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[ovs-dev,v7,04/11] odp-execute: Add auto validation function for actions.

Message ID 20220614115409.1143269-2-emma.finn@intel.com
State Rejected
Headers show
Series None | expand

Commit Message

Emma Finn June 14, 2022, 11:54 a.m. UTC
This commit introduced the auto-validation function which
allows users to compare the batch of packets obtained from
different action implementations against the linear
action implementation.

The autovalidator function can be triggered at runtime using the
following command:

$ ovs-appctl dpif-netdev/action-impl-set autovalidator

Signed-off-by: Emma Finn <emma.finn@intel.com>
Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
---
 NEWS                      |  3 ++
 lib/dp-packet.c           | 23 +++++++++
 lib/dp-packet.h           |  4 ++
 lib/odp-execute-private.c | 98 +++++++++++++++++++++++++++++++++++++++
 lib/odp-execute-private.h |  6 +++
 5 files changed, 134 insertions(+)
diff mbox series

Patch

diff --git a/NEWS b/NEWS
index 9fe3f44f4..3a25f3035 100644
--- a/NEWS
+++ b/NEWS
@@ -32,6 +32,9 @@  Post-v2.17.0
    - DPDK:
      * OVS validated with DPDK 21.11.1.  It is recommended to use this version
        until further releases.
+   - Userspace datapath:
+     * Add actions auto-validator function to compare different actions
+       implementations against default implementation.
 
 
 v2.17.0 - 17 Feb 2022
diff --git a/lib/dp-packet.c b/lib/dp-packet.c
index 35c72542a..237dcf19e 100644
--- a/lib/dp-packet.c
+++ b/lib/dp-packet.c
@@ -506,3 +506,26 @@  dp_packet_resize_l2(struct dp_packet *b, int increment)
     dp_packet_adjust_layer_offset(&b->l2_5_ofs, increment);
     return dp_packet_data(b);
 }
+
+bool
+dp_packet_compare_offsets(struct dp_packet *b1, struct dp_packet *b2,
+                          struct ds *err_str)
+{
+    if ((b1->l2_pad_size != b2->l2_pad_size) ||
+        (b1->l2_5_ofs != b2->l2_5_ofs) ||
+        (b1->l3_ofs != b2->l3_ofs) ||
+        (b1->l4_ofs != b2->l4_ofs)) {
+            ds_put_format(err_str, "Packet offset comparison failed"
+                          "\n");
+            ds_put_format(err_str, "Buffer 1 offsets: l2_pad_size %u,"
+                          " l2_5_ofs : %u l3_ofs %u, l4_ofs %u\n",
+                          b1->l2_pad_size, b1->l2_5_ofs,
+                          b1->l3_ofs, b1->l4_ofs);
+            ds_put_format(err_str, "Buffer 2 offsets: l2_pad_size %u,"
+                          " l2_5_ofs : %u l3_ofs %u, l4_ofs %u\n",
+                          b2->l2_pad_size, b2->l2_5_ofs,
+                          b2->l3_ofs, b2->l4_ofs);
+        return false;
+    }
+    return true;
+}
diff --git a/lib/dp-packet.h b/lib/dp-packet.h
index bddaa2b5d..1776c3bfe 100644
--- a/lib/dp-packet.h
+++ b/lib/dp-packet.h
@@ -236,6 +236,10 @@  void *dp_packet_steal_data(struct dp_packet *);
 static inline bool dp_packet_equal(const struct dp_packet *,
                                    const struct dp_packet *);
 
+bool dp_packet_compare_offsets(struct dp_packet *good,
+                               struct dp_packet *test,
+                               struct ds *err_str);
+
 
 /* Frees memory that 'b' points to, as well as 'b' itself. */
 static inline void
diff --git a/lib/odp-execute-private.c b/lib/odp-execute-private.c
index 25dbbfefc..267f32c3e 100644
--- a/lib/odp-execute-private.c
+++ b/lib/odp-execute-private.c
@@ -28,8 +28,15 @@ 
 
 VLOG_DEFINE_THIS_MODULE(odp_execute_impl);
 static int active_action_impl_index;
+static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
 
 static struct odp_execute_action_impl action_impls[] = {
+    [ACTION_IMPL_AUTOVALIDATOR] = {
+        .available = false,
+        .name = "autovalidator",
+        .init_func = action_autoval_init,
+    },
+
     [ACTION_IMPL_SCALAR] = {
         .available = false,
         .name = "scalar",
@@ -94,3 +101,94 @@  odp_execute_action_init(void)
                   action_impls[i].name, avail ? "available" : "not available");
     }
 }
+
+/* Init sequence required to be scalar first to pick up the default scalar
+* implementations, allowing over-riding of the optimized functions later.
+*/
+BUILD_ASSERT_DECL(ACTION_IMPL_SCALAR == 0);
+BUILD_ASSERT_DECL(ACTION_IMPL_AUTOVALIDATOR == 1);
+
+/* Loop over packets, and validate each one for the given action. */
+static void
+action_autoval_generic(struct dp_packet_batch *batch, const struct nlattr *a)
+{
+    bool failed = false;
+    int type = nl_attr_type(a);
+    enum ovs_action_attr attr_type = (enum ovs_action_attr) type;
+    struct odp_execute_action_impl *scalar = &action_impls[ACTION_IMPL_SCALAR];
+    struct dp_packet_batch good_batch;
+
+    dp_packet_batch_clone(&good_batch, batch);
+
+    scalar->funcs[attr_type](&good_batch, a);
+
+    for (int impl = ACTION_IMPL_BEGIN; impl < ACTION_IMPL_MAX; impl++) {
+        /* Clone original batch and execute implementation under test. */
+        struct dp_packet_batch test_batch;
+
+        dp_packet_batch_clone(&test_batch, batch);
+        action_impls[impl].funcs[attr_type](&test_batch, a);
+
+        /* Loop over implementations, checking each one. */
+        for (int pidx = 0; pidx < batch->count; pidx++) {
+            struct dp_packet *good_pkt = good_batch.packets[pidx];
+            struct dp_packet *test_pkt = test_batch.packets[pidx];
+
+            struct ds log_msg = DS_EMPTY_INITIALIZER;
+
+            /* Compare packet length and payload contents. */
+            bool eq = dp_packet_equal(good_pkt, test_pkt);
+
+            if (!eq) {
+                ds_put_format(&log_msg, "Packet: %d\nAction : ", pidx);
+                format_odp_actions(&log_msg, a, a->nla_len, NULL);
+                ds_put_format(&log_msg, "\nGood hex:\n");
+                ds_put_hex_dump(&log_msg, dp_packet_data(good_pkt),
+                                dp_packet_size(good_pkt), 0, false);
+                ds_put_format(&log_msg, "Test hex:\n");
+                ds_put_hex_dump(&log_msg, dp_packet_data(test_pkt),
+                                dp_packet_size(test_pkt), 0, false);
+
+                failed = true;
+            }
+
+            /* Compare offsets and RSS */
+            if (!dp_packet_compare_offsets(good_pkt, test_pkt, &log_msg)) {
+                failed = true;
+            }
+
+            uint32_t good_hash = dp_packet_get_rss_hash(good_pkt);
+            uint32_t test_hash = dp_packet_get_rss_hash(test_pkt);
+
+            if (good_hash != test_hash) {
+                ds_put_format(&log_msg, "Autovalidation rss hash failed\n");
+                ds_put_format(&log_msg, "Good RSS hash : %u\n", good_hash);
+                ds_put_format(&log_msg, "Test RSS hash : %u\n", test_hash);
+
+                failed = true;
+            }
+
+            if (failed) {
+                VLOG_ERR_RL(&rl, "Autovalidation of %s failed. Details:\n%s",
+                            action_impls[impl].name, ds_cstr(&log_msg));
+                ds_destroy(&log_msg);
+                failed = false;
+            }
+        }
+        dp_packet_delete_batch(&test_batch, 1);
+    }
+    dp_packet_delete_batch(&good_batch, 1);
+
+    /* Apply the action to the original batch for continued processing. */
+    scalar->funcs[attr_type](batch, a);
+}
+
+int
+action_autoval_init(struct odp_execute_action_impl *self)
+{
+    /* Set function pointers for actions that can be applied directly, these
+     * are identified by OVS_ACTION_ATTR_*. */
+    self->funcs[OVS_ACTION_ATTR_POP_VLAN] = action_autoval_generic;
+
+    return 0;
+}
diff --git a/lib/odp-execute-private.h b/lib/odp-execute-private.h
index c5ab00b07..d3dc669d1 100644
--- a/lib/odp-execute-private.h
+++ b/lib/odp-execute-private.h
@@ -54,6 +54,7 @@  struct odp_execute_action_impl {
 /* Order of Actions implementations. */
 enum odp_execute_action_impl_idx {
     ACTION_IMPL_SCALAR,
+    ACTION_IMPL_AUTOVALIDATOR,
     /* See ACTION_IMPL_BEGIN below, for "first to-be-validated" impl.
      * Do not change the autovalidator position in this list without updating
      * the define below.
@@ -64,6 +65,9 @@  enum odp_execute_action_impl_idx {
 
 /* Index to start verifying implementations from. */
 BUILD_ASSERT_DECL(ACTION_IMPL_SCALAR == 0);
+BUILD_ASSERT_DECL(ACTION_IMPL_AUTOVALIDATOR == 1);
+
+#define ACTION_IMPL_BEGIN (ACTION_IMPL_AUTOVALIDATOR + 1)
 
 /* Odp execute init handles setting up the state of the actions functions at
  * initialization time. It cannot return errors, as it must always succeed in
@@ -76,6 +80,8 @@  void odp_execute_action_init(void);
  */
 int odp_action_scalar_init(struct odp_execute_action_impl *self);
 
+int action_autoval_init(struct odp_execute_action_impl *self);
+
 int odp_execute_action_set(const char *name,
                                struct odp_execute_action_impl *active);