[PATCH] mips: Fix build if PERF_EVENTS is configured

[Guenter Roeck <linux@roeck-us.net>]

mips builds fail in -next as follows if PERF_EVENTS is configured.

kernel/built-in.o: In function `perf_sample_regs_user':
kernel/events/core.c:4828: undefined reference to `perf_get_regs_user'

The problem is caused by commit 3478e32c1545 ("MIPS: Add user stack and
registers to perf.") in combination with commit 88a7c26af8da ("perf:
Move task_pt_regs sampling into arch code"), which introduces
perf_get_regs_user().

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: David Daney <david.daney@cavium.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
Compile tested only.

 arch/mips/kernel/perf_regs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/mips/kernel/perf_regs.c b/arch/mips/kernel/perf_regs.c
index 0451c4b..5b04454 100644
--- a/arch/mips/kernel/perf_regs.c
+++ b/arch/mips/kernel/perf_regs.c
@@ -58,3 +58,11 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
 
 	return (s64)v; /* Sign extend if 32-bit. */
 }
+
+void perf_get_regs_user(struct perf_regs *regs_user,
+			struct pt_regs *regs,
+			struct pt_regs *regs_user_copy)
+{
+	regs_user->regs = task_pt_regs(current);
+	regs_user->abi = perf_reg_abi(current);
+}
-- 
2.1.0