Use a linked list of background tasks to perform

main.c

@@ -45,6 +45,7 @@
 
 #include "background.h"
 #include "mpconfigboard.h"
+#include "supervisor/background_callback.h"
 #include "supervisor/cpu.h"
 #include "supervisor/memory.h"
 #include "supervisor/port.h"
@@ -100,8 +101,6 @@ void start_mp(supervisor_allocation* heap) {
     reset_status_led();
     autoreload_stop();
 
-    background_tasks_reset();
-
     // Stack limit should be less than real stack size, so we have a chance
     // to recover from limit hit.  (Limit is measured in bytes.)
     mp_stack_ctrl_init();
@@ -161,6 +160,8 @@ void stop_mp(void) {
     MP_STATE_VM(vfs_cur) = vfs;
     #endif
 
+    background_callback_reset();
+
     gc_deinit();
 }
 
@@ -492,6 +493,8 @@ void gc_collect(void) {
     // have lost their references in the VM even though they are mounted.
     gc_collect_root((void**)&MP_STATE_VM(vfs_mount_table), sizeof(mp_vfs_mount_t) / sizeof(mp_uint_t));
 
+    background_callback_gc_collect();
+
     #if CIRCUITPY_DISPLAYIO
     displayio_gc_collect();
     #endif

ports/atmel-samd/audio_dma.c

@@ -31,7 +31,7 @@
 
 #include "shared-bindings/audiocore/RawSample.h"
 #include "shared-bindings/audiocore/WaveFile.h"
-#include "supervisor/shared/tick.h"
+#include "supervisor/background_callback.h"
 
 #include "py/mpstate.h"
 #include "py/runtime.h"
@@ -61,7 +61,6 @@ void audio_dma_free_channel(uint8_t channel) {
     assert(audio_dma_allocated[channel]);
     audio_dma_disable_channel(channel);
     audio_dma_allocated[channel] = false;
-    supervisor_disable_tick();
 }
 
 void audio_dma_disable_channel(uint8_t channel) {
@@ -73,7 +72,6 @@ void audio_dma_disable_channel(uint8_t channel) {
 void audio_dma_enable_channel(uint8_t channel) {
     if (channel >= AUDIO_DMA_CHANNEL_COUNT)
         return;
-    supervisor_enable_tick();
     dma_enable_channel(channel);
 }
 
@@ -259,6 +257,15 @@ audio_dma_result audio_dma_setup_playback(audio_dma_t* dma,
         dma->beat_size *= 2;
     }
 
+#ifdef SAM_D5X_E5X
+    int irq = dma->event_channel < 4 ? EVSYS_0_IRQn + dma->event_channel : EVSYS_4_IRQn;
+#else
+    int irq = EVSYS_IRQn;
+#endif
+
+    NVIC_DisableIRQ(irq);
+    NVIC_ClearPendingIRQ(irq);
+
     DmacDescriptor* first_descriptor = dma_descriptor(dma_channel);
     setup_audio_descriptor(first_descriptor, dma->beat_size, output_spacing, output_register_address);
     if (single_buffer) {
@@ -281,6 +288,8 @@ audio_dma_result audio_dma_setup_playback(audio_dma_t* dma,
     dma_configure(dma_channel, dma_trigger_source, true);
     audio_dma_enable_channel(dma_channel);
 
+    NVIC_EnableIRQ(irq);
+
     return AUDIO_DMA_OK;
 }
 
@@ -321,9 +330,6 @@ void audio_dma_reset(void) {
     for (uint8_t i = 0; i < AUDIO_DMA_CHANNEL_COUNT; i++) {
         audio_dma_state[i] = NULL;
         audio_dma_pending[i] = false;
-        if (audio_dma_allocated[i]) {
-            supervisor_disable_tick();
-        }
         audio_dma_allocated[i] = false;
         audio_dma_disable_channel(i);
         dma_descriptor(i)->BTCTRL.bit.VALID = false;
@@ -343,29 +349,39 @@ bool audio_dma_get_playing(audio_dma_t* dma) {
     return (status & DMAC_CHINTFLAG_TERR) == 0;
 }
 
-// WARN(tannewt): DO NOT print from here. Printing calls background tasks such as this and causes a
-// stack overflow.
+// WARN(tannewt): DO NOT print from here, or anything it calls. Printing calls
+// background tasks such as this and causes a stack overflow.
+STATIC void dma_callback_fun(void *arg) {
+    audio_dma_t* dma = arg;
+    if (dma == NULL) {
+        return;
+    }
+
+    audio_dma_load_next_block(dma);
+}
 
-void audio_dma_background(void) {
+void evsyshandler_common(void) {
     for (uint8_t i = 0; i < AUDIO_DMA_CHANNEL_COUNT; i++) {
-        if (audio_dma_pending[i]) {
-            continue;
-        }
         audio_dma_t* dma = audio_dma_state[i];
         if (dma == NULL) {
             continue;
         }
-
         bool block_done = event_interrupt_active(dma->event_channel);
         if (!block_done) {
             continue;
         }
-
-        // audio_dma_load_next_block() can call Python code, which can call audio_dma_background()
-        // recursively at the next background processing time. So disallow recursive calls to here.
-        audio_dma_pending[i] = true;
-        audio_dma_load_next_block(dma);
-        audio_dma_pending[i] = false;
+        background_callback_add(&dma->callback, dma_callback_fun, (void*)dma);
     }
 }
+
+#ifdef SAM_D5X_E5X
+void EVSYS_0_Handler(void) { evsyshandler_common(); }
+void EVSYS_1_Handler(void) { evsyshandler_common(); }
+void EVSYS_2_Handler(void) { evsyshandler_common(); }
+void EVSYS_3_Handler(void) { evsyshandler_common(); }
+void EVSYS_4_Handler(void) { evsyshandler_common(); }
+#else
+void EVSYS_Handler(void) { evsyshandler_common(); }
+#endif
+
 #endif

ports/atmel-samd/audio_dma.h

@@ -31,6 +31,7 @@
 #include "py/obj.h"
 #include "shared-module/audiocore/RawSample.h"
 #include "shared-module/audiocore/WaveFile.h"
+#include "supervisor/background_callback.h"
 
 typedef struct {
     mp_obj_t sample;
@@ -49,6 +50,7 @@ typedef struct {
     uint8_t* second_buffer;
     bool first_descriptor_free;
     DmacDescriptor* second_descriptor;
+    background_callback_t callback;
 } audio_dma_t;
 
 typedef enum {

ports/atmel-samd/background.c

@@ -39,63 +39,21 @@
 #include "shared-module/displayio/__init__.h"
 #endif
 
-volatile uint64_t last_finished_tick = 0;
-
-bool stack_ok_so_far = true;
-
-static bool running_background_tasks = false;
-
 #ifdef MONITOR_BACKGROUND_TASKS
 // PB03 is physical pin "SCL" on the Metro M4 express
 // so you can't use this code AND an i2c peripheral
 // at the same time unless you change this
-STATIC void start_background_task(void) {
+void port_start_background_task(void) {
     REG_PORT_DIRSET1 = (1<<3);
     REG_PORT_OUTSET1 = (1<<3);
 }
 
-STATIC void finish_background_task(void) {
+void port_finish_background_task(void) {
     REG_PORT_OUTCLR1 = (1<<3);
 }
 #else
-STATIC void start_background_task(void) {}
-STATIC void finish_background_task(void) {}
+void port_start_background_task(void) {}
+void port_finish_background_task(void) {}
 #endif
 
-void background_tasks_reset(void) {
-    running_background_tasks = false;
-}
-
-void run_background_tasks(void) {
-    // Don't call ourselves recursively.
-    if (running_background_tasks) {
-        return;
-    }
-
-    start_background_task();
-
-    assert_heap_ok();
-    running_background_tasks = true;
-
-    #if CIRCUITPY_AUDIOIO || CIRCUITPY_AUDIOBUSIO
-    audio_dma_background();
-    #endif
-    #if CIRCUITPY_DISPLAYIO
-    displayio_background();
-    #endif
-
-    #if CIRCUITPY_NETWORK
-    network_module_background();
-    #endif
-    filesystem_background();
-    usb_background();
-    running_background_tasks = false;
-    assert_heap_ok();
-
-    last_finished_tick = port_get_raw_ticks(NULL);
-    finish_background_task();
-}
-
-bool background_tasks_ok(void) {
-    return port_get_raw_ticks(NULL) - last_finished_tick < 1024;
-}
+void port_background_task(void) {}

ports/atmel-samd/background.h

@@ -29,9 +29,4 @@
 
 #include <stdbool.h>
 
-void background_tasks_reset(void);
-void run_background_tasks(void);
-void run_background_vm_tasks(void);
-bool background_tasks_ok(void);
-
 #endif  // MICROPY_INCLUDED_ATMEL_SAMD_BACKGROUND_H

ports/atmel-samd/boards/uchip/mpconfigboard.mk

@@ -9,3 +9,10 @@ CHIP_FAMILY = samd21
 INTERNAL_FLASH_FILESYSTEM = 1
 LONGINT_IMPL = NONE
 CIRCUITPY_FULL_BUILD = 0
+
+# Tweak inlining depending on language.
+ifeq ($(TRANSLATION), zh_Latn_pinyin)
+CFLAGS_INLINE_LIMIT = 45
+else
+CFLAGS_INLINE_LIMIT = 70
+endif

ports/atmel-samd/common-hal/frequencyio/FrequencyIn.c

@@ -46,6 +46,7 @@
 #include "hpl_gclk_config.h"
 
 #include "shared-bindings/time/__init__.h"
+#include "supervisor/shared/tick.h"
 #include "supervisor/shared/translate.h"
 
 #ifdef SAMD21
@@ -132,7 +133,7 @@ void frequencyin_interrupt_handler(uint8_t index) {
             }
 
             // Check if we've reached the upper limit of detection
-            if (!background_tasks_ok() || self->errored_too_fast) {
+            if (!supervisor_background_tasks_ok() || self->errored_too_fast) {
                 self->errored_too_fast = true;
                 frequencyin_emergency_cancel_capture(i);
             }

ports/atmel-samd/common-hal/pulseio/PulseIn.c

@@ -42,6 +42,7 @@
 #include "samd/timers.h"
 #include "shared-bindings/microcontroller/__init__.h"
 #include "shared-bindings/pulseio/PulseIn.h"
+#include "supervisor/shared/tick.h"
 #include "supervisor/shared/translate.h"
 
 // This timer is shared amongst all PulseIn objects as a higher resolution clock.
@@ -87,7 +88,7 @@ void pulsein_interrupt_handler(uint8_t channel) {
     uint32_t current_count = tc->COUNT16.COUNT.reg;
 
     pulseio_pulsein_obj_t* self = get_eic_channel_data(channel);
-    if (!background_tasks_ok() || self->errored_too_fast) {
+    if (!supervisor_background_tasks_ok() || self->errored_too_fast) {
         self->errored_too_fast = true;
         common_hal_pulseio_pulsein_pause(self);
         return;

ports/atmel-samd/supervisor/usb.c

@@ -29,6 +29,8 @@
 #include "hpl/gclk/hpl_gclk_base.h"
 #include "hal_gpio.h"
 #include "lib/tinyusb/src/device/usbd.h"
+#include "supervisor/background_callback.h"
+#include "supervisor/usb.h"
 
 void init_usb_hardware(void) {
     #ifdef SAMD21
@@ -61,24 +63,24 @@ void init_usb_hardware(void) {
 
 #ifdef SAMD21
 void USB_Handler(void) {
-    tud_int_handler(0);
+    usb_irq_handler();
 }
 #endif
 
 #ifdef SAM_D5X_E5X
 void USB_0_Handler (void) {
-  tud_int_handler(0);
+    usb_irq_handler();
 }
 
 void USB_1_Handler (void) {
-  tud_int_handler(0);
+    usb_irq_handler();
 }
 
 void USB_2_Handler (void) {
-  tud_int_handler(0);
+    usb_irq_handler();
 }
 
 void USB_3_Handler (void) {
-  tud_int_handler(0);
+    usb_irq_handler();
 }
 #endif

ports/cxd56/background.c

@@ -30,24 +30,6 @@
 #include "supervisor/filesystem.h"
 #include "supervisor/shared/stack.h"
 
-static bool running_background_tasks = false;
-
-void background_tasks_reset(void) {
-    running_background_tasks = false;
-}
-
-void run_background_tasks(void) {
-    // Don't call ourselves recursively.
-    if (running_background_tasks) {
-        return;
-    }
-
-    assert_heap_ok();
-    running_background_tasks = true;
-
-    usb_background();
-    filesystem_background();
-
-    running_background_tasks = false;
-    assert_heap_ok();
-}
+void port_background_task(void) {}
+void port_start_background_task(void) {}
+void port_finish_background_task(void) {}

ports/cxd56/background.h

@@ -27,7 +27,4 @@
 #ifndef MICROPY_INCLUDED_CXD56_BACKGROUND_H
 #define MICROPY_INCLUDED_CXD56_BACKGROUND_H
 
-void background_tasks_reset(void);
-void run_background_tasks(void);
-
 #endif  // MICROPY_INCLUDED_CXD56_BACKGROUND_H

ports/esp32s2/background.c

@@ -35,27 +35,12 @@
 #include "shared-module/displayio/__init__.h"
 #endif
 
-static bool running_background_tasks = false;
-
-void background_tasks_reset(void) {
-    running_background_tasks = false;
-}
-
-void run_background_tasks(void) {
-    // Don't call ourselves recursively.
-    if (running_background_tasks) {
-        return;
-    }
 
+void port_background_task(void) {
     // Zero delay in case FreeRTOS wants to switch to something else.
     vTaskDelay(0);
-    running_background_tasks = true;
-    filesystem_background();
+}
 
-    #if CIRCUITPY_DISPLAYIO
-    displayio_background();
-    #endif
-    running_background_tasks = false;
+void port_start_background_task(void) {}
 
-    assert_heap_ok();
-}
+void port_finish_background_task(void) {}