recordmcount: Remove uread()

uread() is only used to initialize the ELF file's pseudo
private-memory mapping while uwrite() and ulseek() work within
the pseudo-mapping and extend it as necessary.  Thus it is not
a complementary function to uwrite() and ulseek(). It also makes
no sense to do cleanups inside uread() when its only caller,
mmap_file(), is doing the relevant allocations and associated
initializations.

Therefore it's clearer to use a plain read() call to initialize the
data in mmap_file() and remove uread().

Link: http://lkml.kernel.org/r/31a87c22b19150cec1c8dc800c8b0873a2741703.1563992889.git.mhelsley@vmware.comSigned-off-by: Matt Helsley <mhelsley@vmware.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

scripts/recordmcount.c

@@ -89,7 +89,7 @@ succeed_file(void)
 	longjmp(jmpenv, SJ_SUCCEED);
 }
 
-/* ulseek, uread, ...:  Check return value for errors. */
+/* ulseek, uwrite, ...:  Check return value for errors. */
 
 static off_t
 ulseek(int const fd, off_t const offset, int const whence)
@@ -112,17 +112,6 @@ ulseek(int const fd, off_t const offset, int const whence)
 	return file_ptr - file_map;
 }
 
-static size_t
-uread(int const fd, void *const buf, size_t const count)
-{
-	size_t const n = read(fd, buf, count);
-	if (n != count) {
-		perror("read");
-		fail_file();
-	}
-	return n;
-}
-
 static size_t
 uwrite(int const fd, void const *const buf, size_t const count)
 {
@@ -298,7 +287,10 @@ static void *mmap_file(char const *fname)
 	if (file_map == MAP_FAILED) {
 		mmap_failed = 1;
 		file_map = umalloc(sb.st_size);
-		uread(fd_map, file_map, sb.st_size);
+		if (read(fd_map, file_map, sb.st_size) != sb.st_size) {
+			perror(fname);
+			fail_file();
+		}
 	}
 	close(fd_map);