Merge pull request #508 from hathach/fix-edpt-race

Fix edpt xfer race condition
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Ha Thach 2020-09-14 23:56:21 +07:00 committed by GitHub
commit 745c15d5b5
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6 changed files with 169 additions and 43 deletions

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@ -73,18 +73,29 @@ typedef struct
//--------------------------------------------------------------------+
CFG_TUSB_MEM_SECTION static cdcd_interface_t _cdcd_itf[CFG_TUD_CDC];
static void _prep_out_transaction (uint8_t itf)
static void _prep_out_transaction (cdcd_interface_t* p_cdc)
{
cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
// skip if previous transfer not complete
if ( usbd_edpt_busy(TUD_OPT_RHPORT, p_cdc->ep_out) ) return;
uint8_t const rhport = TUD_OPT_RHPORT;
uint16_t available = tu_fifo_remaining(&p_cdc->rx_ff);
// Prepare for incoming data but only allow what we can store in the ring buffer.
uint16_t max_read = tu_fifo_remaining(&p_cdc->rx_ff);
if ( max_read >= sizeof(p_cdc->epout_buf) )
// TODO Actually we can still carry out the transfer, keeping count of received bytes
// and slowly move it to the FIFO when read().
// This pre-check reduces endpoint claiming
TU_VERIFY(available >= sizeof(p_cdc->epout_buf), );
// claim endpoint
TU_VERIFY(usbd_edpt_claim(rhport, p_cdc->ep_out), );
// fifo can be changed before endpoint is claimed
available = tu_fifo_remaining(&p_cdc->rx_ff);
if ( available >= sizeof(p_cdc->epout_buf) ) {
usbd_edpt_xfer(rhport, p_cdc->ep_out, p_cdc->epout_buf, sizeof(p_cdc->epout_buf));
}else
{
usbd_edpt_xfer(TUD_OPT_RHPORT, p_cdc->ep_out, p_cdc->epout_buf, sizeof(p_cdc->epout_buf));
// Release endpoint since we don't make any transfer
usbd_edpt_release(rhport, p_cdc->ep_out);
}
}
@ -123,8 +134,9 @@ uint32_t tud_cdc_n_available(uint8_t itf)
uint32_t tud_cdc_n_read(uint8_t itf, void* buffer, uint32_t bufsize)
{
uint32_t num_read = tu_fifo_read_n(&_cdcd_itf[itf].rx_ff, buffer, bufsize);
_prep_out_transaction(itf);
cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
uint32_t num_read = tu_fifo_read_n(&p_cdc->rx_ff, buffer, bufsize);
_prep_out_transaction(p_cdc);
return num_read;
}
@ -135,8 +147,9 @@ bool tud_cdc_n_peek(uint8_t itf, int pos, uint8_t* chr)
void tud_cdc_n_read_flush (uint8_t itf)
{
tu_fifo_clear(&_cdcd_itf[itf].rx_ff);
_prep_out_transaction(itf);
cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
tu_fifo_clear(&p_cdc->rx_ff);
_prep_out_transaction(p_cdc);
}
//--------------------------------------------------------------------+
@ -144,11 +157,12 @@ void tud_cdc_n_read_flush (uint8_t itf)
//--------------------------------------------------------------------+
uint32_t tud_cdc_n_write(uint8_t itf, void const* buffer, uint32_t bufsize)
{
uint16_t ret = tu_fifo_write_n(&_cdcd_itf[itf].tx_ff, buffer, bufsize);
cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
uint16_t ret = tu_fifo_write_n(&p_cdc->tx_ff, buffer, bufsize);
#if 0 // TODO issue with circuitpython's REPL
// flush if queue more than endpoint size
if ( tu_fifo_count(&_cdcd_itf[itf].tx_ff) >= CFG_TUD_CDC_EP_BUFSIZE )
if ( tu_fifo_count(&p_cdc->tx_ff) >= CFG_TUD_CDC_EP_BUFSIZE )
{
tud_cdc_n_write_flush(itf);
}
@ -161,17 +175,28 @@ uint32_t tud_cdc_n_write_flush (uint8_t itf)
{
cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
// skip if previous transfer not complete yet
TU_VERIFY( !usbd_edpt_busy(TUD_OPT_RHPORT, p_cdc->ep_in), 0 );
// No data to send
if ( !tu_fifo_count(&p_cdc->tx_ff) ) return 0;
uint16_t count = tu_fifo_read_n(&p_cdc->tx_ff, p_cdc->epin_buf, sizeof(p_cdc->epin_buf));
if ( count )
uint8_t const rhport = TUD_OPT_RHPORT;
// Claim the endpoint
TU_VERIFY( usbd_edpt_claim(rhport, p_cdc->ep_in), 0 );
// Pull data from FIFO
uint16_t const count = tu_fifo_read_n(&p_cdc->tx_ff, p_cdc->epin_buf, sizeof(p_cdc->epin_buf));
if ( count && tud_cdc_n_connected(itf) )
{
TU_VERIFY( tud_cdc_n_connected(itf), 0 ); // fifo is empty if not connected
TU_ASSERT( usbd_edpt_xfer(TUD_OPT_RHPORT, p_cdc->ep_in, p_cdc->epin_buf, count), 0 );
TU_ASSERT( usbd_edpt_xfer(rhport, p_cdc->ep_in, p_cdc->epin_buf, count), 0 );
return count;
}else
{
// Release endpoint since we don't make any transfer
// Note: data is dropped if terminal is not connected
usbd_edpt_release(rhport, p_cdc->ep_in);
return 0;
}
return count;
}
uint32_t tud_cdc_n_write_available (uint8_t itf)
@ -194,7 +219,7 @@ void cdcd_init(void)
p_cdc->wanted_char = -1;
// default line coding is : stop bit = 1, parity = none, data bits = 8
p_cdc->line_coding.bit_rate = 115200;
p_cdc->line_coding.bit_rate = 115200;
p_cdc->line_coding.stop_bits = 0;
p_cdc->line_coding.parity = 0;
p_cdc->line_coding.data_bits = 8;
@ -233,8 +258,7 @@ uint16_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint1
// Find available interface
cdcd_interface_t * p_cdc = NULL;
uint8_t cdc_id;
for(cdc_id=0; cdc_id<CFG_TUD_CDC; cdc_id++)
for(uint8_t cdc_id=0; cdc_id<CFG_TUD_CDC; cdc_id++)
{
if ( _cdcd_itf[cdc_id].ep_in == 0 )
{
@ -283,7 +307,7 @@ uint16_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint1
}
// Prepare for incoming data
_prep_out_transaction(cdc_id);
_prep_out_transaction(p_cdc);
return drv_len;
}
@ -408,7 +432,7 @@ bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_
if (tud_cdc_rx_cb && tu_fifo_count(&p_cdc->rx_ff) ) tud_cdc_rx_cb(itf);
// prepare for OUT transaction
_prep_out_transaction(itf);
_prep_out_transaction(p_cdc);
}
// Data sent to host, we continue to fetch from tx fifo to send.
@ -421,12 +445,15 @@ bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_
if ( 0 == tud_cdc_n_write_flush(itf) )
{
// There is no data left, a ZLP should be sent if
// If there is no data left, a ZLP should be sent if
// xferred_bytes is multiple of EP size and not zero
// FIXME CFG_TUD_CDC_EP_BUFSIZE is not Endpoint packet size
if ( xferred_bytes && (0 == (xferred_bytes % CFG_TUD_CDC_EP_BUFSIZE)) )
if ( !tu_fifo_count(&p_cdc->tx_ff) && xferred_bytes && (0 == (xferred_bytes % CFG_TUD_CDC_EP_BUFSIZE)) )
{
usbd_edpt_xfer(rhport, p_cdc->ep_in, NULL, 0);
if ( usbd_edpt_claim(rhport, p_cdc->ep_in) )
{
usbd_edpt_xfer(rhport, p_cdc->ep_in, NULL, 0);
}
}
}
}

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@ -92,7 +92,7 @@ uint32_t tud_cdc_n_write (uint8_t itf, void const* buffer, uint32_t bu
static inline
uint32_t tud_cdc_n_write_char (uint8_t itf, char ch);
// Write a nul-terminated string
// Write a null-terminated string
static inline
uint32_t tud_cdc_n_write_str (uint8_t itf, char const* str);

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@ -72,18 +72,21 @@ static inline hidd_interface_t* get_interface_by_itfnum(uint8_t itf_num)
//--------------------------------------------------------------------+
bool tud_hid_ready(void)
{
uint8_t itf = 0;
uint8_t const itf = 0;
uint8_t const ep_in = _hidd_itf[itf].ep_in;
return tud_ready() && (ep_in != 0) && usbd_edpt_ready(TUD_OPT_RHPORT, ep_in);
return tud_ready() && (ep_in != 0) && !usbd_edpt_busy(TUD_OPT_RHPORT, ep_in);
}
bool tud_hid_report(uint8_t report_id, void const* report, uint8_t len)
{
TU_VERIFY( tud_hid_ready() );
uint8_t itf = 0;
uint8_t const rhport = 0;
uint8_t const itf = 0;
hidd_interface_t * p_hid = &_hidd_itf[itf];
// claim endpoint
TU_VERIFY( usbd_edpt_claim(rhport, p_hid->ep_in) );
// prepare data
if (report_id)
{
len = tu_min8(len, CFG_TUD_HID_EP_BUFSIZE-1);

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@ -153,15 +153,25 @@ void midi_rx_done_cb(midid_interface_t* midi, uint8_t const* buffer, uint32_t bu
static uint32_t write_flush(midid_interface_t* midi)
{
// No data to send
if ( !tu_fifo_count(&midi->tx_ff) ) return 0;
uint8_t const rhport = TUD_OPT_RHPORT;
// skip if previous transfer not complete
TU_VERIFY( !usbd_edpt_busy(TUD_OPT_RHPORT, midi->ep_in) );
TU_VERIFY( usbd_edpt_claim(rhport, midi->ep_in), 0 );
uint16_t count = tu_fifo_read_n(&midi->tx_ff, midi->epin_buf, CFG_TUD_MIDI_EP_BUFSIZE);
if (count > 0)
{
TU_ASSERT( usbd_edpt_xfer(TUD_OPT_RHPORT, midi->ep_in, midi->epin_buf, count) );
TU_ASSERT( usbd_edpt_xfer(rhport, midi->ep_in, midi->epin_buf, count), 0 );
return count;
}else
{
// Release endpoint since we don't make any transfer
usbd_edpt_release(rhport, midi->ep_in);
return 0;
}
return count;
}
uint32_t tud_midi_n_write(uint8_t itf, uint8_t jack_id, uint8_t const* buffer, uint32_t bufsize)
@ -405,17 +415,22 @@ bool midid_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32
if (tud_midi_rx_cb) tud_midi_rx_cb(itf);
// prepare for next
// TODO for now ep_out is not used by public API therefore there is no race condition,
// and does not need to claim like ep_in
TU_ASSERT(usbd_edpt_xfer(rhport, p_midi->ep_out, p_midi->epout_buf, CFG_TUD_MIDI_EP_BUFSIZE), false);
}
else if ( ep_addr == p_midi->ep_in )
{
if (0 == write_flush(p_midi))
{
// There is no data left, a ZLP should be sent if
// If there is no data left, a ZLP should be sent if
// xferred_bytes is multiple of EP size and not zero
if ( xferred_bytes && (0 == (xferred_bytes % CFG_TUD_MIDI_EP_BUFSIZE)) )
if ( !tu_fifo_count(&p_midi->tx_ff) && xferred_bytes && (0 == (xferred_bytes % CFG_TUD_MIDI_EP_BUFSIZE)) )
{
usbd_edpt_xfer(rhport, p_midi->ep_in, NULL, 0);
if ( usbd_edpt_claim(rhport, p_midi->ep_in) )
{
usbd_edpt_xfer(rhport, p_midi->ep_in, NULL, 0);
}
}
}
}

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@ -63,9 +63,11 @@ typedef struct
{
volatile bool busy : 1;
volatile bool stalled : 1;
volatile bool claimed : 1;
// TODO merge ep2drv here, 4-bit should be sufficient
}ep_status[8][2];
}usbd_device_t;
static usbd_device_t _usbd_dev;
@ -237,6 +239,13 @@ static inline usbd_class_driver_t const * get_driver(uint8_t drvid)
OSAL_QUEUE_DEF(OPT_MODE_DEVICE, _usbd_qdef, CFG_TUD_TASK_QUEUE_SZ, dcd_event_t);
static osal_queue_t _usbd_q;
// Mutex for claiming endpoint, only needed when using with preempted RTOS
#if CFG_TUSB_OS != OPT_OS_NONE
static osal_mutex_def_t _ubsd_mutexdef;
static osal_mutex_t _usbd_mutex;
#endif
//--------------------------------------------------------------------+
// Prototypes
//--------------------------------------------------------------------+
@ -351,9 +360,15 @@ bool tud_init (void)
tu_varclr(&_usbd_dev);
#if CFG_TUSB_OS != OPT_OS_NONE
// Init device mutex
_usbd_mutex = osal_mutex_create(&_ubsd_mutexdef);
TU_ASSERT(_usbd_mutex);
#endif
// Init device queue & task
_usbd_q = osal_queue_create(&_usbd_qdef);
TU_ASSERT(_usbd_q != NULL);
TU_ASSERT(_usbd_q);
// Get application driver if available
if ( usbd_app_driver_get_cb )
@ -478,6 +493,7 @@ void tud_task (void)
TU_LOG2("on EP %02X with %u bytes\r\n", ep_addr, (unsigned int) event.xfer_complete.len);
_usbd_dev.ep_status[epnum][ep_dir].busy = false;
_usbd_dev.ep_status[epnum][ep_dir].claimed = 0;
if ( 0 == epnum )
{
@ -1076,6 +1092,59 @@ bool usbd_edpt_open(uint8_t rhport, tusb_desc_endpoint_t const * desc_ep)
return dcd_edpt_open(rhport, desc_ep);
}
bool usbd_edpt_claim(uint8_t rhport, uint8_t ep_addr)
{
(void) rhport;
uint8_t const epnum = tu_edpt_number(ep_addr);
uint8_t const dir = tu_edpt_dir(ep_addr);
#if CFG_TUSB_OS != OPT_OS_NONE
// pre-check to help reducing mutex lock
TU_VERIFY((_usbd_dev.ep_status[epnum][dir].busy == 0) && (_usbd_dev.ep_status[epnum][dir].claimed == 0));
osal_mutex_lock(_usbd_mutex, OSAL_TIMEOUT_WAIT_FOREVER);
#endif
// can only claim the endpoint if it is not busy and not claimed yet.
bool const ret = (_usbd_dev.ep_status[epnum][dir].busy == 0) && (_usbd_dev.ep_status[epnum][dir].claimed == 0);
if (ret)
{
_usbd_dev.ep_status[epnum][dir].claimed = 1;
}
#if CFG_TUSB_OS != OPT_OS_NONE
osal_mutex_unlock(_usbd_mutex);
#endif
return ret;
}
bool usbd_edpt_release(uint8_t rhport, uint8_t ep_addr)
{
(void) rhport;
uint8_t const epnum = tu_edpt_number(ep_addr);
uint8_t const dir = tu_edpt_dir(ep_addr);
#if CFG_TUSB_OS != OPT_OS_NONE
osal_mutex_lock(_usbd_mutex, OSAL_TIMEOUT_WAIT_FOREVER);
#endif
// can only release the endpoint if it is claimed and not busy
bool const ret = (_usbd_dev.ep_status[epnum][dir].busy == 0) && (_usbd_dev.ep_status[epnum][dir].claimed == 1);
if (ret)
{
_usbd_dev.ep_status[epnum][dir].claimed = 0;
}
#if CFG_TUSB_OS != OPT_OS_NONE
osal_mutex_unlock(_usbd_mutex);
#endif
return ret;
}
bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
{
uint8_t const epnum = tu_edpt_number(ep_addr);
@ -1083,6 +1152,9 @@ bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
TU_LOG2(" Queue EP %02X with %u bytes ... ", ep_addr, total_bytes);
// Attempt to transfer on a busy endpoint, sound like an race condition !
TU_ASSERT(_usbd_dev.ep_status[epnum][dir].busy == 0);
// Set busy first since the actual transfer can be complete before dcd_edpt_xfer() could return
// and usbd task can preempt and clear the busy
_usbd_dev.ep_status[epnum][dir].busy = true;
@ -1093,7 +1165,9 @@ bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
return true;
}else
{
// DCD error, mark endpoint as ready to allow next transfer
_usbd_dev.ep_status[epnum][dir].busy = false;
_usbd_dev.ep_status[epnum][dir].claimed = 0;
TU_LOG2("failed\r\n");
TU_BREAKPOINT();
return false;

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@ -70,6 +70,13 @@ void usbd_edpt_close(uint8_t rhport, uint8_t ep_addr);
// Submit a usb transfer
bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes);
// Claim an endpoint before submitting a transfer.
// If caller does not make any transfer, it must release endpoint for others.
bool usbd_edpt_claim(uint8_t rhport, uint8_t ep_addr);
// Release an endpoint without submitting a transfer
bool usbd_edpt_release(uint8_t rhport, uint8_t ep_addr);
// Check if endpoint transferring is complete
bool usbd_edpt_busy(uint8_t rhport, uint8_t ep_addr);