2 * Written by Josh Dybnis and released to the public domain, as explained at
3 * http://creativecommons.org/licenses/publicdomain
14 #define LWT_BUFFER_SCALE 16
15 #define LWT_BUFFER_SIZE (1 << LWT_BUFFER_SCALE)
16 #define LWT_BUFFER_MASK (LWT_BUFFER_SIZE - 1)
18 typedef struct lwt_record {
25 typedef struct lwt_buffer {
30 DECLARE_THREAD_LOCAL(tb_, int);
32 lwt_buffer_t *lwt_buf_[MAX_NUM_THREADS] = {};
33 uint64_t flag_mask_ = 0;
34 static int buf_count_ = 0;
35 static const char *flags_ = "";
39 INIT_THREAD_LOCAL(tb_, NULL);
42 void lwt_thread_init (int thread_id)
44 assert(thread_id < MAX_NUM_THREADS);
45 if (lwt_buf_[thread_id] == NULL) {
46 lwt_buf_[thread_id] = (lwt_buffer_t *)nbd_malloc(sizeof(lwt_buffer_t) + sizeof(lwt_record_t) * LWT_BUFFER_SIZE);
47 SYNC_ADD(&buf_count_, 1);
48 memset(lwt_buf_[thread_id], 0, sizeof(lwt_buffer_t));
49 SET_THREAD_LOCAL(tb_, lwt_buf_[thread_id]);
53 void lwt_set_trace_level (const char *flags)
55 assert(strlen(flags) % 2 == 0); // a well formed <flags> should be an even number of characters long
58 for (i = 0; flags[i]; i+=2) {
59 flag_mask_ |= 1 << (flags[i] - 'A');
63 static inline void dump_record (FILE *file, int thread_id, lwt_record_t *r, uint64_t offset)
65 // print the record if its trace category is enabled at a high enough level
66 int flag = (size_t)r->format >> 56;
67 int level = ((size_t)r->format >> 48) & 0xFF;
68 const char *f = strchr(flags_, flag);
69 if (f != NULL && level <= f[1]) {
70 char s[3] = {flag, level, '\0'};
71 fprintf(file, "%09llu %d %s ", ((uint64_t)r->timestamp - offset) >> 6, thread_id, s);
72 const char *format = (const char *)(((uint64_t)r->format << 16) >> 16); // strip out the embedded flags
73 fprintf(file, format, r->value1, r->value2);
78 static void dump_buffer (FILE *file, int thread_id, uint64_t offset)
80 assert(thread_id < buf_count_);
82 lwt_buffer_t *tb = lwt_buf_[thread_id];
84 if (tb->head > LWT_BUFFER_SIZE) {
85 for (i = tb->head & LWT_BUFFER_MASK; i < LWT_BUFFER_SIZE; ++i) {
86 dump_record(file, thread_id, tb->x + i, offset);
90 for (i = 0; i < (tb->head & LWT_BUFFER_MASK); ++i) {
91 dump_record(file, thread_id, tb->x + i, offset);
95 void lwt_dump (const char *file_name)
97 uint64_t offset = (uint64_t)-1;
100 for (i = 0; i < buf_count_; ++i) {
101 if (lwt_buf_[i] != NULL && lwt_buf_[i]->head != 0) {
102 uint64_t x = lwt_buf_[i]->x[0].timestamp;
106 if (lwt_buf_[i]->head > LWT_BUFFER_SIZE)
108 x = lwt_buf_[i]->x[lwt_buf_[i]->head & LWT_BUFFER_MASK].timestamp;
116 if (offset != (uint64_t)-1) {
117 FILE *file = fopen(file_name, "w");
119 for (i = 0; i < buf_count_; ++i) {
120 if (lwt_buf_[i] != NULL) {
121 dump_buffer(file, i, offset);
129 void lwt_trace_i (const char *format, size_t value1, size_t value2) {
130 LOCALIZE_THREAD_LOCAL(tb_, lwt_buffer_t *);
133 __asm__ __volatile__("rdtsc" : "=a" (l), "=d" (u));
134 uint64_t timestamp = ((uint64_t)u << 32) | l;
135 lwt_record_t temp = { timestamp, format, value1, value2 };
136 tb_->x[tb_->head++ & LWT_BUFFER_MASK] = temp;