X-Git-Url: http://git.efficios.com/?p=babeltrace.git;a=blobdiff_plain;f=lib%2Ftrace-collection.c;h=4f1379c5a43d73cb4e0bcae9053339bf533f7802;hp=9bc5b1fcc8b0ecc543dd65b7a67734f4c44c8968;hb=c462e188f3e7819c7bc74f671038cdbf36e8c3c0;hpb=7f89ddce05f0a5c985d6333fbe70a992da4bd244 diff --git a/lib/trace-collection.c b/lib/trace-collection.c index 9bc5b1fc..4f1379c5 100644 --- a/lib/trace-collection.c +++ b/lib/trace-collection.c @@ -16,6 +16,14 @@ * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. */ #include #include @@ -24,6 +32,7 @@ #include #include #include /* for clocks */ +#include #include @@ -38,24 +47,24 @@ static void check_clock_match(gpointer key, gpointer value, gpointer user_data) struct clock_match *match = user_data; struct ctf_clock *clock_a = value, *clock_b; - if (clock_a->uuid != 0) { + if (clock_a->absolute) { /* - * Lookup the the trace clocks into the collection - * clocks. + * Absolute time references, such as NTP, are looked up + * by clock name. */ clock_b = g_hash_table_lookup(match->clocks, - (gpointer) (unsigned long) clock_a->uuid); + (gpointer) (unsigned long) clock_a->name); if (clock_b) { match->clock_match = clock_b; return; } - } else if (clock_a->absolute) { + } else if (clock_a->uuid != 0) { /* - * Absolute time references, such as NTP, are looked up - * by clock name. + * Lookup the the trace clocks into the collection + * clocks. */ clock_b = g_hash_table_lookup(match->clocks, - (gpointer) (unsigned long) clock_a->name); + (gpointer) (unsigned long) clock_a->uuid); if (clock_b) { match->clock_match = clock_b; return; @@ -63,6 +72,19 @@ static void check_clock_match(gpointer key, gpointer value, gpointer user_data) } } +/* + * Note: if using a frequency different from 1GHz for clock->offset, it + * is recommended to express the seconds in offset_s, otherwise there + * will be a loss of precision caused by the limited size of the double + * mantissa. + */ +static +uint64_t clock_offset_ns(struct ctf_clock *clock) +{ + return clock->offset_s * 1000000000ULL + + clock_cycles_to_ns(clock, clock->offset); +} + static void clock_add(gpointer key, gpointer value, gpointer user_data) { struct clock_match *clock_match = user_data; @@ -81,15 +103,15 @@ static void clock_add(gpointer key, gpointer value, gpointer user_data) (gpointer) (unsigned long) v); if (!tc_clock) { /* - * For now, we only support CTF that has one - * single clock uuid or name (absolute ref). + * For now we only support CTF that has one + * single clock uuid or name (absolute ref) per + * trace. */ if (g_hash_table_size(tc_clocks) > 0) { fprintf(stderr, "[error] Only CTF traces with a single clock description are supported by this babeltrace version.\n"); } if (!clock_match->tc->offset_nr) { - clock_match->tc->offset_first = - (t_clock->offset_s * 1000000000ULL) + t_clock->offset; + clock_match->tc->offset_first = clock_offset_ns(t_clock); clock_match->tc->delta_offset_first_sum = 0; clock_match->tc->offset_nr++; clock_match->tc->single_clock_offset_avg = @@ -98,34 +120,32 @@ static void clock_add(gpointer key, gpointer value, gpointer user_data) g_hash_table_insert(tc_clocks, (gpointer) (unsigned long) v, value); - } else { + } else if (!t_clock->absolute) { int64_t diff_ns; /* - * Check that the offsets match. If not, warn - * the user that we do an arbitrary choice. + * For non-absolute clocks, check that the + * offsets match. If not, warn the user that we + * do an arbitrary choice. */ - diff_ns = tc_clock->offset_s; - diff_ns -= t_clock->offset_s; - diff_ns *= 1000000000ULL; - diff_ns += tc_clock->offset; - diff_ns -= t_clock->offset; + diff_ns = clock_offset_ns(tc_clock) - clock_offset_ns(t_clock); printf_debug("Clock \"%s\" offset between traces has a delta of %" PRIu64 " ns.", g_quark_to_string(tc_clock->name), diff_ns < 0 ? -diff_ns : diff_ns); - if (diff_ns > 10000) { + if (diff_ns > 10000 || diff_ns < -10000) { fprintf(stderr, "[warning] Clock \"%s\" offset differs between traces (delta %" PRIu64 " ns). Using average.\n", g_quark_to_string(tc_clock->name), diff_ns < 0 ? -diff_ns : diff_ns); } /* Compute average */ clock_match->tc->delta_offset_first_sum += - (t_clock->offset_s * 1000000000ULL) + t_clock->offset - - clock_match->tc->offset_first; + clock_offset_ns(t_clock) - clock_match->tc->offset_first; clock_match->tc->offset_nr++; clock_match->tc->single_clock_offset_avg = clock_match->tc->offset_first + (clock_match->tc->delta_offset_first_sum / clock_match->tc->offset_nr); + /* Time need to use offset average */ + clock_match->tc->clock_use_offset_avg = 1; } } }