| Message ID | 67c3b5d44edfec054234ea9b4d05fc4b4f7f8a0e.1664346554.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 0b4721815c5328e08c3acdee4a53890e012d830b |
| Headers | show |
| Series | powerpc/8xx: Reverse order entries are written by __set_pte_at() | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 10 jobs. |
| snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 10 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 6 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
On Wed, 28 Sep 2022 08:29:22 +0200, Christophe Leroy wrote: > At the time being, with 16k pages __set_pte_at() writes table entries > in reverse order: > > 294: 91 49 00 0c stw r10,12(r9) > 298: 91 49 00 08 stw r10,8(r9) > 29c: 91 49 00 04 stw r10,4(r9) > 2a0: 91 49 00 00 stw r10,0(r9) > > [...] Applied to powerpc/next. [1/1] powerpc/8xx: Reverse order entries are written by __set_pte_at() https://git.kernel.org/powerpc/c/0b4721815c5328e08c3acdee4a53890e012d830b cheers
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index 4fd73c7412d0..d2e39823af09 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -183,7 +183,7 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, * cases, and 32-bit non-hash with 32-bit PTEs. */ #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES) - ptep->pte = ptep->pte1 = ptep->pte2 = ptep->pte3 = pte_val(pte); + ptep->pte3 = ptep->pte2 = ptep->pte1 = ptep->pte = pte_val(pte); #else *ptep = pte; #endif
At the time being, with 16k pages __set_pte_at() writes table entries in reverse order: 294: 91 49 00 0c stw r10,12(r9) 298: 91 49 00 08 stw r10,8(r9) 29c: 91 49 00 04 stw r10,4(r9) 2a0: 91 49 00 00 stw r10,0(r9) Allthough there should be no impact at all as it stays in a single cacheline, reverse the writing in a more natural order. 288: 91 49 00 0c stw r10,0(r9) 28c: 91 49 00 08 stw r10,4(r9) 290: 91 49 00 04 stw r10,8(r9) 294: 91 49 00 00 stw r10,12(r9) Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- arch/powerpc/include/asm/nohash/pgtable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)