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powerpc: Remove call sites of MSG_ALL_BUT_SELF

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The only user of MSG_ALL_BUT_SELF in the whole kernel tree is powerpc,
and it only uses it to start the debugger. Both debuggers always call
smp_send_debugger_break with MSG_ALL_BUT_SELF, and only mpic can do
anything more optimal than a loop over all online cpus, but all message
passing implementations have to code for this special delivery target.

Convert smp_send_debugger_break to take void and loop calling the smp_ops
message_pass function for each of the other cpus in the online cpumask.

Use raw_smp_processor_id() because we are either entering the debugger
or trying to start kdump and the additional warning it not useful were
it to trigger.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Milton Miller
2011-05-10 19:29:06 +00:00
committed by Benjamin Herrenschmidt
parent 2a116f3dd0
commit e047637132
4 changed files with 16 additions and 9 deletions
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19
arch/powerpc/kernel/smp.c
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@@ -218,11 +218,18 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
}
#ifdef CONFIG_DEBUGGER
void smp_send_debugger_break(int cpu)
#if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
void smp_send_debugger_break(void)
{
if (likely(smp_ops))
smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
int cpu;
int me = raw_smp_processor_id();
if (unlikely(!smp_ops))
return;
for_each_online_cpu(cpu)
if (cpu != me)
smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
}
#endif
@@ -230,9 +237,9 @@ void smp_send_debugger_break(int cpu)
void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
{
crash_ipi_function_ptr = crash_ipi_callback;
if (crash_ipi_callback && smp_ops) {
if (crash_ipi_callback) {
mb();
smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
smp_send_debugger_break();
}
}
#endif