[PATCH 1/2] powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n

Nicholas Piggin npiggin at gmail.com
Tue May 9 19:15:59 AEST 2023


With JUMP_LABEL=n, hcall_tracepoint_refcount's address is being tested
instead of its value. This results in the tracing slowpath always being
taken unnecessarily.

Fixes: 9a10ccb29c0a2 ("powerpc/pseries: move hcall_tracepoint_refcount out of .toc")
Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
 arch/powerpc/platforms/pseries/hvCall.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 35254ac7af5e..ca0674b0b683 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -91,6 +91,7 @@ BEGIN_FTR_SECTION;						\
 	b	1f;						\
 END_FTR_SECTION(0, 1);						\
 	LOAD_REG_ADDR(r12, hcall_tracepoint_refcount) ;		\
+	ld	r12,0(r12);					\
 	std	r12,32(r1);					\
 	cmpdi	r12,0;						\
 	bne-	LABEL;						\
-- 
2.40.1



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