diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2017-07-19 14:49:24 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-08-02 13:11:07 +1000 |
| commit | c433ec0455f921eaf8dd0262a718ce6f8ad62ea2 (patch) | |
| tree | 0ebadb7e7d100f4aebeb137ad04d09e96abbaff3 /arch/powerpc/mm | |
| parent | 7afad422ac61067473d5f3d20bbd5472af533bcd (diff) | |
powerpc/mm: Pre-filter SRR1 bits before do_page_fault()
By filtering the relevant SRR1 bits in the assembly rather than
in do_page_fault() itself, we avoid a conditional branch (since we
already come from different path for data and instruction faults).
This will allow more simplifications later
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/fault.c | 14 |
1 files changed, 2 insertions, 12 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index faddc87d0205..f04bc9f6b134 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -203,23 +203,13 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; int code = SEGV_MAPERR; int is_write = 0; - int trap = TRAP(regs); - int is_exec = trap == 0x400; + int is_exec = TRAP(regs) == 0x400; int is_user = user_mode(regs); int fault; int rc = 0, store_update_sp = 0; #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) - /* - * Fortunately the bit assignments in SRR1 for an instruction - * fault and DSISR for a data fault are mostly the same for the - * bits we are interested in. But there are some bits which - * indicate errors in DSISR but can validly be set in SRR1. - */ - if (is_exec) - error_code &= 0x48200000; - else - is_write = error_code & DSISR_ISSTORE; + is_write = error_code & DSISR_ISSTORE; #else is_write = error_code & ESR_DST; #endif /* CONFIG_4xx || CONFIG_BOOKE */ |