Merging r195434:

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r195434 | eugenis | 2013-11-22 13:32:39 +0400 (Fri, 22 Nov 2013) | 4 lines

[sanitizer] Restore perf_event_attr handling.

This time in a forward/backward compatible way.

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git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/branches/release_34@195462 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 18 insertions, 4 deletions

diff --git a/lib/sanitizer_common/sanitizer_common_syscalls.inc b/lib/sanitizer_common/sanitizer_common_syscalls.inc
index 00a9c301d..958f12f84 100644
--- a/lib/sanitizer_common/sanitizer_common_syscalls.inc
+++ b/lib/sanitizer_common/sanitizer_common_syscalls.inc
@@ -2703,11 +2703,13 @@ PRE_SYSCALL(syncfs)(long fd) {}
 
 POST_SYSCALL(syncfs)(long res, long fd) {}
 
-PRE_SYSCALL(perf_event_open)(void *attr_uptr, long pid, long cpu, long group_fd,
-                             long flags) {}
+PRE_SYSCALL(perf_event_open)(__sanitizer_perf_event_attr *attr_uptr, long pid,
+                             long cpu, long group_fd, long flags) {
+  if (attr_uptr) PRE_READ(attr_uptr, attr_uptr->size);
+}
 
-POST_SYSCALL(perf_event_open)(long res, void *attr_uptr, long pid, long cpu,
-                              long group_fd, long flags) {}
+POST_SYSCALL(perf_event_open)(long res, __sanitizer_perf_event_attr *attr_uptr,
+                              long pid, long cpu, long group_fd, long flags) {}
 
 PRE_SYSCALL(mmap_pgoff)(long addr, long len, long prot, long flags, long fd,
                         long pgoff) {}
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_linux.cc b/lib/sanitizer_common/sanitizer_platform_limits_linux.cc
index c8f6c4005..bb9721b68 100644
--- a/lib/sanitizer_common/sanitizer_platform_limits_linux.cc
+++ b/lib/sanitizer_common/sanitizer_platform_limits_linux.cc
@@ -52,6 +52,13 @@ COMPILER_CHECK(struct_kernel_stat64_sz == sizeof(struct stat64));
 
 COMPILER_CHECK(struct_io_event_sz == sizeof(struct io_event));
 
+#if !SANITIZER_ANDROID
+COMPILER_CHECK(sizeof(struct __sanitizer_perf_event_attr) <=
+               sizeof(struct perf_event_attr));
+CHECK_SIZE_AND_OFFSET(perf_event_attr, type);
+CHECK_SIZE_AND_OFFSET(perf_event_attr, size);
+#endif
+
 COMPILER_CHECK(iocb_cmd_pread == IOCB_CMD_PREAD);
 COMPILER_CHECK(iocb_cmd_pwrite == IOCB_CMD_PWRITE);
 
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.h b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
index 84f9d3b18..1c4962058 100644
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.h
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -59,6 +59,11 @@ namespace __sanitizer {
   const unsigned struct_kernel_stat64_sz = 96;
 #endif
   const unsigned struct_io_event_sz = 32;
+  struct __sanitizer_perf_event_attr {
+    unsigned type;
+    unsigned size;
+    // More fields that vary with the kernel version.
+  };
 
   extern unsigned struct_utimbuf_sz;
   extern unsigned struct_new_utsname_sz;