Support collecting gRPC core metrics

.github/workflows/ci.yml

@@ -3,7 +3,7 @@ name: CI
 on:
   pull_request:
   push:
-    branches: 
+    branches:
     - master
     - v0.*
   schedule:
@@ -33,7 +33,7 @@ jobs:
       matrix:
         include:
           - host: ubuntu-latest
-            profile: 
+            profile:
             suffix:
     name: Linux-Stable${{ matrix.suffix }}
     runs-on: ${{ matrix.host }}
@@ -57,7 +57,7 @@ jobs:
       matrix:
         include:
           - host: ubuntu-latest
-            profile: 
+            profile:
             suffix:
     name: Linux-Stable-openssl${{ matrix.suffix }}
     runs-on: ${{ matrix.host }}
@@ -124,12 +124,12 @@ jobs:
     - uses: actions/checkout@v2
     - run: choco install -y llvm
     - run: Import-Module $env:ChocolateyInstall\helpers\chocolateyProfile.psm1
-    - run: go version ; cargo version ; cmake --version 
+    - run: go version ; cargo version ; cmake --version
     - run: cargo xtask submodule
     - run: cargo build
     - run: cargo test --all
     - run: cargo test --features "nightly"
-  
+
   Pre-Release:
     name: Pre-Release
     runs-on: ubuntu-latest

Cargo.toml

@@ -50,6 +50,7 @@ boringssl = ["grpcio-sys/boringssl", "_secure"]
 openssl = ["_secure", "grpcio-sys/openssl"]
 openssl-vendored = ["_secure", "grpcio-sys/openssl-vendored"]
 no-omit-frame-pointer = ["grpcio-sys/no-omit-frame-pointer"]
+internals = ["grpcio-sys/internals"]
 
 [badges]
 travis-ci = { repository = "tikv/grpc-rs" }

grpc-sys/Cargo.toml

@@ -64,8 +64,9 @@ openssl = ["_secure"]
 openssl-vendored = ["openssl", "openssl-sys"]
 no-omit-frame-pointer = []
 # A hidden feature that is used to force regenerating bindings.
-_gen-bindings = ["bindgen"]
+_gen-bindings = ["bindgen", "internals"]
 _list-package = []
+internals = []
 
 [target.'cfg(not(all(any(target_os = "linux", target_os = "macos"), any(target_arch = "x86_64", target_arch = "aarch64"))))'.build-dependencies]
 bindgen = "0.59.0"

grpc-sys/bindings/binding_internals.rs

@@ -0,0 +1,78 @@
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct grpcwrap_stats {
+    _unused: [u8; 0],
+}
+#[repr(u32)]
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+pub enum grpcwrap_stats_counter {
+    ClientCallsCreated = 0,
+    ServerCallsCreated = 1,
+    ClientChannelsCreated = 2,
+    ClientSubchannelsCreated = 3,
+    ServerChannelsCreated = 4,
+    InsecureConnectionsCreated = 5,
+    SyscallWrite = 6,
+    SyscallRead = 7,
+    TcpReadAlloc8k = 8,
+    TcpReadAlloc64k = 9,
+    Http2SettingsWrites = 10,
+    Http2PingsSent = 11,
+    Http2WritesBegun = 12,
+    Http2TransportStalls = 13,
+    Http2StreamStalls = 14,
+    CqPluckCreates = 15,
+    CqNextCreates = 16,
+    CqCallbackCreates = 17,
+    COUNTER_COUNT = 18,
+}
+#[repr(u32)]
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+pub enum grpcwrap_stats_histogram {
+    CallInitialSize = 0,
+    TcpWriteSize = 1,
+    TcpWriteIovSize = 2,
+    TcpReadSize = 3,
+    TcpReadOffer = 4,
+    TcpReadOfferIovSize = 5,
+    Http2SendMessageSize = 6,
+    Http2MetadataSize = 7,
+    HISTOGRAM_COUNT = 8,
+}
+extern "C" {
+    pub fn grpcwrap_stats_collect() -> *mut grpcwrap_stats;
+}
+extern "C" {
+    pub fn grpcwrap_stats_free(stats: *mut grpcwrap_stats);
+}
+extern "C" {
+    pub fn grpcwrap_stats_get_counter(
+        stats: *const grpcwrap_stats,
+        which: grpcwrap_stats_counter,
+    ) -> u64;
+}
+extern "C" {
+    pub fn grpcwrap_stats_counter_name(which: grpcwrap_stats_counter) -> grpc_slice;
+}
+extern "C" {
+    pub fn grpcwrap_stats_counter_doc(which: grpcwrap_stats_counter) -> grpc_slice;
+}
+extern "C" {
+    pub fn grpcwrap_stats_get_histogram_percentile(
+        stats: *const grpcwrap_stats,
+        which: grpcwrap_stats_histogram,
+        percentile: f64,
+    ) -> f64;
+}
+extern "C" {
+    pub fn grpcwrap_stats_get_histogram_count(
+        stats: *const grpcwrap_stats,
+        which: grpcwrap_stats_histogram,
+    ) -> f64;
+}
+extern "C" {
+    pub fn grpcwrap_stats_histogram_name(which: grpcwrap_stats_histogram) -> grpc_slice;
+}
+extern "C" {
+    pub fn grpcwrap_stats_histogram_doc(which: grpcwrap_stats_histogram) -> grpc_slice;
+}