Various minor fixes in the client:

- Don't call setrlimit() (it was needed to make 32-bit JVMs work with >3GB heaps)
- Remove a non-functional way to tweak the Linux scheduler
- Cosmetic fixes

--
MOS_MIGRATED_REVID=132653426

3 files changed, 7 insertions, 41 deletions

diff --git a/src/main/cpp/blaze.cc b/src/main/cpp/blaze.cc
index 833d9087e2..25eae2f166 100644
--- a/src/main/cpp/blaze.cc
+++ b/src/main/cpp/blaze.cc
@@ -1510,14 +1510,10 @@ static ATTRIBUTE_NORETURN void SendServerRequest(BlazeServer* server) {
       StartServerAndConnect(server);
     }
 
-    // Check for deleted server cwd:
+    // Check for the case when the workspace directory deleted and then gets
+    // recreated while the server is running
+
     string server_cwd = GetProcessCWD(globals->server_pid);
-    // TODO(bazel-team): Is this check even necessary? If someone deletes or
-    // moves the server directory, the client cannot connect to the server
-    // anymore. IOW, the client finds the server based on the output base,
-    // so if a server is found, it should be by definition at the correct output
-    // base.
-    //
     // If server_cwd is empty, GetProcessCWD failed. This notably occurs when
     // running under Docker because then readlink(/proc/[pid]/cwd) returns
     // EPERM.
@@ -1722,26 +1718,6 @@ static void SetupStreams() {
   if (fcntl(2, F_GETFL) == -1) open("/dev/null", O_WRONLY);
 }
 
-// Set an 8MB stack for Blaze. When the stack max is unbounded, it changes the
-// layout in the JVM's address space, and we are unable to instantiate the
-// default 3000MB heap.
-static void EnsureFiniteStackLimit() {
-  struct rlimit limit;
-  const int default_stack = 8 * 1024 * 1024;  // 8MB.
-  if (getrlimit(RLIMIT_STACK, &limit)) {
-    pdie(blaze_exit_code::LOCAL_ENVIRONMENTAL_ERROR, "getrlimit() failed");
-  }
-
-  if (default_stack < limit.rlim_cur) {
-    limit.rlim_cur = default_stack;
-    if (setrlimit(RLIMIT_STACK, &limit)) {
-      perror("setrlimit() failed: If the stack limit is too high, "
-             "this can cause the JVM to be unable to allocate enough "
-             "contiguous address space for its heap");
-    }
-  }
-}
-
 static void CheckBinaryPath(const string& argv0) {
   if (argv0[0] == '/') {
     globals->binary_path = argv0;
@@ -1842,7 +1818,6 @@ int Main(int argc, const char *argv[], OptionProcessor *option_processor) {
   globals->command_wait_time = blaze_server->AcquireLock();
 
   WarnFilesystemType(globals->options->output_base);
-  EnsureFiniteStackLimit();
 
   ExtractData(self_path);
   VerifyJavaVersionAndSetJvm();
diff --git a/src/main/cpp/blaze_util.cc b/src/main/cpp/blaze_util.cc
index 84c69a899f..6ba27b5165 100644
--- a/src/main/cpp/blaze_util.cc
+++ b/src/main/cpp/blaze_util.cc
@@ -421,9 +421,7 @@ uint64_t AcquireLock(const string& output_base, bool batch_mode, bool block,
   }
 
   // Identify ourselves in the lockfile.
-  if (ftruncate(lockfd, 0)) {
-    // Placate the compiler.
-  }
+  (void) ftruncate(lockfd, 0);
   const char *tty = ttyname(STDIN_FILENO);  // NOLINT (single-threaded)
   string msg = "owner=launcher\npid="
       + ToString(getpid()) + "\ntty=" + (tty ? tty : "") + "\n";
diff --git a/src/main/cpp/blaze_util_linux.cc b/src/main/cpp/blaze_util_linux.cc
index b94b79fae8..4bc2224dc9 100644
--- a/src/main/cpp/blaze_util_linux.cc
+++ b/src/main/cpp/blaze_util_linux.cc
@@ -14,6 +14,7 @@
 
 #include <errno.h>  // errno, ENAMETOOLONG
 #include <limits.h>
+#include <linux/magic.h>
 #include <pwd.h>
 #include <signal.h>
 #include <stdio.h>
@@ -72,7 +73,7 @@ void WarnFilesystemType(const string& output_base) {
     return;
   }
 
-  if (buf.f_type == 0x00006969) {  // NFS_SUPER_MAGIC
+  if (buf.f_type == NFS_SUPER_MAGIC) {
     fprintf(stderr, "WARNING: Output base '%s' is on NFS. This may lead "
             "to surprising failures and undetermined behavior.\n",
             output_base.c_str());
@@ -117,14 +118,6 @@ uint64_t ProcessClock() {
 }
 
 void SetScheduling(bool batch_cpu_scheduling, int io_nice_level) {
-  // Move ourself into a low priority CPU scheduling group if the
-  // machine is configured appropriately.  Fail silently, because this
-  // isn't available on all kernels.
-  if (FILE *f = fopen("/dev/cgroup/cpu/batch/tasks", "w")) {
-    fprintf(f, "%d", getpid());
-    fclose(f);
-  }
-
   if (batch_cpu_scheduling) {
     sched_param param = {};
     param.sched_priority = 0;
@@ -280,7 +273,7 @@ bool KillServerProcess(
       &recorded_start_time);
 
   // start time file got deleted, but PID file didn't. This is strange.
-  // Assume that this is an old Blaze process that doesn't know how to  write
+  // Assume that this is an old Blaze process that doesn't know how to write
   // start time files yet.
   if (file_present && recorded_start_time != start_time) {
     // This is a different process.