[profile] in-process mergeing support (part-2)

(Part-1 merging API is in profile runtime)

This patch implements a portable file opening API
with exclusive access for the process. In-process
profile merge requires profile file update to be
atomic/fully sychronized.

llvm-svn: 271864

2 files changed, 75 insertions, 0 deletions

diff --git a/compiler-rt/test/profile/Inputs/instrprof-file_ex.c b/compiler-rt/test/profile/Inputs/instrprof-file_ex.c
new file mode 100644
index 00000000000..22e7555a13f
--- /dev/null
+++ b/compiler-rt/test/profile/Inputs/instrprof-file_ex.c
@@ -0,0 +1,59 @@
+/* This is a test case where the parent process forks 10
+ * children which contend to write to the same file. With
+ * file locking support, the data from each child should not
+ * be lost.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+extern FILE *lprofOpenFileEx(const char *);
+int main(int argc, char *argv[]) {
+  pid_t tid;
+  FILE *F;
+  const char *FN;
+  int child[10];
+  int c;
+  int i;
+
+  if (argc < 2) {
+    fprintf(stderr, "Requires one argument \n");
+    exit(1);
+  }
+  FN = argv[1];
+  truncate(FN, 0);
+
+  for (i = 0; i < 10; i++) {
+    c = fork();
+    // in child: 
+    if (c == 0) {
+      FILE *F = lprofOpenFileEx(FN);
+      if (!F) {
+        fprintf(stderr, "Can not open file %s from child\n", FN);
+        exit(1);
+      }
+      fseek(F, 0, SEEK_END);
+      fprintf(F, "Dump from Child %d\n", i + 11);
+      fclose(F);
+      exit(0);
+    } else {
+      child[i] = c;
+    }
+  }
+
+  // In parent
+  for (i = 0; i < 10; i++) {
+    int child_status;
+    if ((tid = waitpid(child[i], &child_status, 0) == -1))
+      break;
+  }
+  F = lprofOpenFileEx(FN);
+  if (!F) {
+    fprintf(stderr, "Can not open file %s from parent\n", FN);
+    exit(1);
+  }
+  fseek(F, 0, SEEK_END);
+  fprintf(F, "Dump from parent %d\n", i + 11);
+  return 0;
+}
diff --git a/compiler-rt/test/profile/Linux/instrprof-file_ex.test b/compiler-rt/test/profile/Linux/instrprof-file_ex.test
new file mode 100644
index 00000000000..af79b7398cc
--- /dev/null
+++ b/compiler-rt/test/profile/Linux/instrprof-file_ex.test
@@ -0,0 +1,16 @@
+RUN: mkdir -p %t.d
+RUN: %clang_profgen -fprofile-instr-generate %S/../Inputs/instrprof-file_ex.c -o %t
+RUN: %run %t %t.d/run.dump
+RUN: sort %t.d/run.dump | FileCheck %s
+
+CHECK: Dump from Child 11
+CHECK-NEXT: Dump from Child 12
+CHECK-NEXT: Dump from Child 13
+CHECK-NEXT: Dump from Child 14
+CHECK-NEXT: Dump from Child 15
+CHECK-NEXT: Dump from Child 16
+CHECK-NEXT: Dump from Child 17
+CHECK-NEXT: Dump from Child 18
+CHECK-NEXT: Dump from Child 19
+CHECK-NEXT: Dump from Child 20
+CHECK-NEXT: Dump from parent 21