diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-06-03 08:41:39 +0000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-06-17 00:09:08 +1000 |
| commit | 863771a28e27dc9eaeaa88cea300370d032f0e0f (patch) | |
| tree | a2b744fc7635c80ff653043735b35dea37c63dff /arch/powerpc/kernel/head_book3s_32.S | |
| parent | 7235bb3593781ed022d0714a73c2c0d8eb8a835f (diff) | |
powerpc/32s: Convert switch_mmu_context() to C
switch_mmu_context() does things that can easily be done in C.
For updating user segments, we have update_user_segments().
As mentionned in commit b5efec00b671 ("powerpc/32s: Move KUEP
locking/unlocking in C"), update_user_segments() has the loop
unrolled which is a significant performance gain.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/05c0875ad8220c03452c3a334946e207c6ca04d6.1622708530.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/head_book3s_32.S')
| -rw-r--r-- | arch/powerpc/kernel/head_book3s_32.S | 58 |
1 files changed, 0 insertions, 58 deletions
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 326262030279..db0e2dc25f86 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -1034,58 +1034,6 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE) rfi /* - * void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next); - * - * Set up the segment registers for a new context. - */ -_ENTRY(switch_mmu_context) - lwz r3,MMCONTEXTID(r4) - cmpwi cr0,r3,0 - blt- 4f - mulli r3,r3,897 /* multiply context by skew factor */ - rlwinm r3,r3,4,8,27 /* VSID = (context & 0xfffff) << 4 */ -#ifdef CONFIG_PPC_KUEP - oris r3, r3, SR_NX@h /* Set Nx */ -#endif -#ifdef CONFIG_PPC_KUAP - oris r3, r3, SR_KS@h /* Set Ks */ -#endif - li r0,NUM_USER_SEGMENTS - mtctr r0 - -#ifdef CONFIG_BDI_SWITCH - /* Context switch the PTE pointer for the Abatron BDI2000. - * The PGDIR is passed as second argument. - */ - lwz r4, MM_PGD(r4) - lis r5, abatron_pteptrs@ha - stw r4, abatron_pteptrs@l + 0x4(r5) -#endif -BEGIN_MMU_FTR_SECTION -#ifndef CONFIG_BDI_SWITCH - lwz r4, MM_PGD(r4) -#endif - tophys(r4, r4) - rlwinm r4, r4, 4, 0xffff01ff - mtspr SPRN_SDR1, r4 -END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE) - li r4,0 - isync -3: - mtsrin r3,r4 - addi r3,r3,0x111 /* next VSID */ - rlwinm r3,r3,0,8,3 /* clear out any overflow from VSID field */ - addis r4,r4,0x1000 /* address of next segment */ - bdnz 3b - sync - isync - blr -4: trap - EMIT_BUG_ENTRY 4b,__FILE__,__LINE__,0 - blr -EXPORT_SYMBOL(switch_mmu_context) - -/* * An undocumented "feature" of 604e requires that the v bit * be cleared before changing BAT values. * @@ -1282,9 +1230,3 @@ EXPORT_SYMBOL(empty_zero_page) .globl swapper_pg_dir swapper_pg_dir: .space PGD_TABLE_SIZE - -/* Room for two PTE pointers, usually the kernel and current user pointers - * to their respective root page table. - */ -abatron_pteptrs: - .space 8 |