Commit 3f229f0e authored by Jim Harris's avatar Jim Harris
Browse files

app/trace: calculate per-core overlaps correctly 



Remove the calculation of g_last_tsc.  This was erroneously
cutting out valid data - for example, when reactor X has
an event that happened very early on, then reactor Y fills
its buffer before reactor X has another event.  All of reactor
Y's data would be ignored until reactor X processed another
event.

While here, remove some code that should have been removed
as part of the fudge_factor removal.  Also use SPDK_COUNTOF
to simplify calculation of the number of entries per
reactor buffer.

Reported-by: John Kariuki
Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I16c7f80cbfc8b4bb5f90a195d30df69e07b4ff85

Reviewed-on: https://review.gerrithub.io/424615


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent ea0afee0

app/trace/trace.cpp

+8 −22
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ 


extern "C" {

#include "spdk/trace.h"

#include "spdk/util.h"

}



static struct spdk_trace_histories *g_histories;
@@ -84,7 +85,6 @@ static int g_verbose = 1; 


static uint64_t g_tsc_rate;

static uint64_t g_first_tsc = 0x0;

static uint64_t g_last_tsc = -1ULL;



static float

get_us_from_tsc(uint64_t tsc, uint64_t tsc_rate)
@@ -212,15 +212,13 @@ process_event(struct spdk_trace_entry *e, uint64_t tsc_rate, 
static int

populate_events(struct spdk_trace_history *history)

{

	int i, entry_size, history_size, num_entries, num_entries_filled;

	int i, num_entries, num_entries_filled;

	struct spdk_trace_entry *e;

	int first, last, lcore;



	lcore = history->lcore;



	entry_size = sizeof(history->entries[0]);

	history_size = sizeof(history->entries);

	num_entries = history_size / entry_size;

	num_entries = SPDK_COUNTOF(history->entries);



	e = history->entries;
@@ -239,32 +237,20 @@ populate_events(struct spdk_trace_history *history) 
				last = i;

			}

		}



		if (first >= num_entries) {

			first -= num_entries;

		}



		if (last < 0) {

			last += num_entries;

		}

	} else {

		first = 0;

		last = num_entries_filled - 1;

	}



	/*

	 * We keep track of the highest first TSC out of all reactors and

	 *  the lowest last TSC out of all reactors.  We will ignore any

	 *  events outside the range of these two TSC values.  This will

	 *  ensure we only print data for the subset of time where we have

	 *  data across all reactors.

	 * We keep track of the highest first TSC out of all reactors.

	 *  We will ignore any events that occured before this TSC on any

	 *  other reactors.  This will ensure we only print data for the

	 *  subset of time where we have data across all reactors.

	 */

	if (e[first].tsc > g_first_tsc) {

		g_first_tsc = e[first].tsc;

	}

	if (e[last].tsc < g_last_tsc) {

		g_last_tsc = e[last].tsc;

	}



	i = first;

	while (1) {
@@ -416,7 +402,7 @@ int main(int argc, char **argv) 


	tsc_offset = g_first_tsc;

	for (entry_map::iterator it = g_entry_map.begin(); it != g_entry_map.end(); it++) {

		if (it->first.tsc < g_first_tsc || it->first.tsc > g_last_tsc) {

		if (it->first.tsc < g_first_tsc) {

			continue;

		}

		process_event(it->second, g_tsc_rate, tsc_offset, it->first.lcore);