beremiz

SVGHMI: Intermediate state while working on svghmi.c
svghmi
2019-09-03, Edouard Tisserant
31785529a657
Parents 302347f48193
Children b20c94352074
SVGHMI: Intermediate state while working on svghmi.c
2 files changed, 100 insertions(+), 13 deletions(-)
  • +97 -11
    svghmi/svghmi.c
  • +3 -2
    svghmi/svghmi.py
    • --- a/svghmi/svghmi.c Mon Aug 26 08:54:02 2019 +0200
    +++ b/svghmi/svghmi.c Tue Sep 03 12:17:33 2019 +0200
    @@ -4,6 +4,7 @@
    #include "config.h"
    #include "beremiz.h"
    +#define DEFAULT_REFRESH_PERIOD_MS 100
    #define HMI_BUFFER_SIZE %(buffer_size)d
    /* PLC reads from that buffer */
    @@ -12,16 +13,38 @@
    /* PLC writes to that buffer */
    static char wbuf[HMI_BUFFER_SIZE];
    -static pthread_mutex_t wbuf_mutex = PTHREAD_MUTEX_INITIALIZER;
    -static pthread_mutex_t rbuf_mutex = PTHREAD_MUTEX_INITIALIZER;
    +%(extern_variables_declarations)s
    +
    +#define ticktime_ns %(PLC_ticktime)d;
    +uint16_t ticktime_ms (ticktime_ns>1000000)?
    + ticktime_ns/1000000:
    + 1;
    -%(extern_variables_declarations)s
    +typedef enum {
    + buf_free = 0,
    + buf_set,
    + buf_tosend
    +} buf_state_t;
    +
    +int global_write_dirty = 0;
    typedef const struct {
    void *ptr;
    __IEC_types_enum type;
    uint32_t buf_index;
    - uint32_t flags;
    +
    + /* publish/write/send */
    + int wlock;
    + /* zero means not subscribed */
    + uint16_t refresh_period_ms;
    + uint16_t age_ms;
    +
    + buf_state_t wstate;
    +
    + /* retrieve/read/recv */
    + int rlock;
    + buf_state_t rstate;
    +
    } hmi_tree_item_t;
    static hmi_tree_item_t hmi_tree_item[] = {
    @@ -51,7 +74,56 @@
    void *visible_value_p = UnpackVar(dsc, &real_value_p, &flags);
    - memcpy(dest_p, visible_value_p, __get_type_enum_size(dsc->type));
    + /* Try take lock */
    + long was_locked = AtomicCompareExchange(&dsc->wlock, 0, 1);
    +
    + if(was_locked) {
    + /* was locked. give up*/
    + return;
    + }
    +
    + if(dsc->wstate == buf_set)
    + /* if being subscribed */
    + if(dsc->refresh_period_ms){
    + if(dsc->age_ms + ticktime_ms < dsc->refresh_period_ms){
    + dsc->age_ms += ticktime_ms;
    + }else{
    + dsc->wstate = buf_tosend;
    + }
    + }
    + }
    +
    + /* if new value differs from previous one */
    + if(memcmp(dest_p, visible_value_p, __get_type_enum_size(dsc->type)) != 0){
    + /* copy and flag as set */
    + memcpy(dest_p, visible_value_p, __get_type_enum_size(dsc->type));
    + if(dsc->wstate == buf_free) {
    + dsc->wstate = buf_set;
    + dsc->age_ms = 0;
    + }
    + global_write_dirty = 1;
    + }
    +
    + /* unlock - use AtomicComparExchange to have memory barrier */
    + AtomicCompareExchange(&dsc->wlock, 1, 0);
    +}
    +
    +struct timespec sending_now;
    +struct timespec next_sending;
    +void send_iterator(hmi_tree_item_t *dsc)
    +{
    + while(AtomicCompareExchange(&dsc->wlock, 0, 1)) sched_yield();
    +
    + // check for variable being modified
    + if(dsc->wstat == buf_tosend){
    + // send
    +
    + // TODO write to some socket
    +
    + dsc->wstate = buf_free;
    + }
    +
    + AtomicCompareExchange(&dsc->wlock, 1, 0);
    }
    void read_iterator(hmi_tree_item_t *dsc)
    @@ -62,6 +134,7 @@
    void *visible_value_p = UnpackVar(dsc, &real_value_p, &flags);
    +
    memcpy(visible_value_p, src_p, __get_type_enum_size(dsc->type));
    }
    @@ -69,6 +142,11 @@
    {
    bzero(rbuf,sizeof(rbuf));
    bzero(wbuf,sizeof(wbuf));
    +
    + // create - connection endpoint
    + // - sending thread
    + // - sending semaphore
    + // - recv thread
    return 0;
    }
    @@ -79,16 +157,24 @@
    void __retrieve_svghmi()
    {
    - if(!pthread_mutex_lock(&rbuf_mutex)){
    - traverse_hmi_tree(read_iterator);
    - pthread_mutex_unlock(&rbuf_mutex);
    - }
    + traverse_hmi_tree(read_iterator);
    }
    void __publish_svghmi()
    {
    - if(!pthread_mutex_lock(&wbuf_mutex)){
    - pthread_mutex_unlock(&wbuf_mutex);
    + global_write_dirty = 0;
    + traverse_hmi_tree(write_iterator);
    + if(global_write_dirty) {
    + // TODO : set emaphore to wakeup sending thread
    }
    +
    }
    +void sending_thread_proc(void* args){
    +
    + // TODO : wait for
    + // - semaphore
    + // - next autonomous send thread wakeup. (impl as wait timeout ?)
    +
    + traverse_hmi_tree(send_iterator);
    +}
    --- a/svghmi/svghmi.py Mon Aug 26 08:54:02 2019 +0200
    +++ b/svghmi/svghmi.py Tue Sep 03 12:17:33 2019 +0200
    @@ -181,7 +181,7 @@
    "OUT": "_O_ENUM",
    "VAR": "_ENUM"
    }[node.vartype] + ", " +
    - str(buf_index) + ", 0}"]
    + str(buf_index) + ", 0, }"]
    buf_index += sz
    if len(node.path) == 1:
    extern_variables_declarations += [
    @@ -208,7 +208,8 @@
    "variable_decl_array": ",\n".join(variable_decl_array),
    "extern_variables_declarations": "\n".join(extern_variables_declarations),
    "buffer_size": buf_index,
    - "var_access_code": targets.GetCode("var_access.c")
    + "var_access_code": targets.GetCode("var_access.c"),
    + "PLC_ticktime": self.GetCTRoot().GetTicktime()
    }
    gen_svghmi_c_path = os.path.join(buildpath, "svghmi.c")