From mboxrd@z Thu Jan 1 00:00:00 1970 From: yangyingliang@huawei.com (Yang Yingliang) Date: Thu, 24 Sep 2015 17:32:12 +0800 Subject: [RFC PATCH v6 0/3] arm/arm64: fix a migrating irq bug when hotplug cpu Message-ID: <1443087135-17044-1-git-send-email-yangyingliang@huawei.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org ---- Changes in v6: - Don't touch the existing file kernel/irq/migration.c and add migrating interrupts code to a new file kernel/irq/cpuhotplug.c suggested by Thomas. - Change some comments in patch #2 and #3. Changes in v5: - remove the macro that guard move_irqs() - use name irq_migrate_all_off_this_cpu instead of move_irqs Changes in v4: - select GENERIC_IRQ_MIGRATION when config GENERIC_IRQ_MIGRATION is enabled - add move_irqs() into kerne/irq/migration.c for cpu hotplug - use move_irqs() to migrate interrupts on arm/arm64 when cpu is going to down - split bugfix patch into seperate patches for arm and arm64 Changes in v3: - introduce config GENERIC_IRQ_MIGRATION for compiling migration.c - rename migrate_irqs in arch/ia64/kernel/irq.c to avoid compiling error Changes in v2: - use the exiting helper to set IRQD_MOVE_PCNTXT flag - use for_each_active_irq() instead of for_each_irq_desc() - add some warn messages when affinity is null or do set affinity failed ---- Hi All, There is a bug: When cpu is disabled, all irqs will be migratged to another cpu. In some cases, a new affinity is different, it needed to be coppied to irq's affinity. But if the type of irq is LPI, it's affinity will not be coppied because of irq_set_affinity's return value. As Marc and Will suggested, I refactor the arm/arm64 migrating interrupts code and fix the migrating irq bug before cpu is offline. I'm trying let the core code do the migrating interrupts matter. Add the migrating code to a new file kernel/irq/cpuhotplug.c and make it depend on GENERIC_IRQ_MIGRATION. Fix the bug by using irq_do_set_affinity. And use the new code to migrate interrupts before cpu is offline on arm and arm64. Cc: Jiang Liu Cc: Thomas Gleixner Cc: Marc Zyngier Cc: Mark Rutland Cc: Will Deacon Cc: Russell King - ARM Linux Cc: Hanjun Guo Yang Yingliang (3): genirq: introduce CONFIG_GENERIC_IRQ_MIGRATION and kernel/irq/cpuhotplug.c arm64: fix a migrating irq bug when hotplug cpu arm: fix a migrating irq bug when hotplug cpu arch/arm/Kconfig | 1 + arch/arm/include/asm/irq.h | 1 - arch/arm/kernel/irq.c | 62 ---------------------------------------- arch/arm/kernel/smp.c | 2 +- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/irq.h | 1 - arch/arm64/kernel/irq.c | 62 ---------------------------------------- arch/arm64/kernel/smp.c | 2 +- include/linux/irq.h | 2 ++ kernel/irq/Kconfig | 4 +++ kernel/irq/Makefile | 1 + kernel/irq/cpuhotplug.c | 68 ++++++++++++++++++++++++++++++++++++++++++++ 12 files changed, 79 insertions(+), 128 deletions(-) create mode 100644 kernel/irq/cpuhotplug.c -- 2.5.0