From 297c08310f8455ee43842a6ce20829097bca1ece Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Tue, 2 Mar 2021 00:35:55 -0800
Subject: [PATCH] Enable BPF program instruction traces (#15613) (#15621)

(cherry picked from commit 3cd00965a78a91ad0bb00802d725750366ce3fb6)

Co-authored-by: Jack May <jack@solana.com>
---
 Cargo.lock                     |  1 +
 program-test/src/lib.rs        |  5 ++---
 programs/bpf_loader/Cargo.toml |  1 +
 programs/bpf_loader/src/lib.rs | 10 +++++++++-
 4 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 540aead96a..4bb3c6c58d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3945,6 +3945,7 @@ dependencies = [
  "bincode",
  "byteorder",
  "curve25519-dalek 3.0.0",
+ "log 0.4.11",
  "num-derive",
  "num-traits",
  "rand 0.7.3",
diff --git a/program-test/src/lib.rs b/program-test/src/lib.rs
index e55fe3cb91..2e7a1bcdbb 100644
--- a/program-test/src/lib.rs
+++ b/program-test/src/lib.rs
@@ -430,8 +430,7 @@ impl Default for ProgramTest {
     ///
     fn default() -> Self {
         solana_logger::setup_with_default(
-            "solana_bpf_loader=debug,\
-             solana_rbpf::vm=debug,\
+            "solana_rbpf::vm=debug,\
              solana_runtime::message_processor=debug,\
              solana_runtime::system_instruction_processor=trace,\
              solana_program_test=info",
@@ -523,7 +522,7 @@ impl ProgramTest {
     /// directory.
     ///
     /// If `process_instruction` is provided, the natively built-program may be used instead of the
-    /// BPF shared object depending on the `bpf` environment variable.
+    /// BPF shared object depending on the `BPF_OUT_DIR` environment variable.
     pub fn add_program(
         &mut self,
         program_name: &str,
diff --git a/programs/bpf_loader/Cargo.toml b/programs/bpf_loader/Cargo.toml
index 03e3213ffc..4ee36df97d 100644
--- a/programs/bpf_loader/Cargo.toml
+++ b/programs/bpf_loader/Cargo.toml
@@ -12,6 +12,7 @@ edition = "2018"
 bincode = "1.3.1"
 byteorder = "1.3.4"
 curve25519-dalek = "3"
+log = "0.4.11"
 num-derive = "0.3"
 num-traits = "0.2"
 rand_core = "0.6.2"
diff --git a/programs/bpf_loader/src/lib.rs b/programs/bpf_loader/src/lib.rs
index acdafe4f08..f6da242b89 100644
--- a/programs/bpf_loader/src/lib.rs
+++ b/programs/bpf_loader/src/lib.rs
@@ -14,6 +14,7 @@ use crate::{
     serialization::{deserialize_parameters, serialize_parameters},
     syscalls::SyscallError,
 };
+use log::{log_enabled, trace, Level::Trace};
 use solana_rbpf::{
     ebpf::MM_HEAP_START,
     error::{EbpfError, UserDefinedError},
@@ -83,7 +84,7 @@ pub fn create_and_cache_executor(
             max_call_depth: bpf_compute_budget.max_call_depth,
             stack_frame_size: bpf_compute_budget.stack_frame_size,
             enable_instruction_meter: true,
-            enable_instruction_tracing: false,
+            enable_instruction_tracing: log_enabled!(Trace),
         },
     )
     .map_err(|e| map_ebpf_error(invoke_context, e))?;
@@ -812,6 +813,13 @@ impl Executor for BpfExecutor {
                 before - after,
                 before
             );
+            if log_enabled!(Trace) {
+                let mut trace_buffer = String::new();
+                vm.get_tracer()
+                    .write(&mut trace_buffer, vm.get_program())
+                    .unwrap();
+                trace!("BPF Program Instruction Trace:\n{}", trace_buffer);
+            }
             match result {
                 Ok(status) => {
                     if status != SUCCESS {