diff options
| author | Lu Baolu <baolu.lu@linux.intel.com> | 2022-07-12 03:08:55 +0300 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2022-07-15 11:21:35 +0300 |
| commit | 2e1c8dafb8c2c459baa5aef5b338c15edd9b9b5b (patch) | |
| tree | 946fe8d79d344ae29e9f30d64d2a27223e025e41 /drivers/iommu | |
| parent | 8ac0b64b9735ae896d200dd952c22999742b4414 (diff) | |
| download | linux-2e1c8dafb8c2c459baa5aef5b338c15edd9b9b5b.tar.xz | |
iommu/vt-d: Unnecessary spinlock for root table alloc and free
The IOMMU root table is allocated and freed in the IOMMU initialization
code in static boot or hot-remove paths. There's no need for a spinlock.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220706025524.2904370-5-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/intel/iommu.c | 18 |
1 files changed, 5 insertions, 13 deletions
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 77915d61f7ec..ff49c9460ede 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -809,14 +809,12 @@ static int device_context_mapped(struct intel_iommu *iommu, u8 bus, u8 devfn) static void free_context_table(struct intel_iommu *iommu) { - int i; - unsigned long flags; struct context_entry *context; + int i; + + if (!iommu->root_entry) + return; - spin_lock_irqsave(&iommu->lock, flags); - if (!iommu->root_entry) { - goto out; - } for (i = 0; i < ROOT_ENTRY_NR; i++) { context = iommu_context_addr(iommu, i, 0, 0); if (context) @@ -828,12 +826,10 @@ static void free_context_table(struct intel_iommu *iommu) context = iommu_context_addr(iommu, i, 0x80, 0); if (context) free_pgtable_page(context); - } + free_pgtable_page(iommu->root_entry); iommu->root_entry = NULL; -out: - spin_unlock_irqrestore(&iommu->lock, flags); } #ifdef CONFIG_DMAR_DEBUG @@ -1232,7 +1228,6 @@ static void domain_unmap(struct dmar_domain *domain, unsigned long start_pfn, static int iommu_alloc_root_entry(struct intel_iommu *iommu) { struct root_entry *root; - unsigned long flags; root = (struct root_entry *)alloc_pgtable_page(iommu->node); if (!root) { @@ -1242,10 +1237,7 @@ static int iommu_alloc_root_entry(struct intel_iommu *iommu) } __iommu_flush_cache(iommu, root, ROOT_SIZE); - - spin_lock_irqsave(&iommu->lock, flags); iommu->root_entry = root; - spin_unlock_irqrestore(&iommu->lock, flags); return 0; } |