From: Nicholas Piggin Date: Fri, 2 Aug 2019 10:56:59 +0000 (+1000) Subject: powerpc/64s/exception: program check handler do not branch into a macro X-Git-Tag: v5.4-rc1~99^2~85 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=1b3599829a2560fe6c9a5a4a6bb6b2bc4e5bdaee;p=linux.git powerpc/64s/exception: program check handler do not branch into a macro It is clever, but the small code saving is not worth the spaghetti of jumping to a label in an expanded macro, particularly when the label is just a number rather than a descriptive name. So expand the INT_COMMON macro twice, once for the stack and no stack cases, and branch to those. The slight code size increase is worth the improved clarity of branches for this non-performance critical code. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190802105709.27696-35-npiggin@gmail.com --- diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index aabd84e83615..b0649d56bb15 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -533,11 +533,10 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) andi. r10,r12,MSR_PR /* See if coming from user */ mr r10,r1 /* Save r1 */ subi r1,r1,INT_FRAME_SIZE /* alloc frame on kernel stack */ - beq- 1f + beq- 100f ld r1,PACAKSAVE(r13) /* kernel stack to use */ -1: tdgei r1,-INT_FRAME_SIZE /* trap if r1 is in userspace */ - EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0 -3: +100: tdgei r1,-INT_FRAME_SIZE /* trap if r1 is in userspace */ + EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,0 .endif std r9,_CCR(r1) /* save CR in stackframe */ @@ -551,10 +550,10 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) .if \kaup kuap_save_amr_and_lock r9, r10, cr1, cr0 .endif - beq 4f /* if from kernel mode */ + beq 101f /* if from kernel mode */ ACCOUNT_CPU_USER_ENTRY(r13, r9, r10) SAVE_PPR(\area, r9) -4: +101: .else .if \kaup kuap_save_amr_and_lock r9, r10, cr1 @@ -1325,9 +1324,11 @@ EXC_COMMON_BEGIN(program_check_common) mr r10,r1 /* Save r1 */ ld r1,PACAEMERGSP(r13) /* Use emergency stack */ subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */ - b 3f /* Jump into the macro !! */ + INT_COMMON 0x700, PACA_EXGEN, 0, 1, 1, 0, 0 + b 3f 2: INT_COMMON 0x700, PACA_EXGEN, 1, 1, 1, 0, 0 +3: bl save_nvgprs addi r3,r1,STACK_FRAME_OVERHEAD bl program_check_exception