Commit 48cf12d8 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

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: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210320122227.345427-1-mpe@ellerman.id.au
parent d2313da4

arch/powerpc/include/asm/irq.h

+0 −2
Original line number Diff line number Diff line
@@ -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);

arch/powerpc/kernel/irq.c

+41 −0
Original line number Diff line number Diff line
@@ -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;

arch/powerpc/kernel/misc_32.S

+0 −25
Original line number Diff line number Diff line
@@ -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.

 */

arch/powerpc/kernel/misc_64.S

+0 −22
Original line number Diff line number Diff line
@@ -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