From: Vineet Gupta <Vineet.Gupta1@synopsys.com> To: <linux-arch@vger.kernel.org>, <linux-kernel@vger.kernel.org> Cc: <arnd@arndb.de>, <arc-linux-dev@synopsys.com>, Vineet Gupta <Vineet.Gupta1@synopsys.com> Subject: [PATCH 05/28] ARCv2: STAR 9000814690: Really Re-enable interrupts to avoid deadlocks Date: Tue, 9 Jun 2015 17:18:05 +0530 [thread overview] Message-ID: <1433850508-26317-6-git-send-email-vgupta@synopsys.com> (raw) In-Reply-To: <1433850508-26317-1-git-send-email-vgupta@synopsys.com> The issue was, on HS when interrupt is taken, IRQ_ACT is set and that is NOT cleared unless we do RTIE (or manually clear it). Linux interrupt handling has top and bottom halves. Latter lead to softirqs (which can reschedule) AND expect interrupts to be REALLY re-enabled which was NOT happening for us since we only SETI, dont clear IRQ_ACT So we can have a state when both cores have taken interrupt (IRQ_ACT set), get rescheduled, both send IPI and wait in CSD lock which will never be cleared as cores can't take the pending IPI IRQ due to existing IRQ_ACT set. So local_irq_enable() now drops the IRQ_ACT.act bit to re-enable IRQs. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> --- arch/arc/include/asm/irqflags-arcv2.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arc/include/asm/irqflags-arcv2.h b/arch/arc/include/asm/irqflags-arcv2.h index 1eb41b00aac5..ad481c24070d 100644 --- a/arch/arc/include/asm/irqflags-arcv2.h +++ b/arch/arc/include/asm/irqflags-arcv2.h @@ -64,6 +64,11 @@ static inline void arch_local_irq_restore(unsigned long flags) */ static inline void arch_local_irq_enable(void) { + unsigned int irqact = read_aux_reg(AUX_IRQ_ACT); + + if (irqact & 0xffff) + write_aux_reg(AUX_IRQ_ACT, irqact & ~0xffff); + __asm__ __volatile__(" seti \n" : : : "memory"); } -- 1.9.1
WARNING: multiple messages have this Message-ID (diff)
From: Vineet Gupta <Vineet.Gupta1@synopsys.com> To: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Cc: arnd@arndb.de, arc-linux-dev@synopsys.com, Vineet Gupta <Vineet.Gupta1@synopsys.com> Subject: [PATCH 05/28] ARCv2: STAR 9000814690: Really Re-enable interrupts to avoid deadlocks Date: Tue, 9 Jun 2015 17:18:05 +0530 [thread overview] Message-ID: <1433850508-26317-6-git-send-email-vgupta@synopsys.com> (raw) In-Reply-To: <1433850508-26317-1-git-send-email-vgupta@synopsys.com> The issue was, on HS when interrupt is taken, IRQ_ACT is set and that is NOT cleared unless we do RTIE (or manually clear it). Linux interrupt handling has top and bottom halves. Latter lead to softirqs (which can reschedule) AND expect interrupts to be REALLY re-enabled which was NOT happening for us since we only SETI, dont clear IRQ_ACT So we can have a state when both cores have taken interrupt (IRQ_ACT set), get rescheduled, both send IPI and wait in CSD lock which will never be cleared as cores can't take the pending IPI IRQ due to existing IRQ_ACT set. So local_irq_enable() now drops the IRQ_ACT.act bit to re-enable IRQs. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> --- arch/arc/include/asm/irqflags-arcv2.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arc/include/asm/irqflags-arcv2.h b/arch/arc/include/asm/irqflags-arcv2.h index 1eb41b00aac5..ad481c24070d 100644 --- a/arch/arc/include/asm/irqflags-arcv2.h +++ b/arch/arc/include/asm/irqflags-arcv2.h @@ -64,6 +64,11 @@ static inline void arch_local_irq_restore(unsigned long flags) */ static inline void arch_local_irq_enable(void) { + unsigned int irqact = read_aux_reg(AUX_IRQ_ACT); + + if (irqact & 0xffff) + write_aux_reg(AUX_IRQ_ACT, irqact & ~0xffff); + __asm__ __volatile__(" seti \n" : : : "memory"); } -- 1.9.1
next prev parent reply other threads:[~2015-06-09 11:52 UTC|newest] Thread overview: 109+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-06-09 11:48 [PATCH 00/28] ARCv2 port to Linux - (B) ISA / Core / platform support Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 01/28] ARCv2: [intc] HS38 core interrupt controller Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 02/28] ARCv2: Support for ARCv2 ISA and HS38x cores Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 03/28] ARCv2: STAR 9000793984: Handle return from intr to Delay Slot Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 04/28] ARCv2: STAR 9000808988: signals involving " Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta [this message] 2015-06-09 11:48 ` [PATCH 05/28] ARCv2: STAR 9000814690: Really Re-enable interrupts to avoid deadlocks Vineet Gupta 2015-06-09 11:48 ` [PATCH 06/28] ARCv2: MMUv4: TLB programming Model changes Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 07/28] ARCv2: MMUv4: cache programming model changes Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 08/28] ARCv2: MMUv4: support aliasing icache config Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 09/28] ARCv2: optimised string/mem lib routines Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 10/28] ARCv2: Adhere to Zero Delay loop restriction Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 11/28] ARCv2: extable: Enable sorting at build time Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-24 5:51 ` Vineet Gupta 2015-06-24 5:51 ` Vineet Gupta 2015-06-29 20:38 ` David Daney 2015-06-30 4:41 ` Vineet Gupta 2015-06-30 4:41 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 12/28] ARCv2: clocksource: Introduce 64bit local RTC counter Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 13/28] ARC: make plat_smp_ops weak to allow over-rides Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 14/28] ARCv2: SMP: ARConnect debug/robustness Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 15/28] ARCv2: SMP: clocksource: Enable Global Real Time counter Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 16/28] ARCv2: SMP: intc: IDU 2nd level intc for dynamic IRQ distribution Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 17/28] ARC: add compiler barrier to LLSC based cmpxchg Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 12:23 ` Peter Zijlstra 2015-06-09 11:48 ` [PATCH 18/28] ARC: add smp barriers around atomics per memory-barrriers.txt Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 12:30 ` Peter Zijlstra 2015-06-10 9:17 ` Vineet Gupta 2015-06-10 10:53 ` Peter Zijlstra 2015-06-11 13:03 ` Vineet Gupta 2015-06-12 12:15 ` [PATCH v2] ARC: add smp barriers around atomics per Documentation/atomic_ops.txt Vineet Gupta 2015-06-12 12:15 ` Vineet Gupta 2015-06-12 13:04 ` Peter Zijlstra 2015-06-12 13:16 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 19/28] arch: conditionally define smp_{mb,rmb,wmb} Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 12:32 ` Peter Zijlstra 2015-06-09 11:48 ` [PATCH 20/28] ARCv2: barriers Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 12:40 ` Peter Zijlstra 2015-06-10 9:34 ` Vineet Gupta 2015-06-10 10:58 ` Peter Zijlstra 2015-06-10 13:01 ` Will Deacon 2015-06-11 12:13 ` Vineet Gupta 2015-06-11 13:39 ` Will Deacon 2015-06-19 13:13 ` Vineet Gupta 2015-06-19 13:13 ` Vineet Gupta 2015-06-19 13:13 ` Vineet Gupta 2015-06-22 13:36 ` Will Deacon 2015-06-22 13:36 ` Will Deacon 2015-06-22 13:36 ` Will Deacon 2015-06-23 7:58 ` [PATCH v2 " Vineet Gupta 2015-06-23 7:58 ` Vineet Gupta 2015-06-23 8:49 ` Will Deacon 2015-06-23 9:03 ` Vineet Gupta 2015-06-23 9:26 ` Will Deacon 2015-06-23 9:52 ` [PATCH v3 22/28] " Vineet Gupta 2015-06-23 9:52 ` Vineet Gupta 2015-06-23 16:28 ` Will Deacon 2015-06-23 9:25 ` [PATCH v2 20/28] " Peter Zijlstra 2015-06-23 8:02 ` [PATCH " Vineet Gupta 2015-06-09 11:48 ` [PATCH 21/28] ARC: Reduce bitops lines of code using macros Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-12 12:20 ` [PATCH v2] " Vineet Gupta 2015-06-12 12:20 ` Vineet Gupta 2015-06-12 13:05 ` Peter Zijlstra 2015-06-09 11:48 ` [PATCH 22/28] ARCv2: STAR 9000837815 workaround hardware exclusive transactions livelock Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 12:35 ` Peter Zijlstra 2015-06-10 10:01 ` Vineet Gupta 2015-06-10 11:02 ` Peter Zijlstra 2015-06-19 9:55 ` [PATCH v2 " Vineet Gupta 2015-06-19 9:55 ` Vineet Gupta 2015-06-19 9:59 ` Will Deacon 2015-06-19 10:09 ` Vineet Gupta 2015-06-23 7:59 ` Vineet Gupta 2015-06-23 7:59 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 23/28] ARCv2: SLC: Handle explcit flush for DMA ops (w/o IO-coherency) Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 24/28] ARCv2: All bits in place, allow ARCv2 builds Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 25/28] ARCv2: [nsim*hs*] Support simulation platforms for HS38x cores Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 26/28] ARC: [axs101] Prepare for AXS103 Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 27/28] ARCv2: [axs103] Support ARC SDP FPGA platform for HS38x cores Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta 2015-06-09 11:48 ` [PATCH 28/28] ARCv2: [vdk] dts files and defconfig for HS38 VDK Vineet Gupta 2015-06-09 11:48 ` Vineet Gupta
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