MIPS: lib: Mark intrinsics notrace

commit aedcfbe0 upstream.

On certain MIPS32 devices, the ftrace tracer "function_graph" uses
__lshrdi3() during the capturing of trace data. ftrace then attempts to
trace __lshrdi3() which leads to infinite recursion and a stack overflow.
Fix this by marking __lshrdi3() as notrace. Mark the other compiler
intrinsics as notrace in case the compiler decides to use them in the
ftrace path.
Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: <linux-mips@linux-mips.org>
Cc: <linux-kernel@vger.kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/13354/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[ kamal: backport to 4.2-stable: no bswap[ds]i.c ]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

arch/mips/lib/ashldi3.c

@@ -2,7 +2,7 @@
 
 #include "libgcc.h"
 
-long long __ashldi3(long long u, word_type b)
+long long notrace __ashldi3(long long u, word_type b)
 {
 	DWunion uu, w;
 	word_type bm;

arch/mips/lib/ashrdi3.c

@@ -2,7 +2,7 @@
 
 #include "libgcc.h"
 
-long long __ashrdi3(long long u, word_type b)
+long long notrace __ashrdi3(long long u, word_type b)
 {
 	DWunion uu, w;
 	word_type bm;

arch/mips/lib/cmpdi2.c

@@ -2,7 +2,7 @@
 
 #include "libgcc.h"
 
-word_type __cmpdi2(long long a, long long b)
+word_type notrace __cmpdi2(long long a, long long b)
 {
 	const DWunion au = {
 		.ll = a

arch/mips/lib/lshrdi3.c

@@ -2,7 +2,7 @@
 
 #include "libgcc.h"
 
-long long __lshrdi3(long long u, word_type b)
+long long notrace __lshrdi3(long long u, word_type b)
 {
 	DWunion uu, w;
 	word_type bm;

arch/mips/lib/ucmpdi2.c

@@ -2,7 +2,7 @@
 
 #include "libgcc.h"
 
-word_type __ucmpdi2(unsigned long long a, unsigned long long b)
+word_type notrace __ucmpdi2(unsigned long long a, unsigned long long b)
 {
 	const DWunion au = {.ll = a};
 	const DWunion bu = {.ll = b};