trace2/tr2_tls.h

   1 #ifndef TR2_TLS_H
   2 #define TR2_TLS_H
   3
   4 #include "strbuf.h"
   5 #include "trace2/tr2_ctr.h"
   6 #include "trace2/tr2_tmr.h"
   7
   8 /*
   9  * Notice: the term "TLS" refers to "thread-local storage" in the
  10  * Trace2 source files.  This usage is borrowed from GCC and Windows.
  11  * There is NO relation to "transport layer security".
  12  */
  13
  14 /*
  15  * Arbitry limit for thread names for column alignment.
  16  */
  17 #define TR2_MAX_THREAD_NAME (24)
  18
  19 struct tr2tls_thread_ctx {
  20         const char *thread_name;
  21         uint64_t *array_us_start;
  22         size_t alloc;
  23         size_t nr_open_regions; /* plays role of "nr" in ALLOC_GROW */
  24         int thread_id;
  25         struct tr2_timer_block timer_block;
  26         struct tr2_counter_block counter_block;
  27         unsigned int used_any_timer:1;
  28         unsigned int used_any_per_thread_timer:1;
  29         unsigned int used_any_counter:1;
  30         unsigned int used_any_per_thread_counter:1;
  31 };
  32
  33 /*
  34  * Create thread-local storage for the current thread.
  35  *
  36  * The first thread in the process will have:
  37  *     { .thread_id=0, .thread_name="main" }
  38  * Subsequent threads are given a non-zero thread_id and a thread_name
  39  * constructed from the id and a thread base name (which is usually just
  40  * the name of the thread-proc function).  For example:
  41  *     { .thread_id=10, .thread_name="th10:fsm-listen" }
  42  * This helps to identify and distinguish messages from concurrent threads.
  43  * The ctx.thread_name field is truncated if necessary to help with column
  44  * alignment in printf-style messages.
  45  *
  46  * In this and all following functions the term "self" refers to the
  47  * current thread.
  48  */
  49 struct tr2tls_thread_ctx *tr2tls_create_self(const char *thread_base_name,
  50                                              uint64_t us_thread_start);
  51
  52 /*
  53  * Get the thread-local storage pointer of the current thread.
  54  */
  55 struct tr2tls_thread_ctx *tr2tls_get_self(void);
  56
  57 /*
  58  * return true if the current thread is the main thread.
  59  */
  60 int tr2tls_is_main_thread(void);
  61
  62 /*
  63  * Free the current thread's thread-local storage.
  64  */
  65 void tr2tls_unset_self(void);
  66
  67 /*
  68  * Begin a new nested region and remember the start time.
  69  */
  70 void tr2tls_push_self(uint64_t us_now);
  71
  72 /*
  73  * End the innermost nested region.
  74  */
  75 void tr2tls_pop_self(void);
  76
  77 /*
  78  * Pop any extra (above the first) open regions on the current
  79  * thread and discard.  During a thread-exit, we should only
  80  * have region[0] that was pushed in trace2_thread_start() if
  81  * the thread exits normally.
  82  */
  83 void tr2tls_pop_unwind_self(void);
  84
  85 /*
  86  * Compute the elapsed time since the innermost region in the
  87  * current thread started and the given time (usually now).
  88  */
  89 uint64_t tr2tls_region_elasped_self(uint64_t us);
  90
  91 /*
  92  * Compute the elapsed time since the main thread started
  93  * and the given time (usually now).  This is assumed to
  94  * be the absolute run time of the process.
  95  */
  96 uint64_t tr2tls_absolute_elapsed(uint64_t us);
  97
  98 /*
  99  * Initialize thread-local storage for Trace2.
 100  */
 101 void tr2tls_init(void);
 102
 103 /*
 104  * Free all Trace2 thread-local storage resources.
 105  */
 106 void tr2tls_release(void);
 107
 108 /*
 109  * Protected increment of an integer.
 110  */
 111 int tr2tls_locked_increment(int *p);
 112
 113 /*
 114  * Capture the process start time and do nothing else.
 115  */
 116 void tr2tls_start_process_clock(void);
 117
 118 /*
 119  * Explicitly lock/unlock our mutex.
 120  */
 121 void tr2tls_lock(void);
 122 void tr2tls_unlock(void);
 123
 124 #endif /* TR2_TLS_H */