lkml.org 
[lkml]   [2015]   [Dec]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[tip:x86/apic] x86/irq: Trivial cleanups for x86 vector allocation code
    Commit-ID:  27dd9e6098141a9ebaafe48d50277fcae6e09775
    Gitweb: http://git.kernel.org/tip/27dd9e6098141a9ebaafe48d50277fcae6e09775
    Author: Jiang Liu <jiang.liu@linux.intel.com>
    AuthorDate: Mon, 30 Nov 2015 16:09:30 +0800
    Committer: Thomas Gleixner <tglx@linutronix.de>
    CommitDate: Thu, 10 Dec 2015 19:39:57 +0100

    x86/irq: Trivial cleanups for x86 vector allocation code

    Trivial cleanups for x86 vector allocation code:
    1) reorganize apic_chip_data to optimize for size and cache efficiency
    2) avoid redundant calling of irq_to_desc()
    3) refine code comments

    Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
    Cc: Joe Lawrence <joe.lawrence@stratus.com>
    Link: http://lkml.kernel.org/r/1448870970-1461-5-git-send-email-jiang.liu@linux.intel.com
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    ---
    arch/x86/kernel/apic/vector.c | 54 ++++++++++++++++++-------------------------
    1 file changed, 23 insertions(+), 31 deletions(-)

    diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
    index b63d6f8..0183c44 100644
    --- a/arch/x86/kernel/apic/vector.c
    +++ b/arch/x86/kernel/apic/vector.c
    @@ -23,9 +23,9 @@

    struct apic_chip_data {
    struct irq_cfg cfg;
    + u8 move_in_progress : 1;
    cpumask_var_t domain;
    cpumask_var_t old_domain;
    - u8 move_in_progress : 1;
    };

    struct irq_domain *x86_vector_domain;
    @@ -38,7 +38,7 @@ static struct apic_chip_data *legacy_irq_data[NR_IRQS_LEGACY];

    void lock_vector_lock(void)
    {
    - /* Used to the online set of cpus does not change
    + /* Used to ensure that the online set of cpus does not change
    * during assign_irq_vector.
    */
    raw_spin_lock(&vector_lock);
    @@ -100,8 +100,7 @@ static void free_apic_chip_data(struct apic_chip_data *data)
    }
    }

    -static int __assign_irq_vector(int irq, struct apic_chip_data *d,
    - const struct cpumask *mask)
    +static int assign_irq_vector(struct irq_data *data, const struct cpumask *mask)
    {
    /*
    * NOTE! The local APIC isn't very good at handling
    @@ -116,11 +115,15 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d,
    */
    static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
    static int current_offset = VECTOR_OFFSET_START % 16;
    - int cpu, err;
    + int cpu, err = -EBUSY;
    + struct irq_desc *desc = irq_data_to_desc(data);
    + struct apic_chip_data *d = data->chip_data;
    unsigned int dest;
    + unsigned long flags;

    + raw_spin_lock_irqsave(&vector_lock, flags);
    if (cpumask_intersects(d->old_domain, cpu_online_mask))
    - return -EBUSY;
    + goto out;

    /* Only try and allocate irqs on cpus that are present */
    err = -ENOSPC;
    @@ -187,7 +190,7 @@ next:
    d->cfg.vector = vector;
    d->cfg.dest_apicid = dest;
    for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask)
    - per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq);
    + per_cpu(vector_irq, new_cpu)[vector] = desc;
    cpumask_copy(d->domain, vector_cpumask);
    err = 0;
    break;
    @@ -198,37 +201,27 @@ next:
    cpumask_and(d->old_domain, d->old_domain, cpu_online_mask);
    d->move_in_progress = !cpumask_empty(d->old_domain);
    }
    -
    - return err;
    -}
    -
    -static int assign_irq_vector(int irq, struct apic_chip_data *data,
    - const struct cpumask *mask)
    -{
    - int err;
    - unsigned long flags;
    -
    - raw_spin_lock_irqsave(&vector_lock, flags);
    - err = __assign_irq_vector(irq, data, mask);
    +out:
    raw_spin_unlock_irqrestore(&vector_lock, flags);
    +
    return err;
    }

    -static int assign_irq_vector_policy(int irq, int node,
    - struct apic_chip_data *data,
    +static int assign_irq_vector_policy(struct irq_data *data, int node,
    struct irq_alloc_info *info)
    {
    if (info && info->mask)
    - return assign_irq_vector(irq, data, info->mask);
    + return assign_irq_vector(data, info->mask);
    if (node != NUMA_NO_NODE &&
    - assign_irq_vector(irq, data, cpumask_of_node(node)) == 0)
    + assign_irq_vector(data, cpumask_of_node(node)) == 0)
    return 0;
    - return assign_irq_vector(irq, data, apic->target_cpus());
    + return assign_irq_vector(data, apic->target_cpus());
    }

    -static void clear_irq_vector(int irq, struct apic_chip_data *data)
    +static void clear_irq_vector(struct irq_data *irq_data)
    {
    - struct irq_desc *desc = irq_to_desc(irq);
    + struct irq_desc *desc = irq_data_to_desc(irq_data);
    + struct apic_chip_data *data = irq_data->chip_data;
    int cpu, vector = data->cfg.vector;

    BUG_ON(!vector);
    @@ -276,7 +269,7 @@ static void x86_vector_free_irqs(struct irq_domain *domain,
    irq_data = irq_domain_get_irq_data(x86_vector_domain, virq + i);
    if (irq_data && irq_data->chip_data) {
    raw_spin_lock_irqsave(&vector_lock, flags);
    - clear_irq_vector(virq + i, irq_data->chip_data);
    + clear_irq_vector(irq_data);
    free_apic_chip_data(irq_data->chip_data);
    irq_domain_reset_irq_data(irq_data);
    raw_spin_unlock_irqrestore(&vector_lock, flags);
    @@ -321,7 +314,7 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
    irq_data->chip = &lapic_controller;
    irq_data->chip_data = data;
    irq_data->hwirq = virq + i;
    - err = assign_irq_vector_policy(virq + i, node, data, info);
    + err = assign_irq_vector_policy(irq_data, node, info);
    if (err)
    goto error;
    }
    @@ -483,8 +476,7 @@ void apic_ack_edge(struct irq_data *data)
    static int apic_set_affinity(struct irq_data *irq_data,
    const struct cpumask *dest, bool force)
    {
    - struct apic_chip_data *data = irq_data->chip_data;
    - int err, irq = irq_data->irq;
    + int err;

    if (!config_enabled(CONFIG_SMP))
    return -EPERM;
    @@ -492,7 +484,7 @@ static int apic_set_affinity(struct irq_data *irq_data,
    if (!cpumask_intersects(dest, cpu_online_mask))
    return -EINVAL;

    - err = assign_irq_vector(irq, data, dest);
    + err = assign_irq_vector(irq_data, dest);

    return err ? err : IRQ_SET_MASK_OK;
    }

    \
     
     \ /
      Last update: 2015-12-10 20:01    [W:3.204 / U:0.516 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site