From: Sebastian Andrzej Siewior Date: Thu, 22 Mar 2018 15:22:36 +0000 (+0100) Subject: iommu/amd: Split irq_lookup_table out of the amd_iommu_devtable_lock X-Git-Tag: v4.17-rc1~45^2~7 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=ea6166f4b83e9cfba1c18f46a764d50045682fe5;p=linux.git iommu/amd: Split irq_lookup_table out of the amd_iommu_devtable_lock The function get_irq_table() reads/writes irq_lookup_table while holding the amd_iommu_devtable_lock. It also modifies amd_iommu_dev_table[].data[2]. set_dte_entry() is using amd_iommu_dev_table[].data[0|1] (under the domain->lock) so it should be okay. The access to the iommu is serialized with its own (iommu's) lock. So split out get_irq_table() out of amd_iommu_devtable_lock's lock. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Joerg Roedel --- diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index fcfdce70707d..a87d2fee68db 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -82,6 +82,7 @@ static DEFINE_RWLOCK(amd_iommu_devtable_lock); static DEFINE_SPINLOCK(pd_bitmap_lock); +static DEFINE_SPINLOCK(iommu_table_lock); /* List of all available dev_data structures */ static LLIST_HEAD(dev_data_list); @@ -3623,7 +3624,7 @@ static struct irq_remap_table *alloc_irq_table(u16 devid, bool ioapic) unsigned long flags; u16 alias; - write_lock_irqsave(&amd_iommu_devtable_lock, flags); + spin_lock_irqsave(&iommu_table_lock, flags); iommu = amd_iommu_rlookup_table[devid]; if (!iommu) @@ -3688,7 +3689,7 @@ static struct irq_remap_table *alloc_irq_table(u16 devid, bool ioapic) iommu_completion_wait(iommu); out_unlock: - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock_irqrestore(&iommu_table_lock, flags); return table; }