Replace SSLProtocolNegotiation histogram with SSLNegotiatedAlpnProtocol.

net/socket/ssl_client_socket_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/socket/ssl_client_socket_impl.h"
 
 #include <errno.h>
 #include <openssl/bio.h>
 #include <openssl/bytestring.h>
 #include <openssl/err.h>
@@ skipping 1196 matching lines @@
     SSL_get0_alpn_selected(ssl_, &alpn_proto, &alpn_len);
     if (alpn_len > 0) {
       base::StringPiece proto(reinterpret_cast<const char*>(alpn_proto),
                               alpn_len);
       negotiated_protocol_ = NextProtoFromString(proto);
       npn_status_ = kNextProtoNegotiated;
       negotiation_extension_ = kExtensionALPN;
     }
   }
 
-  RecordNegotiationExtension();
+  RecordNegotiatedProtocol();
   RecordChannelIDSupport();
 
   const uint8_t* ocsp_response_raw;
   size_t ocsp_response_len;
   SSL_get0_ocsp_response(ssl_, &ocsp_response_raw, &ocsp_response_len);
   std::string ocsp_response;
   if (ocsp_response_len > 0) {
     ocsp_response_.assign(reinterpret_cast<const char*>(ocsp_response_raw),
                           ocsp_response_len);
   }
@@ skipping 1103 matching lines @@
 void SSLClientSocketImpl::LogConnectEndEvent(int rv) {
   if (rv != OK) {
     net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SSL_CONNECT, rv);
     return;
   }
 
   net_log_.EndEvent(NetLog::TYPE_SSL_CONNECT,
                     base::Bind(&NetLogSSLInfoCallback, base::Unretained(this)));
 }
 
-void SSLClientSocketImpl::RecordNegotiationExtension() const {
-  if (negotiation_extension_ == kExtensionUnknown)
-    return;
-  if (npn_status_ == kNextProtoUnsupported)
-    return;
-  base::HistogramBase::Sample sample =
-      static_cast<base::HistogramBase::Sample>(negotiated_protocol_);
-  // In addition to the protocol negotiated, we want to record which TLS
-  // extension was used, and in case of NPN, whether there was overlap between
-  // server and client list of supported protocols.
-  if (negotiation_extension_ == kExtensionNPN) {
-    if (npn_status_ == kNextProtoNoOverlap) {
-      sample += 1000;
-    } else {
-      sample += 500;
-    }
-  } else {
-    DCHECK_EQ(kExtensionALPN, negotiation_extension_);
-  }
-  UMA_HISTOGRAM_SPARSE_SLOWLY("Net.SSLProtocolNegotiation", sample);
+void SSLClientSocketImpl::RecordNegotiatedProtocol() const {
+  UMA_HISTOGRAM_ENUMERATION("SSL.AlpnNegotiatedProtocol", negotiated_protocol_,

[davidben, 2016/08/27 02:27:58]

We don't have much UMA that starts with "SSL." It's usually Net.SSLBlah (or
net.SSL_Blah, but that's apparently not the preferred style anymore.

Net.SSLNegotiatedAlpnProtocol?

[Bence, 2016/08/29 12:54:33]

I'm sorry, I have misunderstood your earlier comment at
https://crrev.com/2243453002/diff/40001/net/socket/ssl_client_socket_impl.cc#....
 My bad.

Done.

+                            kProtoNumberOfNextProtos);
 }
 
 void SSLClientSocketImpl::RecordChannelIDSupport() const {
   // Since this enum is used for a histogram, do not change or re-use values.
   enum {
     DISABLED = 0,
     CLIENT_ONLY = 1,
     CLIENT_AND_SERVER = 2,
     // CLIENT_NO_ECC is unused now.
     // CLIENT_BAD_SYSTEM_TIME is unused now.
@@ skipping 11 matching lines @@
   }
   UMA_HISTOGRAM_ENUMERATION("DomainBoundCerts.Support", supported,
                             CHANNEL_ID_USAGE_MAX);
 }
 
 bool SSLClientSocketImpl::IsChannelIDEnabled() const {
   return ssl_config_.channel_id_enabled && channel_id_service_;
 }
 
 }  // namespace net