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| author | Nicholas Piggin <npiggin@gmail.com> | 2019-08-02 20:56:59 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-08-30 11:14:58 +1000 |
| commit | 1b3599829a2560fe6c9a5a4a6bb6b2bc4e5bdaee (patch) | |
| tree | d337ded1606b6de5705a0724eeb70aebfe084251 | |
| parent | c7c5cbb42d6e207a059c64740b1654376619345e (diff) | |
| download | linux-1b3599829a2560fe6c9a5a4a6bb6b2bc4e5bdaee.tar.bz2 | |
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 <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-35-npiggin@gmail.com
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 15 |
1 files changed, 8 insertions, 7 deletions
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 |