[PATCH 14/20] arm/bL_switcher: Convert to hotplug state machine
From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
Date: 2016-11-17 18:38:32
Also in:
lkml
Subsystem:
arm port, cpu hotplug, the rest · Maintainers:
Russell King, Thomas Gleixner, Peter Zijlstra, Linus Torvalds
Install the callbacks via the state machine. Cc: Russell King <linux@armlinux.org.uk> Cc: linux-arm-kernel at lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/arm/common/bL_switcher.c | 34 ++++++++++++++++++++-------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 21 insertions(+), 14 deletions(-)
diff --git a/arch/arm/common/bL_switcher.c b/arch/arm/common/bL_switcher.c
index 37dc0fe1093f..46730017b3c5 100644
--- a/arch/arm/common/bL_switcher.c
+++ b/arch/arm/common/bL_switcher.c@@ -757,19 +757,18 @@ EXPORT_SYMBOL_GPL(bL_switcher_put_enabled); * while the switcher is active. * We're just not ready to deal with that given the trickery involved. */ -static int bL_switcher_hotplug_callback(struct notifier_block *nfb, - unsigned long action, void *hcpu) +static int bL_switcher_cpu_pre(unsigned int cpu) { - if (bL_switcher_active) { - int pairing = bL_switcher_cpu_pairing[(unsigned long)hcpu]; - switch (action & 0xf) { - case CPU_UP_PREPARE: - case CPU_DOWN_PREPARE: - if (pairing == -1) - return NOTIFY_BAD; - } - } - return NOTIFY_DONE; + int pairing; + + if (!bL_switcher_active) + return 0; + + pairing = bL_switcher_cpu_pairing[cpu]; + + if (pairing == -1) + return -EINVAL; + return 0; } static bool no_bL_switcher;
@@ -782,8 +781,15 @@ static int __init bL_switcher_init(void) if (!mcpm_is_available()) return -ENODEV; - cpu_notifier(bL_switcher_hotplug_callback, 0); - + cpuhp_setup_state_nocalls(CPUHP_ARM_BL_PREPARE, "arm/bl:prepare", + bL_switcher_cpu_pre, NULL); + ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "arm/bl:predown", + NULL, bL_switcher_cpu_pre); + if (ret < 0) { + cpuhp_remove_state_nocalls(CPUHP_ARM_BL_PREPARE); + pr_err("bL_switcher: Failed to allocate a hotplug state\n"); + return ret; + } if (!no_bL_switcher) { ret = bL_switcher_enable(); if (ret)
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 69abf2c09f6c..4b99b79c16e5 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h@@ -64,6 +64,7 @@ enum cpuhp_state { CPUHP_X86_CPUID_PREPARE, CPUHP_X86_MSR_PREPARE, CPUHP_NET_IUCV_PREPARE, + CPUHP_ARM_BL_PREPARE, CPUHP_TIMERS_DEAD, CPUHP_NOTF_ERR_INJ_PREPARE, CPUHP_MIPS_SOC_PREPARE,
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2.10.2