Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754683AbZLRCbK (ORCPT ); Thu, 17 Dec 2009 21:31:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751075AbZLRCbJ (ORCPT ); Thu, 17 Dec 2009 21:31:09 -0500 Received: from mga01.intel.com ([192.55.52.88]:55490 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750860AbZLRCbH (ORCPT ); Thu, 17 Dec 2009 21:31:07 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.47,416,1257148800"; d="scan'208";a="524255381" Subject: [patch] x86, irq: allow 0xff for /proc/irq/[n]/smp_affinity on a 8 cpu system From: Suresh Siddha Reply-To: Suresh Siddha To: Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner Cc: LKML , John Blackwood , Dimitri Sivanich Content-Type: text/plain Organization: Intel Corp Date: Thu, 17 Dec 2009 18:29:46 -0800 Message-Id: <1261103386.2535.409.camel@sbs-t61> Mime-Version: 1.0 X-Mailer: Evolution 2.26.3 (2.26.3-1.fc11) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9045 Lines: 257 John Blackwood reported: > on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded), > and 32 bit (x86) kernel, once you change the irq smp_affinity of an irq > to be less than all cpus in the system, you can never change really the > irq smp_affinity back to be all cpus in the system (0xff) again, > even though no error status is returned on the "/bin/echo ff > > /proc/irq/[n]/smp_affinity" operation. > > This is due to that fact that BAD_APICID has the same value as > all cpus (0xff) on 32bit kernels, and thus the value returned from > set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated > as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes > are made. set_desc_affinity() is already checking if the incoming cpu mask intersects with the cpu online mask or not. So there is no need for the apic op cpu_mask_to_apicid_and() to check again and return BAD_APICID. Remove the BAD_APICID return value from cpu_mask_to_apicid_and() and also fix set_desc_affinity() to return -1 instead of using BAD_APICID to represent error conditions (as cpu_mask_to_apicid_and() can return logical or physical apicid values and BAD_APICID is really to represent bad physical apic id). Reported-by: John Blackwood Root-caused-by: John Blackwood Signed-off-by: Suresh Siddha --- arch/x86/include/asm/hw_irq.h | 3 ++- arch/x86/kernel/apic/apic_flat_64.c | 5 +---- arch/x86/kernel/apic/bigsmp_32.c | 5 +---- arch/x86/kernel/apic/io_apic.c | 32 ++++++++++++++------------------ arch/x86/kernel/apic/x2apic_cluster.c | 5 +---- arch/x86/kernel/apic/x2apic_phys.c | 5 +---- arch/x86/kernel/apic/x2apic_uv_x.c | 5 +---- arch/x86/kernel/uv_irq.c | 3 +-- 8 files changed, 22 insertions(+), 41 deletions(-) diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h index 08c48a8..eeac829 100644 --- a/arch/x86/include/asm/hw_irq.h +++ b/arch/x86/include/asm/hw_irq.h @@ -103,7 +103,8 @@ extern int assign_irq_vector(int, struct irq_cfg *, const struct cpumask *); extern void send_cleanup_vector(struct irq_cfg *); struct irq_desc; -extern unsigned int set_desc_affinity(struct irq_desc *, const struct cpumask *); +extern unsigned int set_desc_affinity(struct irq_desc *, const struct cpumask *, + unsigned int *dest_id); extern int IO_APIC_get_PCI_irq_vector(int bus, int devfn, int pin, struct io_apic_irq_attr *irq_attr); extern void setup_ioapic_dest(void); diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c index d0c99ab..eacbd2b 100644 --- a/arch/x86/kernel/apic/apic_flat_64.c +++ b/arch/x86/kernel/apic/apic_flat_64.c @@ -306,10 +306,7 @@ physflat_cpu_mask_to_apicid_and(const struct cpumask *cpumask, if (cpumask_test_cpu(cpu, cpu_online_mask)) break; } - if (cpu < nr_cpu_ids) - return per_cpu(x86_cpu_to_apicid, cpu); - - return BAD_APICID; + return per_cpu(x86_cpu_to_apicid, cpu); } struct apic apic_physflat = { diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c index 38dcecf..cb804c5 100644 --- a/arch/x86/kernel/apic/bigsmp_32.c +++ b/arch/x86/kernel/apic/bigsmp_32.c @@ -131,10 +131,7 @@ static unsigned int bigsmp_cpu_mask_to_apicid_and(const struct cpumask *cpumask, if (cpumask_test_cpu(cpu, cpu_online_mask)) break; } - if (cpu < nr_cpu_ids) - return bigsmp_cpu_to_logical_apicid(cpu); - - return BAD_APICID; + return bigsmp_cpu_to_logical_apicid(cpu); } static int bigsmp_phys_pkg_id(int cpuid_apic, int index_msb) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 11a5851..de00c46 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2276,26 +2276,28 @@ static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq /* * Either sets desc->affinity to a valid value, and returns - * ->cpu_mask_to_apicid of that, or returns BAD_APICID and + * ->cpu_mask_to_apicid of that in dest_id, or returns -1 and * leaves desc->affinity untouched. */ unsigned int -set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask) +set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask, + unsigned int *dest_id) { struct irq_cfg *cfg; unsigned int irq; if (!cpumask_intersects(mask, cpu_online_mask)) - return BAD_APICID; + return -1; irq = desc->irq; cfg = desc->chip_data; if (assign_irq_vector(irq, cfg, mask)) - return BAD_APICID; + return -1; cpumask_copy(desc->affinity, mask); - return apic->cpu_mask_to_apicid_and(desc->affinity, cfg->domain); + *dest_id = apic->cpu_mask_to_apicid_and(desc->affinity, cfg->domain); + return 0; } static int @@ -2311,12 +2313,11 @@ set_ioapic_affinity_irq_desc(struct irq_desc *desc, const struct cpumask *mask) cfg = desc->chip_data; spin_lock_irqsave(&ioapic_lock, flags); - dest = set_desc_affinity(desc, mask); - if (dest != BAD_APICID) { + ret = set_desc_affinity(desc, mask, &dest); + if (!ret) { /* Only the high 8 bits are valid. */ dest = SET_APIC_LOGICAL_ID(dest); __target_IO_APIC_irq(irq, dest, cfg); - ret = 0; } spin_unlock_irqrestore(&ioapic_lock, flags); @@ -3351,8 +3352,7 @@ static int set_msi_irq_affinity(unsigned int irq, const struct cpumask *mask) struct msi_msg msg; unsigned int dest; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; cfg = desc->chip_data; @@ -3384,8 +3384,7 @@ ir_set_msi_irq_affinity(unsigned int irq, const struct cpumask *mask) if (get_irte(irq, &irte)) return -1; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; irte.vector = cfg->vector; @@ -3567,8 +3566,7 @@ static int dmar_msi_set_affinity(unsigned int irq, const struct cpumask *mask) struct msi_msg msg; unsigned int dest; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; cfg = desc->chip_data; @@ -3623,8 +3621,7 @@ static int hpet_msi_set_affinity(unsigned int irq, const struct cpumask *mask) struct msi_msg msg; unsigned int dest; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; cfg = desc->chip_data; @@ -3730,8 +3727,7 @@ static int set_ht_irq_affinity(unsigned int irq, const struct cpumask *mask) struct irq_cfg *cfg; unsigned int dest; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; cfg = desc->chip_data; diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c index a5371ec..cf69c59 100644 --- a/arch/x86/kernel/apic/x2apic_cluster.c +++ b/arch/x86/kernel/apic/x2apic_cluster.c @@ -148,10 +148,7 @@ x2apic_cpu_mask_to_apicid_and(const struct cpumask *cpumask, break; } - if (cpu < nr_cpu_ids) - return per_cpu(x86_cpu_to_logical_apicid, cpu); - - return BAD_APICID; + return per_cpu(x86_cpu_to_logical_apicid, cpu); } static unsigned int x2apic_cluster_phys_get_apic_id(unsigned long x) diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c index a8989aa..8972f38 100644 --- a/arch/x86/kernel/apic/x2apic_phys.c +++ b/arch/x86/kernel/apic/x2apic_phys.c @@ -146,10 +146,7 @@ x2apic_cpu_mask_to_apicid_and(const struct cpumask *cpumask, break; } - if (cpu < nr_cpu_ids) - return per_cpu(x86_cpu_to_apicid, cpu); - - return BAD_APICID; + return per_cpu(x86_cpu_to_apicid, cpu); } static unsigned int x2apic_phys_get_apic_id(unsigned long x) diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index b684bb3..d56b0ef 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -225,10 +225,7 @@ uv_cpu_mask_to_apicid_and(const struct cpumask *cpumask, if (cpumask_test_cpu(cpu, cpu_online_mask)) break; } - if (cpu < nr_cpu_ids) - return per_cpu(x86_cpu_to_apicid, cpu); - - return BAD_APICID; + return per_cpu(x86_cpu_to_apicid, cpu); } static unsigned int x2apic_get_apic_id(unsigned long x) diff --git a/arch/x86/kernel/uv_irq.c b/arch/x86/kernel/uv_irq.c index 61d805d..ece73d8 100644 --- a/arch/x86/kernel/uv_irq.c +++ b/arch/x86/kernel/uv_irq.c @@ -215,8 +215,7 @@ static int uv_set_irq_affinity(unsigned int irq, const struct cpumask *mask) unsigned long mmr_offset; unsigned mmr_pnode; - dest = set_desc_affinity(desc, mask); - if (dest == BAD_APICID) + if (set_desc_affinity(desc, mask, &dest)) return -1; mmr_value = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/