[dpdk-stable] [PATCH] event/sw: fix xstats reset value assignment bug

[Gage Eads <gage.eads@intel.com>]

The sw PMD implements xstats reset by having the xstat get operations
return a value to the statistic's value at the last reset. The value at the
last reset is maintained in the per-xstat reset_value field, but the PMD
was setting reset_value = current - reset_value instead of reset_value =
current.

Fixes: c1ad03df7ad5 ("event/sw: support xstats")
Cc: stable@dpdk.org

Signed-off-by: Gage Eads <gage.eads@intel.com>
---
 drivers/event/sw/sw_evdev_xstats.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/event/sw/sw_evdev_xstats.c b/drivers/event/sw/sw_evdev_xstats.c
index 7a6caa64d..90664903b 100644
--- a/drivers/event/sw/sw_evdev_xstats.c
+++ b/drivers/event/sw/sw_evdev_xstats.c
@@ -491,7 +491,7 @@ sw_xstats_update(struct sw_evdev *sw, enum rte_event_dev_xstats_mode mode,
 			values[xidx] = val;
 
 		if (xs->reset_allowed && reset)
-			xs->reset_value = val;
+			xs->reset_value += val;
 
 		xidx++;
 	}
@@ -544,8 +544,7 @@ sw_xstats_reset_range(struct sw_evdev *sw, uint32_t start, uint32_t num)
 		if (!xs->reset_allowed)
 			continue;
 
-		uint64_t val = xs->fn(sw, xs->obj_idx, xs->stat, xs->extra_arg)
-					- xs->reset_value;
+		uint64_t val = xs->fn(sw, xs->obj_idx, xs->stat, xs->extra_arg);
 		xs->reset_value = val;
 	}
 }
-- 
2.13.6