Merge remote-tracking branch 'upstream/master' into protosplit

4 files changed, 490 insertions, 29 deletions

diff --git a/test/core/client_config/lb_policies_test.c b/test/core/client_config/lb_policies_test.c
index a9edf38157..3eb6f11bf7 100644
--- a/test/core/client_config/lb_policies_test.c
+++ b/test/core/client_config/lb_policies_test.c
@@ -211,29 +211,32 @@ static void teardown_servers(servers_fixture *f) {
   gpr_free(f);
 }
 
+typedef struct request_data {
+  grpc_metadata_array initial_metadata_recv;
+  grpc_metadata_array trailing_metadata_recv;
+  char *details;
+  size_t details_capacity;
+  grpc_status_code status;
+  grpc_call_details *call_details;
+} request_data;
+
 /** Returns connection sequence (server indices), which must be freed */
 int *perform_request(servers_fixture *f, grpc_channel *client,
-                     const test_spec *spec) {
+                     request_data *rdata, const test_spec *spec) {
   grpc_call *c;
   int s_idx;
   int *s_valid;
   gpr_timespec deadline;
   grpc_op ops[6];
   grpc_op *op;
-  grpc_status_code status;
-  char *details;
-  size_t details_capacity;
   int was_cancelled;
-  grpc_call_details *call_details;
   size_t i, iter_num;
   grpc_event ev;
   int read_tag;
   int *connection_sequence;
-  grpc_metadata_array initial_metadata_recv;
-  grpc_metadata_array trailing_metadata_recv;
 
   s_valid = gpr_malloc(sizeof(int) * f->num_servers);
-  call_details = gpr_malloc(sizeof(grpc_call_details) * f->num_servers);
+  rdata->call_details = gpr_malloc(sizeof(grpc_call_details) * f->num_servers);
   connection_sequence = gpr_malloc(sizeof(int) * spec->num_iters);
 
   /* Send a trivial request. */
@@ -241,8 +244,8 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
 
   for (iter_num = 0; iter_num < spec->num_iters; iter_num++) {
     cq_verifier *cqv = cq_verifier_create(f->cq);
-    details = NULL;
-    details_capacity = 0;
+    rdata->details = NULL;
+    rdata->details_capacity = 0;
     was_cancelled = 2;
 
     for (i = 0; i < f->num_servers; i++) {
@@ -255,11 +258,11 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
     }
 
     connection_sequence[iter_num] = -1;
-    grpc_metadata_array_init(&initial_metadata_recv);
-    grpc_metadata_array_init(&trailing_metadata_recv);
+    grpc_metadata_array_init(&rdata->initial_metadata_recv);
+    grpc_metadata_array_init(&rdata->trailing_metadata_recv);
 
     for (i = 0; i < f->num_servers; i++) {
-      grpc_call_details_init(&call_details[i]);
+      grpc_call_details_init(&rdata->call_details[i]);
     }
     memset(s_valid, 0, f->num_servers * sizeof(int));
 
@@ -278,15 +281,15 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_INITIAL_METADATA;
-    op->data.recv_initial_metadata = &initial_metadata_recv;
+    op->data.recv_initial_metadata = &rdata->initial_metadata_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
-    op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
-    op->data.recv_status_on_client.status = &status;
-    op->data.recv_status_on_client.status_details = &details;
-    op->data.recv_status_on_client.status_details_capacity = &details_capacity;
+    op->data.recv_status_on_client.trailing_metadata = &rdata->trailing_metadata_recv;
+    op->data.recv_status_on_client.status = &rdata->status;
+    op->data.recv_status_on_client.status_details = &rdata->details;
+    op->data.recv_status_on_client.status_details_capacity = &rdata->details_capacity;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -299,7 +302,7 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
       if (f->servers[i] != NULL) {
         GPR_ASSERT(GRPC_CALL_OK ==
                    grpc_server_request_call(f->servers[i], &f->server_calls[i],
-                                            &call_details[i],
+                                            &rdata->call_details[i],
                                             &f->request_metadata_recv[i], f->cq,
                                             f->cq, tag(1000 + (int)i)));
       }
@@ -348,11 +351,12 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
       cq_expect_completion(cqv, tag(1), 1);
       cq_verify(cqv);
 
-      GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-      GPR_ASSERT(0 == strcmp(details, "xyz"));
-      GPR_ASSERT(0 == strcmp(call_details[s_idx].method, "/foo"));
-      GPR_ASSERT(0 == strcmp(call_details[s_idx].host, "foo.test.google.fr"));
+      GPR_ASSERT(rdata->status == GRPC_STATUS_UNIMPLEMENTED);
+      GPR_ASSERT(0 == strcmp(rdata->details, "xyz"));
+      GPR_ASSERT(0 == strcmp(rdata->call_details[s_idx].method, "/foo"));
+      GPR_ASSERT(0 == strcmp(rdata->call_details[s_idx].host, "foo.test.google.fr"));
       GPR_ASSERT(was_cancelled == 1);
+    } else {
     }
 
     for (i = 0; i < f->num_servers; i++) {
@@ -361,20 +365,20 @@ int *perform_request(servers_fixture *f, grpc_channel *client,
       }
       grpc_metadata_array_destroy(&f->request_metadata_recv[i]);
     }
-    grpc_metadata_array_destroy(&initial_metadata_recv);
-    grpc_metadata_array_destroy(&trailing_metadata_recv);
+    grpc_metadata_array_destroy(&rdata->initial_metadata_recv);
+    grpc_metadata_array_destroy(&rdata->trailing_metadata_recv);
 
     cq_verifier_destroy(cqv);
 
     grpc_call_destroy(c);
 
     for (i = 0; i < f->num_servers; i++) {
-      grpc_call_details_destroy(&call_details[i]);
+      grpc_call_details_destroy(&rdata->call_details[i]);
     }
-    gpr_free(details);
+    gpr_free(rdata->details);
   }
 
-  gpr_free(call_details);
+  gpr_free(rdata->call_details);
   gpr_free(s_valid);
 
   return connection_sequence;
@@ -436,6 +440,7 @@ void run_spec(const test_spec *spec) {
   char *client_hostport;
   char *servers_hostports_str;
   int *actual_connection_sequence;
+  request_data rdata;
   servers_fixture *f = setup_servers("127.0.0.1", spec->num_servers);
 
   /* Create client. */
@@ -448,7 +453,7 @@ void run_spec(const test_spec *spec) {
   gpr_log(GPR_INFO, "Testing '%s' with servers=%s client=%s", spec->description,
           servers_hostports_str, client_hostport);
 
-  actual_connection_sequence = perform_request(f, client, spec);
+  actual_connection_sequence = perform_request(f, client, &rdata, spec);
 
   spec->verifier(f, client, actual_connection_sequence, spec->num_iters);
 
diff --git a/test/core/end2end/fixtures/h2_uchannel.c b/test/core/end2end/fixtures/h2_uchannel.c
new file mode 100644
index 0000000000..d1f9d38b82
--- /dev/null
+++ b/test/core/end2end/fixtures/h2_uchannel.c
@@ -0,0 +1,314 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "test/core/end2end/end2end_tests.h"
+
+#include <string.h>
+
+#include "src/core/channel/channel_args.h"
+#include "src/core/channel/client_channel.h"
+#include "src/core/channel/client_uchannel.h"
+#include "src/core/channel/connected_channel.h"
+#include "src/core/channel/http_client_filter.h"
+#include "src/core/channel/http_server_filter.h"
+#include "src/core/client_config/resolver_registry.h"
+#include "src/core/iomgr/tcp_client.h"
+#include "src/core/surface/channel.h"
+#include "src/core/surface/server.h"
+#include "src/core/transport/chttp2_transport.h"
+#include <grpc/support/alloc.h>
+#include <grpc/support/host_port.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/thd.h>
+#include <grpc/support/useful.h>
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+
+typedef struct {
+  grpc_connector base;
+  gpr_refcount refs;
+
+  grpc_closure *notify;
+  grpc_connect_in_args args;
+  grpc_connect_out_args *result;
+
+  grpc_endpoint *tcp;
+
+  grpc_mdctx *mdctx;
+
+  grpc_closure connected;
+} connector;
+
+static void connector_ref(grpc_connector *con) {
+  connector *c = (connector *)con;
+  gpr_ref(&c->refs);
+}
+
+static void connector_unref(grpc_exec_ctx *exec_ctx, grpc_connector *con) {
+  connector *c = (connector *)con;
+  if (gpr_unref(&c->refs)) {
+    grpc_mdctx_unref(c->mdctx);
+    gpr_free(c);
+  }
+}
+
+static void connected(grpc_exec_ctx *exec_ctx, void *arg, int success) {
+  connector *c = arg;
+  grpc_closure *notify;
+  grpc_endpoint *tcp = c->tcp;
+  if (tcp != NULL) {
+    c->result->transport = grpc_create_chttp2_transport(
+        exec_ctx, c->args.channel_args, tcp, c->mdctx, 1);
+    grpc_chttp2_transport_start_reading(exec_ctx, c->result->transport, NULL,
+                                        0);
+    GPR_ASSERT(c->result->transport);
+    c->result->filters = gpr_malloc(sizeof(grpc_channel_filter *));
+    c->result->filters[0] = &grpc_http_client_filter;
+    c->result->num_filters = 1;
+  } else {
+    memset(c->result, 0, sizeof(*c->result));
+  }
+  notify = c->notify;
+  c->notify = NULL;
+  notify->cb(exec_ctx, notify->cb_arg, 1);
+}
+
+static void connector_shutdown(grpc_exec_ctx *exec_ctx, grpc_connector *con) {}
+
+static void connector_connect(grpc_exec_ctx *exec_ctx, grpc_connector *con,
+                              const grpc_connect_in_args *args,
+                              grpc_connect_out_args *result,
+                              grpc_closure *notify) {
+  connector *c = (connector *)con;
+  GPR_ASSERT(c->notify == NULL);
+  GPR_ASSERT(notify->cb);
+  c->notify = notify;
+  c->args = *args;
+  c->result = result;
+  c->tcp = NULL;
+  grpc_closure_init(&c->connected, connected, c);
+  grpc_tcp_client_connect(exec_ctx, &c->connected, &c->tcp,
+                          args->interested_parties, args->addr, args->addr_len,
+                          args->deadline);
+}
+
+static const grpc_connector_vtable connector_vtable = {
+    connector_ref, connector_unref, connector_shutdown, connector_connect};
+
+typedef struct {
+  grpc_subchannel_factory base;
+  gpr_refcount refs;
+  grpc_mdctx *mdctx;
+  grpc_channel_args *merge_args;
+  grpc_channel *master;
+  grpc_subchannel **sniffed_subchannel;
+} subchannel_factory;
+
+static void subchannel_factory_ref(grpc_subchannel_factory *scf) {
+  subchannel_factory *f = (subchannel_factory *)scf;
+  gpr_ref(&f->refs);
+}
+
+static void subchannel_factory_unref(grpc_exec_ctx *exec_ctx,
+                                     grpc_subchannel_factory *scf) {
+  subchannel_factory *f = (subchannel_factory *)scf;
+  if (gpr_unref(&f->refs)) {
+    GRPC_CHANNEL_INTERNAL_UNREF(exec_ctx, f->master, "subchannel_factory");
+    grpc_channel_args_destroy(f->merge_args);
+    grpc_mdctx_unref(f->mdctx);
+    gpr_free(f);
+  }
+}
+
+static grpc_subchannel *subchannel_factory_create_subchannel(
+    grpc_exec_ctx *exec_ctx, grpc_subchannel_factory *scf,
+    grpc_subchannel_args *args) {
+  subchannel_factory *f = (subchannel_factory *)scf;
+  connector *c = gpr_malloc(sizeof(*c));
+  grpc_channel_args *final_args =
+      grpc_channel_args_merge(args->args, f->merge_args);
+  grpc_subchannel *s;
+  memset(c, 0, sizeof(*c));
+  c->base.vtable = &connector_vtable;
+  c->mdctx = f->mdctx;
+  grpc_mdctx_ref(c->mdctx);
+  gpr_ref_init(&c->refs, 1);
+  args->mdctx = f->mdctx;
+  args->args = final_args;
+  args->master = f->master;
+  s = grpc_subchannel_create(&c->base, args);
+  grpc_connector_unref(exec_ctx, &c->base);
+  grpc_channel_args_destroy(final_args);
+  *f->sniffed_subchannel = s;
+  return s;
+}
+
+static const grpc_subchannel_factory_vtable test_subchannel_factory_vtable = {
+    subchannel_factory_ref, subchannel_factory_unref,
+    subchannel_factory_create_subchannel};
+
+/* The evil twin of grpc_insecure_channel_create. It allows the test to use the
+ * custom-built sniffing subchannel_factory */
+grpc_channel *channel_create(const char *target, const grpc_channel_args *args,
+                             grpc_subchannel **sniffed_subchannel) {
+  grpc_channel *channel = NULL;
+#define MAX_FILTERS 1
+  const grpc_channel_filter *filters[MAX_FILTERS];
+  grpc_resolver *resolver;
+  subchannel_factory *f;
+  grpc_mdctx *mdctx = grpc_mdctx_create();
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  size_t n = 0;
+
+  filters[n++] = &grpc_client_channel_filter;
+  GPR_ASSERT(n <= MAX_FILTERS);
+
+  channel = grpc_channel_create_from_filters(&exec_ctx, target, filters, n,
+                                             args, mdctx, 1);
+
+  f = gpr_malloc(sizeof(*f));
+  f->sniffed_subchannel = sniffed_subchannel;
+  f->base.vtable = &test_subchannel_factory_vtable;
+  gpr_ref_init(&f->refs, 1);
+  grpc_mdctx_ref(mdctx);
+  f->mdctx = mdctx;
+  f->merge_args = grpc_channel_args_copy(args);
+  f->master = channel;
+  GRPC_CHANNEL_INTERNAL_REF(f->master, "test_subchannel_factory");
+  resolver = grpc_resolver_create(target, &f->base);
+  if (!resolver) {
+    return NULL;
+  }
+
+  grpc_client_channel_set_resolver(
+      &exec_ctx, grpc_channel_get_channel_stack(channel), resolver);
+  GRPC_RESOLVER_UNREF(&exec_ctx, resolver, "test_create");
+  grpc_subchannel_factory_unref(&exec_ctx, &f->base);
+
+  grpc_exec_ctx_finish(&exec_ctx);
+
+  return channel;
+}
+
+typedef struct micro_fullstack_fixture_data {
+  char *localaddr;
+  grpc_channel *master_channel;
+  grpc_subchannel *sniffed_subchannel;
+} micro_fullstack_fixture_data;
+
+static grpc_end2end_test_fixture chttp2_create_fixture_micro_fullstack(
+    grpc_channel_args *client_args, grpc_channel_args *server_args) {
+  grpc_end2end_test_fixture f;
+  int port = grpc_pick_unused_port_or_die();
+  micro_fullstack_fixture_data *ffd =
+      gpr_malloc(sizeof(micro_fullstack_fixture_data));
+  memset(&f, 0, sizeof(f));
+
+  gpr_join_host_port(&ffd->localaddr, "127.0.0.1", port);
+
+  f.fixture_data = ffd;
+  f.cq = grpc_completion_queue_create(NULL);
+
+  return f;
+}
+
+static void chttp2_init_client_micro_fullstack(grpc_end2end_test_fixture *f,
+                                               grpc_channel_args *client_args) {
+  micro_fullstack_fixture_data *ffd = f->fixture_data;
+  grpc_connectivity_state conn_state;
+  char *ipv4_localaddr;
+
+  gpr_asprintf(&ipv4_localaddr, "ipv4:%s", ffd->localaddr);
+  ffd->master_channel =
+      channel_create(ipv4_localaddr, client_args, &ffd->sniffed_subchannel);
+  gpr_free(ipv4_localaddr);
+  gpr_log(GPR_INFO, "MASTER CHANNEL %p ", ffd->master_channel);
+  /* the following will block. That's ok for this test */
+  conn_state = grpc_channel_check_connectivity_state(ffd->master_channel,
+                                                     1 /* try to connect */);
+  GPR_ASSERT(conn_state == GRPC_CHANNEL_IDLE);
+
+  /* here sniffed_subchannel should be ready to use */
+  GPR_ASSERT(conn_state == GRPC_CHANNEL_IDLE);
+  GPR_ASSERT(ffd->sniffed_subchannel != NULL);
+  f->client = grpc_client_uchannel_create(ffd->sniffed_subchannel, client_args);
+  grpc_client_uchannel_set_subchannel(f->client, ffd->sniffed_subchannel);
+  gpr_log(GPR_INFO, "CHANNEL WRAPPING SUBCHANNEL: %p(%p)", f->client,
+          ffd->sniffed_subchannel);
+
+  GPR_ASSERT(f->client);
+}
+
+static void chttp2_init_server_micro_fullstack(grpc_end2end_test_fixture *f,
+                                               grpc_channel_args *server_args) {
+  micro_fullstack_fixture_data *ffd = f->fixture_data;
+  if (f->server) {
+    grpc_server_destroy(f->server);
+  }
+  f->server = grpc_server_create(server_args, NULL);
+  grpc_server_register_completion_queue(f->server, f->cq, NULL);
+  GPR_ASSERT(grpc_server_add_insecure_http2_port(f->server, ffd->localaddr));
+  grpc_server_start(f->server);
+}
+
+static void chttp2_tear_down_micro_fullstack(grpc_end2end_test_fixture *f) {
+  micro_fullstack_fixture_data *ffd = f->fixture_data;
+  grpc_channel_destroy(ffd->master_channel);
+  ffd->master_channel = NULL;
+  gpr_free(ffd->localaddr);
+  gpr_free(ffd);
+}
+
+/* All test configurations */
+static grpc_end2end_test_config configs[] = {
+    {"chttp2/micro_fullstack", FEATURE_MASK_SUPPORTS_DELAYED_CONNECTION,
+     chttp2_create_fixture_micro_fullstack, chttp2_init_client_micro_fullstack,
+     chttp2_init_server_micro_fullstack, chttp2_tear_down_micro_fullstack},
+};
+
+int main(int argc, char **argv) {
+  size_t i;
+
+  grpc_test_init(argc, argv);
+  grpc_init();
+
+  for (i = 0; i < sizeof(configs) / sizeof(*configs); i++) {
+    grpc_end2end_tests(configs[i]);
+  }
+
+  grpc_shutdown();
+
+  return 0;
+}
diff --git a/test/core/end2end/gen_build_yaml.py b/test/core/end2end/gen_build_yaml.py
index 9988950a6e..af8f48576c 100755
--- a/test/core/end2end/gen_build_yaml.py
+++ b/test/core/end2end/gen_build_yaml.py
@@ -48,6 +48,7 @@ uds_fixture_options = default_unsecure_fixture_options._replace(dns_resolver=Fal
 END2END_FIXTURES = {
     'h2_fakesec': default_secure_fixture_options._replace(ci_mac=False),
     'h2_full': default_unsecure_fixture_options,
+    'h2_uchannel': default_unsecure_fixture_options,
     'h2_compress': default_unsecure_fixture_options,
     'h2_uds': uds_fixture_options,
     'h2_uds+poll': uds_fixture_options._replace(platforms=['linux']),
diff --git a/test/core/support/cpu_test.c b/test/core/support/cpu_test.c
new file mode 100644
index 0000000000..fa83878a15
--- /dev/null
+++ b/test/core/support/cpu_test.c
@@ -0,0 +1,141 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/* Test gpr per-cpu support:
+   gpr_cpu_num_cores()
+   gpr_cpu_current_cpu()
+*/
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/cpu.h>
+#include <grpc/support/log.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/thd.h>
+#include <grpc/support/time.h>
+#include <stdio.h>
+#include <string.h>
+#include "test/core/util/test_config.h"
+
+/* Test structure is essentially:
+   1) Figure out how many cores are present on the test system
+   2) Create 3 times that many threads
+   3) Have each thread do some amount of work (basically want to
+      gaurantee that all threads are running at once, and enough of them
+      to run on all cores).
+   4) Each thread checks what core it is running on, and marks that core
+      as "used" in the test.
+   5) Count number of "used" cores.
+
+   The test will fail if:
+   1) gpr_cpu_num_cores() == 0
+   2) Any result from gpr_cpu_current_cpu() >= gpr_cpu_num_cores()
+   3) Ideally, we would fail if not all cores were seen as used. Unfortunately,
+      this is only probabilistically true, and depends on the OS, it's
+      scheduler, etc. So we just print out an indication of how many were seen;
+      hopefully developers can use this to sanity check their system.
+*/
+
+/* Status shared across threads */
+struct cpu_test {
+  gpr_mu mu;
+  int nthreads;
+  gpr_uint32 ncores;
+  int is_done;
+  gpr_cv done_cv;
+  int *used; /* is this core used? */
+  int r;     /* random number */
+};
+
+static void worker_thread(void *arg) {
+  struct cpu_test *ct = (struct cpu_test *)arg;
+  gpr_uint32 cpu;
+  int r = 12345678;
+  int i, j;
+  for (i = 0; i < 1000 / GRPC_TEST_SLOWDOWN_FACTOR; i++) {
+    /* run for a bit - just calculate something random. */
+    for (j = 0; j < 1000000 / GRPC_TEST_SLOWDOWN_FACTOR; j++) {
+      r = (r * 17) & ((r - i) | (r * i));
+    }
+    cpu = gpr_cpu_current_cpu();
+    GPR_ASSERT(cpu < ct->ncores);
+    gpr_mu_lock(&ct->mu);
+    ct->used[cpu] = 1;
+    gpr_mu_unlock(&ct->mu);
+  }
+  gpr_mu_lock(&ct->mu);
+  ct->r = r; /* make it look like we care about r's value... */
+  ct->nthreads--;
+  if (ct->nthreads == 0) {
+    ct->is_done = 1;
+    gpr_cv_signal(&ct->done_cv);
+  }
+  gpr_mu_unlock(&ct->mu);
+}
+
+static void cpu_test(void) {
+  gpr_uint32 i;
+  int cores_seen = 0;
+  struct cpu_test ct;
+  gpr_thd_id thd;
+  ct.ncores = gpr_cpu_num_cores();
+  GPR_ASSERT(ct.ncores > 0);
+  ct.nthreads = (int)ct.ncores * 3;
+  ct.used = gpr_malloc(ct.ncores * sizeof(int));
+  memset(ct.used, 0, ct.ncores * sizeof(int));
+  gpr_mu_init(&ct.mu);
+  gpr_cv_init(&ct.done_cv);
+  ct.is_done = 0;
+  for (i = 0; i < ct.ncores * 3; i++) {
+    GPR_ASSERT(gpr_thd_new(&thd, &worker_thread, &ct, NULL));
+  }
+  gpr_mu_lock(&ct.mu);
+  while (!ct.is_done) {
+    gpr_cv_wait(&ct.done_cv, &ct.mu, gpr_inf_future(GPR_CLOCK_REALTIME));
+  }
+  gpr_mu_unlock(&ct.mu);
+  fprintf(stderr, "Saw cores [");
+  for (i = 0; i < ct.ncores; i++) {
+    if (ct.used[i]) {
+      fprintf(stderr, "%d,", i);
+      cores_seen++;
+    }
+  }
+  fprintf(stderr, "] (%d/%d)\n", cores_seen, ct.ncores);
+  gpr_free(ct.used);
+}
+
+int main(int argc, char *argv[]) {
+  grpc_test_init(argc, argv);
+  cpu_test();
+  return 0;
+}