98.61% (CPU load: 1.39%)
[50017] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[50017] [IDLE] Idle time: 98.61% (CPU load: 1.39%)
[60022] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[60022] [IDLE] Idle time: 98.61% (CPU load: 1.39%)

master:
[20012] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[20012] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
[30017] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[30017] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
[40022] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[40022] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
```

---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? **NO**


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Refactor**
* Streamlined rendering architecture by consolidating update mechanisms
across all activities, improving efficiency and consistency.
* Modernized synchronization patterns for display updates to ensure
reliable, conflict-free rendering.

* **Bug Fixes**
* Enhanced rendering stability through improved locking mechanisms and
explicit update requests.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: znelson <znelson@users.noreply.github.com>
This commit is contained in:
Xuan-Son Nguyen
2026-02-16 11:11:15 +01:00
committed by GitHub
parent 0508bfc1f7
commit a616f42cb4
53 changed files with 458 additions and 1409 deletions
Download Patch File Download Diff File Expand all files Collapse all files

49
src/activities/home/HomeActivity.cpp
View File

@@ -19,11 +19,6 @@
#include "fontIds.h"
#include "util/StringUtils.h"
void HomeActivity::taskTrampoline(void* param) {
auto* self = static_cast<HomeActivity*>(param);
self->displayTaskLoop();
}
int HomeActivity::getMenuItemCount() const {
int count = 4; // My Library, Recents, File transfer, Settings
if (!recentBooks.empty()) {
@@ -83,7 +78,7 @@ void HomeActivity::loadRecentCovers(int coverHeight) {
book.coverBmpPath = "";
}
coverRendered = false;
updateRequired = true;
requestUpdate();
} else if (StringUtils::checkFileExtension(book.path, ".xtch") ||
StringUtils::checkFileExtension(book.path, ".xtc")) {
// Handle XTC file
@@ -101,7 +96,7 @@ void HomeActivity::loadRecentCovers(int coverHeight) {
book.coverBmpPath = "";
}
coverRendered = false;
updateRequired = true;
requestUpdate();
}
}
}
@@ -116,8 +111,6 @@ void HomeActivity::loadRecentCovers(int coverHeight) {
void HomeActivity::onEnter() {
Activity::onEnter();
renderingMutex = xSemaphoreCreateMutex();
// Check if OPDS browser URL is configured
hasOpdsUrl = strlen(SETTINGS.opdsServerUrl) > 0;
@@ -127,28 +120,12 @@ void HomeActivity::onEnter() {
loadRecentBooks(metrics.homeRecentBooksCount);
// Trigger first update
updateRequired = true;
xTaskCreate(&HomeActivity::taskTrampoline, "HomeActivityTask",
8192, // Stack size
this, // Parameters
1, // Priority
&displayTaskHandle // Task handle
);
requestUpdate();
}
void HomeActivity::onExit() {
Activity::onExit();
// Wait until not rendering to delete task to avoid killing mid-instruction to EPD
xSemaphoreTake(renderingMutex, portMAX_DELAY);
if (displayTaskHandle) {
vTaskDelete(displayTaskHandle);
displayTaskHandle = nullptr;
}
vSemaphoreDelete(renderingMutex);
renderingMutex = nullptr;
// Free the stored cover buffer if any
freeCoverBuffer();
}
@@ -200,12 +177,12 @@ void HomeActivity::loop() {
buttonNavigator.onNext([this, menuCount] {
selectorIndex = ButtonNavigator::nextIndex(selectorIndex, menuCount);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onPrevious([this, menuCount] {
selectorIndex = ButtonNavigator::previousIndex(selectorIndex, menuCount);
updateRequired = true;
requestUpdate();
});
if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
@@ -234,19 +211,7 @@ void HomeActivity::loop() {
}
}
void HomeActivity::displayTaskLoop() {
while (true) {
if (updateRequired) {
updateRequired = false;
xSemaphoreTake(renderingMutex, portMAX_DELAY);
render();
xSemaphoreGive(renderingMutex);
}
vTaskDelay(10 / portTICK_PERIOD_MS);
}
}
void HomeActivity::render() {
void HomeActivity::render(Activity::RenderLock&&) {
auto metrics = UITheme::getInstance().getMetrics();
const auto pageWidth = renderer.getScreenWidth();
const auto pageHeight = renderer.getScreenHeight();
@@ -282,7 +247,7 @@ void HomeActivity::render() {
if (!firstRenderDone) {
firstRenderDone = true;
updateRequired = true;
requestUpdate();
} else if (!recentsLoaded && !recentsLoading) {
recentsLoading = true;
loadRecentCovers(metrics.homeCoverHeight);

11
src/activities/home/HomeActivity.h
View File

@@ -1,8 +1,4 @@
#pragma once
#include <freertos/FreeRTOS.h>
#include <freertos/semphr.h>
#include <freertos/task.h>
#include <functional>
#include <vector>
@@ -14,11 +10,8 @@ struct RecentBook;
struct Rect;
class HomeActivity final : public Activity {
TaskHandle_t displayTaskHandle = nullptr;
SemaphoreHandle_t renderingMutex = nullptr;
ButtonNavigator buttonNavigator;
int selectorIndex = 0;
bool updateRequired = false;
bool recentsLoading = false;
bool recentsLoaded = false;
bool firstRenderDone = false;
@@ -34,9 +27,6 @@ class HomeActivity final : public Activity {
const std::function<void()> onFileTransferOpen;
const std::function<void()> onOpdsBrowserOpen;
static void taskTrampoline(void* param);
[[noreturn]] void displayTaskLoop();
void render();
int getMenuItemCount() const;
bool storeCoverBuffer(); // Store frame buffer for cover image
bool restoreCoverBuffer(); // Restore frame buffer from stored cover
@@ -60,4 +50,5 @@ class HomeActivity final : public Activity {
void onEnter() override;
void onExit() override;
void loop() override;
void render(Activity::RenderLock&&) override;
};

53
src/activities/home/MyLibraryActivity.cpp
View File

@@ -66,11 +66,6 @@ void sortFileList(std::vector<std::string>& strs) {
});
}
void MyLibraryActivity::taskTrampoline(void* param) {
auto* self = static_cast<MyLibraryActivity*>(param);
self->displayTaskLoop();
}
void MyLibraryActivity::loadFiles() {
files.clear();
@@ -109,33 +104,14 @@ void MyLibraryActivity::loadFiles() {
void MyLibraryActivity::onEnter() {
Activity::onEnter();
renderingMutex = xSemaphoreCreateMutex();
loadFiles();
selectorIndex = 0;
updateRequired = true;
xTaskCreate(&MyLibraryActivity::taskTrampoline, "MyLibraryActivityTask",
4096, // Stack size
this, // Parameters
1, // Priority
&displayTaskHandle // Task handle
);
requestUpdate();
}
void MyLibraryActivity::onExit() {
Activity::onExit();
// Wait until not rendering to delete task to avoid killing mid-instruction to EPD
xSemaphoreTake(renderingMutex, portMAX_DELAY);
if (displayTaskHandle) {
vTaskDelete(displayTaskHandle);
displayTaskHandle = nullptr;
}
vSemaphoreDelete(renderingMutex);
renderingMutex = nullptr;
files.clear();
}
@@ -146,7 +122,6 @@ void MyLibraryActivity::loop() {
basepath = "/";
loadFiles();
selectorIndex = 0;
updateRequired = true;
return;
}
@@ -162,7 +137,7 @@ void MyLibraryActivity::loop() {
basepath += files[selectorIndex].substr(0, files[selectorIndex].length() - 1);
loadFiles();
selectorIndex = 0;
updateRequired = true;
requestUpdate();
} else {
onSelectBook(basepath + files[selectorIndex]);
return;
@@ -183,7 +158,7 @@ void MyLibraryActivity::loop() {
const std::string dirName = oldPath.substr(pos + 1) + "/";
selectorIndex = findEntry(dirName);
updateRequired = true;
requestUpdate();
} else {
onGoHome();
}
@@ -194,38 +169,26 @@ void MyLibraryActivity::loop() {
buttonNavigator.onNextRelease([this, listSize] {
selectorIndex = ButtonNavigator::nextIndex(static_cast<int>(selectorIndex), listSize);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onPreviousRelease([this, listSize] {
selectorIndex = ButtonNavigator::previousIndex(static_cast<int>(selectorIndex), listSize);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onNextContinuous([this, listSize, pageItems] {
selectorIndex = ButtonNavigator::nextPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onPreviousContinuous([this, listSize, pageItems] {
selectorIndex = ButtonNavigator::previousPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
updateRequired = true;
requestUpdate();
});
}
void MyLibraryActivity::displayTaskLoop() {
while (true) {
if (updateRequired) {
updateRequired = false;
xSemaphoreTake(renderingMutex, portMAX_DELAY);
render();
xSemaphoreGive(renderingMutex);
}
vTaskDelay(10 / portTICK_PERIOD_MS);
}
}
void MyLibraryActivity::render() const {
void MyLibraryActivity::render(Activity::RenderLock&&) {
renderer.clearScreen();
const auto pageWidth = renderer.getScreenWidth();

12
src/activities/home/MyLibraryActivity.h
View File

@@ -1,8 +1,4 @@
#pragma once
#include <freertos/FreeRTOS.h>
#include <freertos/semphr.h>
#include <freertos/task.h>
#include <functional>
#include <string>
#include <vector>
@@ -13,12 +9,9 @@
class MyLibraryActivity final : public Activity {
private:
TaskHandle_t displayTaskHandle = nullptr;
SemaphoreHandle_t renderingMutex = nullptr;
ButtonNavigator buttonNavigator;
size_t selectorIndex = 0;
bool updateRequired = false;
// Files state
std::string basepath = "/";
@@ -28,10 +21,6 @@ class MyLibraryActivity final : public Activity {
const std::function<void(const std::string& path)> onSelectBook;
const std::function<void()> onGoHome;
static void taskTrampoline(void* param);
[[noreturn]] void displayTaskLoop();
void render() const;
// Data loading
void loadFiles();
size_t findEntry(const std::string& name) const;
@@ -48,4 +37,5 @@ class MyLibraryActivity final : public Activity {
void onEnter() override;
void onExit() override;
void loop() override;
void render(Activity::RenderLock&&) override;
};

48
src/activities/home/RecentBooksActivity.cpp
View File

@@ -15,11 +15,6 @@ namespace {
constexpr unsigned long GO_HOME_MS = 1000;
} // namespace
void RecentBooksActivity::taskTrampoline(void* param) {
auto* self = static_cast<RecentBooksActivity*>(param);
self->displayTaskLoop();
}
void RecentBooksActivity::loadRecentBooks() {
recentBooks.clear();
const auto& books = RECENT_BOOKS.getBooks();
@@ -37,34 +32,15 @@ void RecentBooksActivity::loadRecentBooks() {
void RecentBooksActivity::onEnter() {
Activity::onEnter();
renderingMutex = xSemaphoreCreateMutex();
// Load data
loadRecentBooks();
selectorIndex = 0;
updateRequired = true;
xTaskCreate(&RecentBooksActivity::taskTrampoline, "RecentBooksActivityTask",
4096, // Stack size
this, // Parameters
1, // Priority
&displayTaskHandle // Task handle
);
requestUpdate();
}
void RecentBooksActivity::onExit() {
Activity::onExit();
// Wait until not rendering to delete task to avoid killing mid-instruction to EPD
xSemaphoreTake(renderingMutex, portMAX_DELAY);
if (displayTaskHandle) {
vTaskDelete(displayTaskHandle);
displayTaskHandle = nullptr;
}
vSemaphoreDelete(renderingMutex);
renderingMutex = nullptr;
recentBooks.clear();
}
@@ -87,38 +63,26 @@ void RecentBooksActivity::loop() {
buttonNavigator.onNextRelease([this, listSize] {
selectorIndex = ButtonNavigator::nextIndex(static_cast<int>(selectorIndex), listSize);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onPreviousRelease([this, listSize] {
selectorIndex = ButtonNavigator::previousIndex(static_cast<int>(selectorIndex), listSize);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onNextContinuous([this, listSize, pageItems] {
selectorIndex = ButtonNavigator::nextPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
updateRequired = true;
requestUpdate();
});
buttonNavigator.onPreviousContinuous([this, listSize, pageItems] {
selectorIndex = ButtonNavigator::previousPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
updateRequired = true;
requestUpdate();
});
}
void RecentBooksActivity::displayTaskLoop() {
while (true) {
if (updateRequired) {
updateRequired = false;
xSemaphoreTake(renderingMutex, portMAX_DELAY);
render();
xSemaphoreGive(renderingMutex);
}
vTaskDelay(10 / portTICK_PERIOD_MS);
}
}
void RecentBooksActivity::render() const {
void RecentBooksActivity::render(Activity::RenderLock&&) {
renderer.clearScreen();
const auto pageWidth = renderer.getScreenWidth();

11
src/activities/home/RecentBooksActivity.h
View File

@@ -1,7 +1,4 @@
#pragma once
#include <freertos/FreeRTOS.h>
#include <freertos/semphr.h>
#include <freertos/task.h>
#include <functional>
#include <string>
@@ -13,12 +10,9 @@
class RecentBooksActivity final : public Activity {
private:
TaskHandle_t displayTaskHandle = nullptr;
SemaphoreHandle_t renderingMutex = nullptr;
ButtonNavigator buttonNavigator;
size_t selectorIndex = 0;
bool updateRequired = false;
// Recent tab state
std::vector<RecentBook> recentBooks;
@@ -27,10 +21,6 @@ class RecentBooksActivity final : public Activity {
const std::function<void(const std::string& path)> onSelectBook;
const std::function<void()> onGoHome;
static void taskTrampoline(void* param);
[[noreturn]] void displayTaskLoop();
void render() const;
// Data loading
void loadRecentBooks();
@@ -42,4 +32,5 @@ class RecentBooksActivity final : public Activity {
void onEnter() override;
void onExit() override;
void loop() override;
void render(Activity::RenderLock&&) override;
};