From 48cf12d88969bd4238b8769767eb476970319d93 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 19 Mar 2021 06:34:43 +0000 Subject: powerpc/irq: Inline call_do_irq() and call_do_softirq() call_do_irq() and call_do_softirq() are simple enough to be worth inlining. Inlining them avoids an mflr/mtlr pair plus a save/reload on stack. This is inspired from S390 arch. Several other arches do more or less the same. The way sparc arch does seems odd thought. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210320122227.345427-1-mpe@ellerman.id.au --- arch/powerpc/include/asm/irq.h | 2 -- arch/powerpc/kernel/irq.c | 41 +++++++++++++++++++++++++++++++++++++++++ arch/powerpc/kernel/misc_32.S | 25 ------------------------- arch/powerpc/kernel/misc_64.S | 22 ---------------------- 4 files changed, 41 insertions(+), 49 deletions(-) diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h index f3f264e441a7..b2bd58830430 100644 --- a/arch/powerpc/include/asm/irq.h +++ b/arch/powerpc/include/asm/irq.h @@ -53,8 +53,6 @@ extern void *mcheckirq_ctx[NR_CPUS]; extern void *hardirq_ctx[NR_CPUS]; extern void *softirq_ctx[NR_CPUS]; -void call_do_softirq(void *sp); -void call_do_irq(struct pt_regs *regs, void *sp); extern void do_IRQ(struct pt_regs *regs); extern void __init init_IRQ(void); extern void __do_irq(struct pt_regs *regs); diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 5b72abbff96c..260effc0a435 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -667,6 +667,47 @@ static inline void check_stack_overflow(void) } } +static __always_inline void call_do_softirq(const void *sp) +{ + /* Temporarily switch r1 to sp, call __do_softirq() then restore r1. */ + asm volatile ( + PPC_STLU " %%r1, %[offset](%[sp]) ;" + "mr %%r1, %[sp] ;" + "bl %[callee] ;" + PPC_LL " %%r1, 0(%%r1) ;" + : // Outputs + : // Inputs + [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_OVERHEAD), + [callee] "i" (__do_softirq) + : // Clobbers + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", + "cr7", "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", + "r11", "r12" + ); +} + +static __always_inline void call_do_irq(struct pt_regs *regs, void *sp) +{ + register unsigned long r3 asm("r3") = (unsigned long)regs; + + /* Temporarily switch r1 to sp, call __do_irq() then restore r1. */ + asm volatile ( + PPC_STLU " %%r1, %[offset](%[sp]) ;" + "mr %%r1, %[sp] ;" + "bl %[callee] ;" + PPC_LL " %%r1, 0(%%r1) ;" + : // Outputs + "+r" (r3) + : // Inputs + [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_OVERHEAD), + [callee] "i" (__do_irq) + : // Clobbers + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", + "cr7", "r0", "r4", "r5", "r6", "r7", "r8", "r9", "r10", + "r11", "r12" + ); +} + void __do_irq(struct pt_regs *regs) { unsigned int irq; diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S index acc410043b96..6a076bef2932 100644 --- a/arch/powerpc/kernel/misc_32.S +++ b/arch/powerpc/kernel/misc_32.S @@ -27,31 +27,6 @@ .text -_GLOBAL(call_do_softirq) - mflr r0 - stw r0,4(r1) - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3) - mr r1,r3 - bl __do_softirq - lwz r1,0(r1) - lwz r0,4(r1) - mtlr r0 - blr - -/* - * void call_do_irq(struct pt_regs *regs, void *sp); - */ -_GLOBAL(call_do_irq) - mflr r0 - stw r0,4(r1) - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) - mr r1,r4 - bl __do_irq - lwz r1,0(r1) - lwz r0,4(r1) - mtlr r0 - blr - /* * This returns the high 64 bits of the product of two 64-bit numbers. */ diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 070465825c21..4b761a18a74d 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -27,28 +27,6 @@ .text -_GLOBAL(call_do_softirq) - mflr r0 - std r0,16(r1) - stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3) - mr r1,r3 - bl __do_softirq - ld r1,0(r1) - ld r0,16(r1) - mtlr r0 - blr - -_GLOBAL(call_do_irq) - mflr r0 - std r0,16(r1) - stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) - mr r1,r4 - bl __do_irq - ld r1,0(r1) - ld r0,16(r1) - mtlr r0 - blr - _GLOBAL(__bswapdi2) EXPORT_SYMBOL(__bswapdi2) srdi r8,r3,32 -- cgit