Message ID | 1343647339-25576-12-git-send-email-aneesh.kumar@linux.vnet.ibm.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
On Mon, Jul 30, 2012 at 04:52:17PM +0530, Aneesh Kumar K.V wrote: > From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> > > The proto-VSID space is divided into two class > User: 0 to 2^(CONTEXT_BITS + USER_ESID_BITS) -1 > kernel: 2^(CONTEXT_BITS + USER_ESID_BITS) to 2^(VSID_BITS) - 1 > > With KERNEL_START at 0xc000000000000000, the proto vsid for > the kernel ends up with 0xc00000000 (36 bits). With 64TB > patchset we need to have kernel proto-VSID in the > [2^37 to 2^38 - 1] range due to the increased USER_ESID_BITS. This needs to be rolled in with the previous patch, otherwise you'll break bisection. > diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S > index db2cb3f..405d380 100644 > --- a/arch/powerpc/mm/slb_low.S > +++ b/arch/powerpc/mm/slb_low.S > @@ -57,8 +57,16 @@ _GLOBAL(slb_allocate_realmode) > _GLOBAL(slb_miss_kernel_load_linear) > li r11,0 > BEGIN_FTR_SECTION > + li r9,0x1 > + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 > b slb_finish_load > END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) > + li r9,0x1 > + /* > + * shift 12 bits less here, slb_finish_load_1T will do > + * the necessary shits > + */ > + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 > b slb_finish_load_1T Since you're actually doing exactly the same instructions in the 256M and 1T segment cases, why not do the li; rldimi before the BEGIN_FTR_SECTION? > @@ -86,8 +94,16 @@ _GLOBAL(slb_miss_kernel_load_vmemmap) > li r11,0 > 6: > BEGIN_FTR_SECTION > + li r9,0x1 > + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 > b slb_finish_load > END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) > + li r9,0x1 > + /* > + * shift 12 bits less here, slb_finish_load_1T will do > + * the necessary shits > + */ > + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 > b slb_finish_load_1T And similarly here. Paul.
Paul Mackerras <paulus@samba.org> writes: > On Mon, Jul 30, 2012 at 04:52:17PM +0530, Aneesh Kumar K.V wrote: >> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> >> >> The proto-VSID space is divided into two class >> User: 0 to 2^(CONTEXT_BITS + USER_ESID_BITS) -1 >> kernel: 2^(CONTEXT_BITS + USER_ESID_BITS) to 2^(VSID_BITS) - 1 >> >> With KERNEL_START at 0xc000000000000000, the proto vsid for >> the kernel ends up with 0xc00000000 (36 bits). With 64TB >> patchset we need to have kernel proto-VSID in the >> [2^37 to 2^38 - 1] range due to the increased USER_ESID_BITS. > > This needs to be rolled in with the previous patch, otherwise you'll > break bisection. > >> diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S >> index db2cb3f..405d380 100644 >> --- a/arch/powerpc/mm/slb_low.S >> +++ b/arch/powerpc/mm/slb_low.S >> @@ -57,8 +57,16 @@ _GLOBAL(slb_allocate_realmode) >> _GLOBAL(slb_miss_kernel_load_linear) >> li r11,0 >> BEGIN_FTR_SECTION >> + li r9,0x1 >> + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 >> b slb_finish_load >> END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) >> + li r9,0x1 >> + /* >> + * shift 12 bits less here, slb_finish_load_1T will do >> + * the necessary shits >> + */ >> + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 >> b slb_finish_load_1T > > Since you're actually doing exactly the same instructions in the 256M > and 1T segment cases, why not do the li; rldimi before the > BEGIN_FTR_SECTION? > >> @@ -86,8 +94,16 @@ _GLOBAL(slb_miss_kernel_load_vmemmap) >> li r11,0 >> 6: >> BEGIN_FTR_SECTION >> + li r9,0x1 >> + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 >> b slb_finish_load >> END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) >> + li r9,0x1 >> + /* >> + * shift 12 bits less here, slb_finish_load_1T will do >> + * the necessary shits >> + */ >> + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 >> b slb_finish_load_1T > > And similarly here. > Folded to the previous patch and updated -aneesh
diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h index daa3e4b..8e97715 100644 --- a/arch/powerpc/include/asm/mmu-hash64.h +++ b/arch/powerpc/include/asm/mmu-hash64.h @@ -516,9 +516,19 @@ typedef struct { /* This is only valid for addresses >= PAGE_OFFSET */ static inline unsigned long get_kernel_vsid(unsigned long ea, int ssize) { - if (ssize == MMU_SEGSIZE_256M) - return vsid_scramble(ea >> SID_SHIFT, 256M); - return vsid_scramble(ea >> SID_SHIFT_1T, 1T); + unsigned long proto_vsid; + /* + * We need to make sure proto_vsid for the kernel is + * >= 2^(CONTEXT_BITS + USER_ESID_BITS[_1T]) + */ + if (ssize == MMU_SEGSIZE_256M) { + proto_vsid = ea >> SID_SHIFT; + proto_vsid |= (1UL << (CONTEXT_BITS + USER_ESID_BITS)); + return vsid_scramble(proto_vsid, 256M); + } + proto_vsid = ea >> SID_SHIFT_1T; + proto_vsid |= (1UL << (CONTEXT_BITS + USER_ESID_BITS_1T)); + return vsid_scramble(proto_vsid, 1T); } /* Returns the segment size indicator for a user address */ diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 1c06d29..40ed208 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -958,7 +958,9 @@ _GLOBAL(do_stab_bolted) rldimi r10,r11,7,52 /* r10 = first ste of the group */ /* Calculate VSID */ - /* This is a kernel address, so protovsid = ESID */ + /* This is a kernel address, so protovsid = ESID | 1 << 37 */ + li r9,0x1 + rldimi r11,r9,(CONTEXT_BITS + USER_ESID_BITS),0 ASM_VSID_SCRAMBLE(r11, r9, 256M) rldic r9,r11,12,16 /* r9 = vsid << 12 */ diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S index db2cb3f..405d380 100644 --- a/arch/powerpc/mm/slb_low.S +++ b/arch/powerpc/mm/slb_low.S @@ -57,8 +57,16 @@ _GLOBAL(slb_allocate_realmode) _GLOBAL(slb_miss_kernel_load_linear) li r11,0 BEGIN_FTR_SECTION + li r9,0x1 + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 b slb_finish_load END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) + li r9,0x1 + /* + * shift 12 bits less here, slb_finish_load_1T will do + * the necessary shits + */ + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 b slb_finish_load_1T 1: @@ -86,8 +94,16 @@ _GLOBAL(slb_miss_kernel_load_vmemmap) li r11,0 6: BEGIN_FTR_SECTION + li r9,0x1 + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 b slb_finish_load END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT) + li r9,0x1 + /* + * shift 12 bits less here, slb_finish_load_1T will do + * the necessary shits + */ + rldimi r10,r9,(CONTEXT_BITS + USER_ESID_BITS),0 b slb_finish_load_1T 0: /* user address: proto-VSID = context << 15 | ESID. First check