Commit 19926630 authored by David S. Miller's avatar David S. Miller
Browse files

sparc64: Call xcall_deliver() directly in some cases. 



For these cases the callers make sure:

1) The cpus indicated are online.

2) The current cpu is not in the list of indicated cpus.

Therefore we can pass a pointer to the mask directly.

One of the motivations in this transformation is to make use of
"&cpumask_of_cpu(cpu)" which evaluates to a pointer to constant
data in the kernel and thus takes up no stack space.

Hopefully someone in the future will change the interface of
arch_send_call_function_ipi() such that it passes a const cpumask_t
pointer so that this will optimize ever further.

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cd5bc89d

arch/sparc64/kernel/smp.c

+10 −23
Original line number Diff line number Diff line
@@ -792,16 +792,15 @@ extern unsigned long xcall_call_function; 


void arch_send_call_function_ipi(cpumask_t mask)

{

	smp_cross_call_masked(&xcall_call_function, 0, 0, 0, mask);

	xcall_deliver((u64) &xcall_call_function, 0, 0, &mask);

}



extern unsigned long xcall_call_function_single;



void arch_send_call_function_single_ipi(int cpu)

{

	cpumask_t mask = cpumask_of_cpu(cpu);



	smp_cross_call_masked(&xcall_call_function_single, 0, 0, 0, mask);

	xcall_deliver((u64) &xcall_call_function_single, 0, 0,

		      &cpumask_of_cpu(cpu));

}



/* Send cross call to all processors except self. */
@@ -959,24 +958,6 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page) 
	put_cpu();

}



static void __smp_receive_signal_mask(cpumask_t mask)

{

	smp_cross_call_masked(&xcall_receive_signal, 0, 0, 0, mask);

}



void smp_receive_signal(int cpu)

{

	cpumask_t mask = cpumask_of_cpu(cpu);



	if (cpu_online(cpu))

		__smp_receive_signal_mask(mask);

}



void smp_receive_signal_client(int irq, struct pt_regs *regs)

{

	clear_softint(1 << irq);

}



void smp_new_mmu_context_version_client(int irq, struct pt_regs *regs)

{

	struct mm_struct *mm;
@@ -1374,7 +1355,13 @@ void __init smp_cpus_done(unsigned int max_cpus) 


void smp_send_reschedule(int cpu)

{

	smp_receive_signal(cpu);

	xcall_deliver((u64) &xcall_receive_signal, 0, 0,

		      &cpumask_of_cpu(cpu));

}



void smp_receive_signal_client(int irq, struct pt_regs *regs)

{

	clear_softint(1 << irq);

}



/* This is a nop because we capture all other cpus

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