Commit 91fc46ec authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

powerpc/64s: move ret_from_fork etc above __end_soft_masked 



Code which runs with interrupts enabled should be moved above
__end_soft_masked where possible, because maskable interrupts that hit
below that symbol will need to consult the soft mask table, which is an
extra cost.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210630074621.2109197-10-npiggin@gmail.com
parent c59458b0

arch/powerpc/kernel/interrupt_64.S

+26 −26
Original line number Diff line number Diff line
@@ -449,32 +449,6 @@ _ASM_NOKPROBE_SYMBOL(tabort_syscall) 
	b	.	/* prevent speculative execution */

#endif



#ifdef CONFIG_PPC_BOOK3S

_GLOBAL(ret_from_fork_scv)

	bl	schedule_tail

	REST_NVGPRS(r1)

	li	r3,0	/* fork() return value */

	b	.Lsyscall_vectored_common_exit

#endif



_GLOBAL(ret_from_fork)

	bl	schedule_tail

	REST_NVGPRS(r1)

	li	r3,0	/* fork() return value */

	b	.Lsyscall_exit



_GLOBAL(ret_from_kernel_thread)

	bl	schedule_tail

	REST_NVGPRS(r1)

	mtctr	r14

	mr	r3,r15

#ifdef PPC64_ELF_ABI_v2

	mr	r12,r14

#endif

	bctrl

	li	r3,0

	b	.Lsyscall_exit



	/*

	 * If MSR EE/RI was never enabled, IRQs not reconciled, NVGPRs not

	 * touched, no exit work created, then this can be used.
@@ -768,3 +742,29 @@ interrupt_return_macro hsrr 
__end_soft_masked:

DEFINE_FIXED_SYMBOL(__end_soft_masked)

#endif /* CONFIG_PPC_BOOK3S */



#ifdef CONFIG_PPC_BOOK3S

_GLOBAL(ret_from_fork_scv)

	bl	schedule_tail

	REST_NVGPRS(r1)

	li	r3,0	/* fork() return value */

	b	.Lsyscall_vectored_common_exit

#endif



_GLOBAL(ret_from_fork)

	bl	schedule_tail

	REST_NVGPRS(r1)

	li	r3,0	/* fork() return value */

	b	.Lsyscall_exit



_GLOBAL(ret_from_kernel_thread)

	bl	schedule_tail

	REST_NVGPRS(r1)

	mtctr	r14

	mr	r3,r15

#ifdef PPC64_ELF_ABI_v2

	mr	r12,r14

#endif

	bctrl

	li	r3,0

	b	.Lsyscall_exit