diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2021-06-18 01:51:03 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-06-25 00:06:55 +1000 |
| commit | 59dc5bfca0cb6a29db1a50847684eb5c19f8f400 (patch) | |
| tree | e59ddd65cf780da3df22074afee961dc8503cdc2 /arch/powerpc/include/asm/ptrace.h | |
| parent | 1df7d5e4baeac74d14c1bee18b2dff9302b3efbc (diff) | |
powerpc/64s: avoid reloading (H)SRR registers if they are still valid
When an interrupt is taken, the SRR registers are set to return to where
it left off. Unless they are modified in the meantime, or the return
address or MSR are modified, there is no need to reload these registers
when returning from interrupt.
Introduce per-CPU flags that track the validity of SRR and HSRR
registers. These are cleared when returning from interrupt, when
using the registers for something else (e.g., OPAL calls), when
adjusting the return address or MSR of a context, and when context
switching (which changes the return address and MSR).
This improves the performance of interrupt returns.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fold in fixup patch from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210617155116.2167984-5-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/include/asm/ptrace.h')
| -rw-r--r-- | arch/powerpc/include/asm/ptrace.h | 52 |
1 files changed, 42 insertions, 10 deletions
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h index e06d61b668d4..5d69dafd80ad 100644 --- a/arch/powerpc/include/asm/ptrace.h +++ b/arch/powerpc/include/asm/ptrace.h @@ -123,6 +123,47 @@ struct pt_regs #endif /* __powerpc64__ */ #ifndef __ASSEMBLY__ +#include <asm/paca.h> + +#ifdef CONFIG_SMP +extern unsigned long profile_pc(struct pt_regs *regs); +#else +#define profile_pc(regs) instruction_pointer(regs) +#endif + +long do_syscall_trace_enter(struct pt_regs *regs); +void do_syscall_trace_leave(struct pt_regs *regs); + +static inline void regs_set_return_ip(struct pt_regs *regs, unsigned long ip) +{ + regs->nip = ip; +#ifdef CONFIG_PPC_BOOK3S_64 + local_paca->hsrr_valid = 0; + local_paca->srr_valid = 0; +#endif +} + +static inline void regs_set_return_msr(struct pt_regs *regs, unsigned long msr) +{ + regs->msr = msr; +#ifdef CONFIG_PPC_BOOK3S_64 + local_paca->hsrr_valid = 0; + local_paca->srr_valid = 0; +#endif +} + +static inline void set_return_regs_changed(void) +{ +#ifdef CONFIG_PPC_BOOK3S_64 + local_paca->hsrr_valid = 0; + local_paca->srr_valid = 0; +#endif +} + +static inline void regs_add_return_ip(struct pt_regs *regs, long offset) +{ + regs_set_return_ip(regs, regs->nip + offset); +} static inline unsigned long instruction_pointer(struct pt_regs *regs) { @@ -132,7 +173,7 @@ static inline unsigned long instruction_pointer(struct pt_regs *regs) static inline void instruction_pointer_set(struct pt_regs *regs, unsigned long val) { - regs->nip = val; + regs_set_return_ip(regs, val); } static inline unsigned long user_stack_pointer(struct pt_regs *regs) @@ -145,15 +186,6 @@ static inline unsigned long frame_pointer(struct pt_regs *regs) return 0; } -#ifdef CONFIG_SMP -extern unsigned long profile_pc(struct pt_regs *regs); -#else -#define profile_pc(regs) instruction_pointer(regs) -#endif - -long do_syscall_trace_enter(struct pt_regs *regs); -void do_syscall_trace_leave(struct pt_regs *regs); - #ifdef __powerpc64__ #define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1) #else |