Add --disable-feature option

Signed-off-by: Jiri Olsa <[email protected]>
olsajiri · Oct 22, 2023 · ff9fc4c · ff9fc4c
1 parent d1672f6
commit ff9fc4c
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Showing 4 changed files with 24 additions and 3 deletions.
diff --git a/src/bpffeature.cpp b/src/bpffeature.cpp
@@ -358,6 +358,12 @@ bool BPFfeature::has_kprobe_multi()
   if (has_kprobe_multi_.has_value())
     return *has_kprobe_multi_;
 
+  if (disable_feature_.find("kprobe_multi") != std::string::npos)
+  {
+    has_kprobe_multi_ = false;
+    return *has_kprobe_multi_;
+  }
+
   const char* sym = "ksys_read";
   DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_opts);
   int progfd, linkfd = -1;
@@ -413,6 +419,12 @@ bool BPFfeature::has_uprobe_multi()
   if (has_uprobe_multi_.has_value())
     return *has_uprobe_multi_;
 
+  if (disable_feature_.find("uprobe_multi") != std::string::npos)
+  {
+    has_uprobe_multi_ = false;
+    return *has_uprobe_multi_;
+  }
+
   LIBBPF_OPTS(bpf_prog_load_opts,
               load_opts,
               .expected_attach_type = static_cast<enum ::bpf_attach_type>(

diff --git a/src/bpffeature.h b/src/bpffeature.h
@@ -57,6 +57,7 @@ public:                                                                        \
 class BPFfeature
 {
 public:
+  BPFfeature(std::string disable_feature) : disable_feature_(disable_feature) { }
   BPFfeature() = default;
   virtual ~BPFfeature() = default;
 
@@ -142,6 +143,8 @@ class BPFfeature
       int* outfd = nullptr);
 
   BTF btf_ = BTF({ "vmlinux" });
+
+  std::string disable_feature_;
 };
 
 #undef DEFINE_PROG_TEST

diff --git a/src/bpftrace.h b/src/bpftrace.h
@@ -93,9 +93,9 @@ class WildcardException : public std::exception
 class BPFtrace
 {
 public:
-  BPFtrace(std::unique_ptr<Output> o = std::make_unique<TextOutput>(std::cout))
+  BPFtrace(std::unique_ptr<Output> o = std::make_unique<TextOutput>(std::cout), std::string disable_feature = "")
       : out_(std::move(o)),
-        feature_(std::make_unique<BPFfeature>()),
+        feature_(std::make_unique<BPFfeature>(disable_feature)),
         probe_matcher_(std::make_unique<ProbeMatcher>(this)),
         ncpus_(get_possible_cpus().size())
   {

diff --git a/src/main.cpp b/src/main.cpp
@@ -75,6 +75,7 @@ enum Options
   INCLUDE,
   EMIT_ELF,
   EMIT_LLVM,
+  DISABLE_FEATURE,
 };
 } // namespace
 
@@ -499,6 +500,7 @@ struct Args
   std::string output_elf;
   std::string output_llvm;
   std::string aot;
+  std::string disable_feature;
   OutputBufferConfig obc = OutputBufferConfig::UNSET;
   BuildMode build_mode = BuildMode::DYNAMIC;
   std::vector<std::string> include_dirs;
@@ -525,6 +527,7 @@ Args parse_args(int argc, char* argv[])
     option{ "no-warnings", no_argument, nullptr, Options::NO_WARNING },
     option{ "test", required_argument, nullptr, Options::TEST },
     option{ "aot", required_argument, nullptr, Options::AOT },
+    option{ "disable-feature", required_argument, nullptr, Options::DISABLE_FEATURE },
     option{ nullptr, 0, nullptr, 0 }, // Must be last
   };
 
@@ -564,6 +567,9 @@ Args parse_args(int argc, char* argv[])
         args.aot = optarg;
         args.build_mode = BuildMode::AHEAD_OF_TIME;
         break;
+      case Options::DISABLE_FEATURE: // --disable-feature
+        args.disable_feature = optarg;
+        break;
       case 'o':
         args.output_file = optarg;
         break;
@@ -797,7 +803,7 @@ int main(int argc, char* argv[])
 
   libbpf_set_print(libbpf_print);
 
-  BPFtrace bpftrace(std::move(output));
+  BPFtrace bpftrace(std::move(output), args.disable_feature);
   bool verify_llvm_ir = false;
 
   if (!args.cmd_str.empty())