[COMMITTED 2.24] Fix MIPS n64 readahead (bug 21026).

[COMMITTED 2.24] Fix MIPS n64 readahead (bug 21026).

[Aurelien Jarno]

From: Joseph Myers <joseph@codesourcery.com>

As noted in bug 20126, MIPS n64 uses an incorrect implementation of
readahead intended for 32-bit systems.  This patch adds a
syscalls.list entry to fix this.  An updated version of the
consolidation patch
<https://sourceware.org/ml/libc-alpha/2016-09/msg00527.html> could
remove this syscalls.list entry again.

Tested with compilation (only) for mips64; the nature of the syscall
doesn't allow for a glibc test to detect this issue.

	[BZ #21026]
	* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
	(readahead): New syscall entry.

(cherry picked from commit 30733525c6867c160261db1afade6326000f9f75)
---
 ChangeLog                                             | 6 ++++++
 sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 6e4696c7df..13f809d26f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2017-01-05  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #21026]
+	* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
+	(readahead): New syscall entry.
+
 2017-04-07  H.J. Lu  <hongjiu.lu@intel.com>
 
 	[BZ #21258]
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
index 890a74494a..26ab6d0b75 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
@@ -4,6 +4,8 @@ mmap		-	mmap		b:aniiii __mmap		mmap __mmap64 mmap64
 
 sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
 
+readahead	-	readahead	i:iii	__readahead	readahead
+
 prlimit		EXTRA	prlimit64	i:iipp	prlimit		prlimit64
 
 fanotify_mark	EXTRA	fanotify_mark	i:iiiis	fanotify_mark
-- 
2.11.0