From e04763713286b1e00e1c2a33fe2741caf9470f2b Mon Sep 17 00:00:00 2001 From: Milton Miller Date: Tue, 10 May 2011 19:29:06 +0000 Subject: [PATCH] powerpc: Remove call sites of MSG_ALL_BUT_SELF 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/smp.h | 2 +- arch/powerpc/kernel/kgdb.c | 2 +- arch/powerpc/kernel/smp.c | 19 +++++++++++++------ arch/powerpc/xmon/xmon.c | 2 +- 4 files changed, 16 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index 50873493a97c..91472c56800f 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -35,7 +35,7 @@ extern void cpu_die(void); #ifdef CONFIG_SMP -extern void smp_send_debugger_break(int cpu); +extern void smp_send_debugger_break(void); extern void smp_message_recv(int); extern void start_secondary_resume(void); diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c index 42850ee00ada..bd9d35f59cf4 100644 --- a/arch/powerpc/kernel/kgdb.c +++ b/arch/powerpc/kernel/kgdb.c @@ -109,7 +109,7 @@ static int kgdb_call_nmi_hook(struct pt_regs *regs) #ifdef CONFIG_SMP void kgdb_roundup_cpus(unsigned long flags) { - smp_send_debugger_break(MSG_ALL_BUT_SELF); + smp_send_debugger_break(); } #endif diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 87517ab6d365..b74411446922 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -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 diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index 91309c5c00d7..42541bbcc7fa 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -437,7 +437,7 @@ static int xmon_core(struct pt_regs *regs, int fromipi) xmon_owner = cpu; mb(); if (ncpus > 1) { - smp_send_debugger_break(MSG_ALL_BUT_SELF); + smp_send_debugger_break(); /* wait for other cpus to come in */ for (timeout = 100000000; timeout != 0; --timeout) { if (cpumask_weight(&cpus_in_xmon) >= ncpus) -- 2.45.2