From 1bec4adcd59e923df6b7f5d492a9e4b8dfd22039 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 11 Jul 2023 17:59:14 +0200 Subject: powerpc/kuap: Avoid useless jump_label on empty function Disassembly of interrupt_enter_prepare() shows a pointless nop before the mftb c000abf0 : c000abf0: 81 23 00 84 lwz r9,132(r3) c000abf4: 71 29 40 00 andi. r9,r9,16384 c000abf8: 41 82 00 28 beq- c000ac20 c000abfc: ===> 60 00 00 00 nop <==== c000ac00: 7d 0c 42 e6 mftb r8 c000ac04: 80 e2 00 08 lwz r7,8(r2) c000ac08: 81 22 00 28 lwz r9,40(r2) c000ac0c: 91 02 00 24 stw r8,36(r2) c000ac10: 7d 29 38 50 subf r9,r9,r7 c000ac14: 7d 29 42 14 add r9,r9,r8 c000ac18: 91 22 00 08 stw r9,8(r2) c000ac1c: 4e 80 00 20 blr c000ac20: 60 00 00 00 nop c000ac24: 7d 5a c2 a6 mfmd_ap r10 c000ac28: 3d 20 de 00 lis r9,-8704 c000ac2c: 91 43 00 b0 stw r10,176(r3) c000ac30: 7d 3a c3 a6 mtspr 794,r9 c000ac34: 4e 80 00 20 blr That comes from the call to kuap_loc(), allthough __kuap_lock() is an empty function on the 8xx. To avoid that, only perform kuap_is_disabled() check when there is something to do with __kuap_lock(). Do the same with __kuap_save_and_lock() and __kuap_get_and_assert_locked(). Signed-off-by: Christophe Leroy Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/a854d25bea375d4ba6ca9c2617f9edbba397100a.1689091022.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/book3s/32/kup.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/include/asm/book3s/32/kup.h') diff --git a/arch/powerpc/include/asm/book3s/32/kup.h b/arch/powerpc/include/asm/book3s/32/kup.h index 678f9c9d89b6..466a19cfb4df 100644 --- a/arch/powerpc/include/asm/book3s/32/kup.h +++ b/arch/powerpc/include/asm/book3s/32/kup.h @@ -77,10 +77,6 @@ static inline void kuap_unlock(unsigned long addr, bool ool) kuap_unlock_all_ool(); } -static inline void __kuap_lock(void) -{ -} - static inline void __kuap_save_and_lock(struct pt_regs *regs) { unsigned long kuap = current->thread.kuap; @@ -92,6 +88,7 @@ static inline void __kuap_save_and_lock(struct pt_regs *regs) current->thread.kuap = KUAP_NONE; kuap_lock_addr(kuap, false); } +#define __kuap_save_and_lock __kuap_save_and_lock static inline void kuap_user_restore(struct pt_regs *regs) { @@ -120,6 +117,7 @@ static inline unsigned long __kuap_get_and_assert_locked(void) return kuap; } +#define __kuap_get_and_assert_locked __kuap_get_and_assert_locked static __always_inline void __allow_user_access(void __user *to, const void __user *from, u32 size, unsigned long dir) -- cgit