The stats_get API was changed to signal a potential failure to read
stats. Furthermore, some PMDs are able to provide statistics even after
a removal event occurred.
Considering this, the fail-safe can try to access the latest statistics
of a PMD to improve statistics accuracy.
Attempt an ultimate statistics read on removal time; if that fails, use
the latest recorded snapshot.
Signed-off-by: Matan Azrad <ma...@mellanox.com>
---
drivers/net/failsafe/failsafe_ether.c | 19 +++++++++++++++++--
drivers/net/failsafe/failsafe_ops.c | 10 ++++++++--
drivers/net/failsafe/failsafe_private.h | 7 ++++++-
3 files changed, 31 insertions(+), 5 deletions(-)
diff --git a/drivers/net/failsafe/failsafe_ether.c
b/drivers/net/failsafe/failsafe_ether.c
index f4db423..df38360 100644
--- a/drivers/net/failsafe/failsafe_ether.c
+++ b/drivers/net/failsafe/failsafe_ether.c
@@ -35,6 +35,7 @@
#include <rte_flow.h>
#include <rte_flow_driver.h>
+#include <rte_cycles.h>
#include "failsafe_private.h"
@@ -312,9 +313,23 @@
static void
fs_dev_stats_save(struct sub_device *sdev)
{
+ struct rte_eth_stats stats;
+ int err;
+
+ /* Attempt to read current stats. */
+ err = rte_eth_stats_get(PORT_ID(sdev), &stats);
+ if (err) {
+ uint64_t cycles = sdev->stats_snapshot.cycles;
+
+ WARN("Could not access latest statistics from sub-device %d.\n",
+ SUB_ID(sdev));
+ if (cycles != 0)
+ WARN("Using latest snapshot taken before %lu
seconds.\n",
+ (rte_rdtsc() - cycles) / rte_get_tsc_hz());
+ }
failsafe_stats_increment(&PRIV(sdev->fs_dev)->stats_accumulator,
- &sdev->stats_snapshot);
- memset(&sdev->stats_snapshot, 0, sizeof(struct rte_eth_stats));
+ err ? &sdev->stats_snapshot.stats : &stats);
+ memset(&sdev->stats_snapshot, 0, sizeof(sdev->stats_snapshot));
}
static inline int
diff --git a/drivers/net/failsafe/failsafe_ops.c
b/drivers/net/failsafe/failsafe_ops.c
index d360965..818f12d 100644
--- a/drivers/net/failsafe/failsafe_ops.c
+++ b/drivers/net/failsafe/failsafe_ops.c
@@ -38,6 +38,7 @@
#include <rte_ethdev.h>
#include <rte_malloc.h>
#include <rte_flow.h>
+#include <rte_cycles.h>
#include "failsafe_private.h"
@@ -592,13 +593,18 @@
rte_memcpy(stats, &PRIV(dev)->stats_accumulator, sizeof(*stats));
FOREACH_SUBDEV_STATE(sdev, i, dev, DEV_ACTIVE) {
- ret = rte_eth_stats_get(PORT_ID(sdev), &sdev->stats_snapshot);
+ struct rte_eth_stats *snapshot = &sdev->stats_snapshot.stats;
+ uint64_t *cycles = &sdev->stats_snapshot.cycles;
+
+ ret = rte_eth_stats_get(PORT_ID(sdev), snapshot);
if (ret) {
ERROR("Operation rte_eth_stats_get failed for
sub_device %d with error %d",
i, ret);
+ *cycles = 0;
return ret;
}
- failsafe_stats_increment(stats, &sdev->stats_snapshot);
+ *cycles = rte_rdtsc();
+ failsafe_stats_increment(stats, snapshot);
}
return 0;
}
diff --git a/drivers/net/failsafe/failsafe_private.h
b/drivers/net/failsafe/failsafe_private.h
index d343ebf..1df52f4 100644
--- a/drivers/net/failsafe/failsafe_private.h
+++ b/drivers/net/failsafe/failsafe_private.h
@@ -93,6 +93,11 @@ enum dev_state {
DEV_STARTED,
};
+struct fs_stats {
+ struct rte_eth_stats stats;
+ uint64_t cycles;
+};
+
struct sub_device {
/* Exhaustive DPDK device description */
struct rte_devargs devargs;
@@ -103,7 +108,7 @@ struct sub_device {
/* Device state machine */
enum dev_state state;
/* Last stats snapshot passed to user */
- struct rte_eth_stats stats_snapshot;
+ struct fs_stats stats_snapshot;
/* Some device are defined as a command line */
char *cmdline;
/* fail-safe device backreference */
--
1.8.3.1
