RESEND [PATCH] - SN: Add support for CPU disable

From: John Keller
Date: Wed Aug 01 2007 - 17:00:33 EST

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Add additional support for CPU disable on SN platforms.
Correctly setup the smp_affinity mask for I/O error IRQs.
Restrict the use of the feature to Altix 4000 and 450 systems
running with a CPU disable capable PROM, and do not allow disabling
of CPU 0.

Signed-off-by: John Keller <jpk@xxxxxxx>
---

Resend #1:
Code was incorrectly passing a logical, instead of physical,
cpuid to set_irq_affinity_info(). Also, some cleanup per
review comments.

arch/ia64/kernel/smpboot.c | 6 +++++
arch/ia64/sn/kernel/huberror.c | 14 +++++++++---
arch/ia64/sn/kernel/irq.c | 15 +++++++++++++
arch/ia64/sn/kernel/sn2/sn2_smp.c | 24 ++++++++++++++++++++++
arch/ia64/sn/pci/pcibr/pcibr_provider.c | 1
arch/ia64/sn/pci/tioca_provider.c | 2 +
arch/ia64/sn/pci/tioce_provider.c | 1
include/asm-ia64/sn/arch.h | 1
include/asm-ia64/sn/intr.h | 1
include/asm-ia64/sn/sn_feature_sets.h | 1
10 files changed, 62 insertions(+), 4 deletions(-)

Index: linux-2.6/arch/ia64/sn/kernel/huberror.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/kernel/huberror.c 2007-08-01 14:28:07.683651839 -0500
+++ linux-2.6/arch/ia64/sn/kernel/huberror.c 2007-08-01 14:29:20.400606100 -0500
@@ -185,11 +185,14 @@ void hubiio_crb_error_handler(struct hub
*/
void hub_error_init(struct hubdev_info *hubdev_info)
{
+
if (request_irq(SGI_II_ERROR, hub_eint_handler, IRQF_SHARED,
- "SN_hub_error", (void *)hubdev_info))
+ "SN_hub_error", (void *)hubdev_info)) {
printk("hub_error_init: Failed to request_irq for 0x%p\n",
hubdev_info);
- return;
+ return;
+ }
+ sn_set_err_irq_affinity(SGI_II_ERROR);
}

@@ -202,11 +205,14 @@ void hub_error_init(struct hubdev_info *
*/
void ice_error_init(struct hubdev_info *hubdev_info)
{
+
if (request_irq
(SGI_TIO_ERROR, (void *)hub_eint_handler, IRQF_SHARED, "SN_TIO_error",
- (void *)hubdev_info))
+ (void *)hubdev_info)) {
printk("ice_error_init: request_irq() error hubdev_info 0x%p\n",
hubdev_info);
- return;
+ return;
+ }
+ sn_set_err_irq_affinity(SGI_TIO_ERROR);
}

Index: linux-2.6/arch/ia64/sn/pci/pcibr/pcibr_provider.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/pci/pcibr/pcibr_provider.c 2007-08-01 14:28:07.683651839 -0500
+++ linux-2.6/arch/ia64/sn/pci/pcibr/pcibr_provider.c 2007-08-01 14:29:20.420608563 -0500
@@ -145,6 +145,7 @@ pcibr_bus_fixup(struct pcibus_bussoft *p
printk(KERN_WARNING
"pcibr cannot allocate interrupt for error handler\n");
}
+ sn_set_err_irq_affinity(SGI_PCIASIC_ERROR);

/*
* Update the Bridge with the "kernel" pagesize
Index: linux-2.6/arch/ia64/sn/pci/tioca_provider.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/pci/tioca_provider.c 2007-08-01 14:28:07.695653317 -0500
+++ linux-2.6/arch/ia64/sn/pci/tioca_provider.c 2007-08-01 14:29:20.432610041 -0500
@@ -654,6 +654,8 @@ tioca_bus_fixup(struct pcibus_bussoft *p
__FUNCTION__, SGI_TIOCA_ERROR,
(int)tioca_common->ca_common.bs_persist_busnum);

+ sn_set_err_irq_affinity(SGI_TIOCA_ERROR);
+
/* Setup locality information */
controller->node = tioca_kern->ca_closest_node;
return tioca_common;
Index: linux-2.6/arch/ia64/sn/pci/tioce_provider.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/pci/tioce_provider.c 2007-08-01 14:28:07.695653317 -0500
+++ linux-2.6/arch/ia64/sn/pci/tioce_provider.c 2007-08-01 14:29:20.444611519 -0500
@@ -1034,6 +1034,7 @@ tioce_bus_fixup(struct pcibus_bussoft *p
tioce_common->ce_pcibus.bs_persist_segment,
tioce_common->ce_pcibus.bs_persist_busnum);

+ sn_set_err_irq_affinity(SGI_PCIASIC_ERROR);
return tioce_common;
}

Index: linux-2.6/include/asm-ia64/sn/sn_feature_sets.h
===================================================================
--- linux-2.6.orig/include/asm-ia64/sn/sn_feature_sets.h 2007-08-01 14:28:07.695653317 -0500
+++ linux-2.6/include/asm-ia64/sn/sn_feature_sets.h 2007-08-01 14:29:20.456612997 -0500
@@ -31,6 +31,7 @@ extern int sn_prom_feature_available(int
#define PRF_PAL_CACHE_FLUSH_SAFE 0
#define PRF_DEVICE_FLUSH_LIST 1
#define PRF_HOTPLUG_SUPPORT 2
+#define PRF_CPU_DISABLE_SUPPORT 3

/* --------------------- OS Features -------------------------------*/

Index: linux-2.6/arch/ia64/kernel/smpboot.c
===================================================================
--- linux-2.6.orig/arch/ia64/kernel/smpboot.c 2007-08-01 14:28:07.695653317 -0500
+++ linux-2.6/arch/ia64/kernel/smpboot.c 2007-08-01 14:29:20.468614474 -0500
@@ -58,6 +58,7 @@
#include <asm/system.h>
#include <asm/tlbflush.h>
#include <asm/unistd.h>
+#include <asm/sn/arch.h>

#define SMP_DEBUG 0

@@ -730,6 +731,11 @@ int __cpu_disable(void)
return (-EBUSY);
}

+ if (ia64_platform_is("sn2")) {
+ if (!sn_cpu_disable_allowed(cpu))
+ return -EBUSY;
+ }
+
cpu_clear(cpu, cpu_online_map);

if (migrate_platform_irqs(cpu)) {
Index: linux-2.6/arch/ia64/sn/kernel/sn2/sn2_smp.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/kernel/sn2/sn2_smp.c 2007-08-01 14:28:07.683651839 -0500
+++ linux-2.6/arch/ia64/sn/kernel/sn2/sn2_smp.c 2007-08-01 14:29:20.488616937 -0500
@@ -40,6 +40,7 @@
#include <asm/sn/shub_mmr.h>
#include <asm/sn/nodepda.h>
#include <asm/sn/rw_mmr.h>
+#include <asm/sn/sn_feature_sets.h>

DEFINE_PER_CPU(struct ptc_stats, ptcstats);
DECLARE_PER_CPU(struct ptc_stats, ptcstats);
@@ -429,6 +430,29 @@ void sn2_send_IPI(int cpuid, int vector,
sn_send_IPI_phys(nasid, physid, vector, delivery_mode);
}

+#ifdef CONFIG_HOTPLUG_CPU
+/**
+ * sn_cpu_disable_allowed - Determine if a CPU can be disabled.
+ * @cpu - CPU that is requested to be disabled.
+ *
+ * CPU disable is only allowed on SHub2 systems running with a PROM
+ * that supports CPU disable. It is not permitted to disable the boot processor.
+ */
+bool sn_cpu_disable_allowed(int cpu)
+{
+ if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT)) {
+ if (cpu != 0)
+ return true;
+ else
+ printk("Disabling the boot processor is not allowed.\n");
+
+ } else
+ printk("CPU disable is not supported on this system.\n");
+
+ return false;
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
#ifdef CONFIG_PROC_FS

#define PTC_BASENAME "sgi_sn/ptc_statistics"
Index: linux-2.6/include/asm-ia64/sn/arch.h
===================================================================
--- linux-2.6.orig/include/asm-ia64/sn/arch.h 2007-08-01 14:28:07.695653317 -0500
+++ linux-2.6/include/asm-ia64/sn/arch.h 2007-08-01 14:29:20.504618908 -0500
@@ -81,5 +81,6 @@ extern u8 sn_sharing_domain_size;
extern u8 sn_region_size;

extern void sn_flush_all_caches(long addr, long bytes);
+extern bool sn_cpu_disable_allowed(int cpu);

#endif /* _ASM_IA64_SN_ARCH_H */
Index: linux-2.6/arch/ia64/sn/kernel/irq.c
===================================================================
--- linux-2.6.orig/arch/ia64/sn/kernel/irq.c 2007-07-31 09:09:55.414522005 -0500
+++ linux-2.6/arch/ia64/sn/kernel/irq.c 2007-08-01 14:29:20.520620878 -0500
@@ -19,6 +19,7 @@
#include <asm/sn/pcidev.h>
#include <asm/sn/shub_mmr.h>
#include <asm/sn/sn_sal.h>
+#include <asm/sn/sn_feature_sets.h>

static void force_interrupt(int irq);
static void register_intr_pda(struct sn_irq_info *sn_irq_info);
@@ -233,6 +234,20 @@ static void sn_set_affinity_irq(unsigned
(void)sn_retarget_vector(sn_irq_info, nasid, slice);
}

+#ifdef CONFIG_SMP
+void sn_set_err_irq_affinity(unsigned int irq)
+{
+ /*
+ * On systems which support CPU disabling (SHub2), all error interrupts
+ * are targetted at the boot CPU.
+ */
+ if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT))
+ set_irq_affinity_info(irq, cpu_physical_id(0), 0);
+}
+#else
+void sn_set_err_irq_affinity(unsigned int irq) { }
+#endif
+
static void
sn_mask_irq(unsigned int irq)
{
Index: linux-2.6/include/asm-ia64/sn/intr.h
===================================================================
--- linux-2.6.orig/include/asm-ia64/sn/intr.h 2007-07-31 09:09:59.667043574 -0500
+++ linux-2.6/include/asm-ia64/sn/intr.h 2007-08-01 14:29:20.540623341 -0500
@@ -60,6 +60,7 @@ extern u64 sn_intr_alloc(nasid_t, int,
int, nasid_t, int);
extern void sn_intr_free(nasid_t, int, struct sn_irq_info *);
extern struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *, nasid_t, int);
+extern void sn_set_err_irq_affinity(unsigned int);
extern struct list_head **sn_irq_lh;

#define CPU_VECTOR_TO_IRQ(cpuid,vector) (vector)
-
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Next message: Bartlomiej Zolnierkiewicz: "Re: [PATCH] fix runtogether printk's in cmd64x IDE driver"
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Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]