From 0a0a6800b02489c1288f963ad290b6a4876a2cc8 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 31 May 2023 15:08:41 +0200 Subject: [PATCH] x86,amd_iommu: Replace cmpxchg_double() Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Arnd Bergmann Reviewed-by: Mark Rutland Tested-by: Vasant Hegde Tested-by: Mark Rutland Link: https://lore.kernel.org/r/20230531132323.788955257@infradead.org --- drivers/iommu/amd/amd_iommu_types.h | 9 +++++++-- drivers/iommu/amd/iommu.c | 10 ++++------ 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h index 2ddbda3..ab8aa8f 100644 --- a/drivers/iommu/amd/amd_iommu_types.h +++ b/drivers/iommu/amd/amd_iommu_types.h @@ -986,8 +986,13 @@ union irte_ga_hi { }; struct irte_ga { - union irte_ga_lo lo; - union irte_ga_hi hi; + union { + struct { + union irte_ga_lo lo; + union irte_ga_hi hi; + }; + u128 irte; + }; }; struct irq_2_irte { diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 4a31464..1e9f85e 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -3003,10 +3003,10 @@ out: static int modify_irte_ga(struct amd_iommu *iommu, u16 devid, int index, struct irte_ga *irte, struct amd_ir_data *data) { - bool ret; struct irq_remap_table *table; - unsigned long flags; struct irte_ga *entry; + unsigned long flags; + u128 old; table = get_irq_table(iommu, devid); if (!table) @@ -3017,16 +3017,14 @@ static int modify_irte_ga(struct amd_iommu *iommu, u16 devid, int index, entry = (struct irte_ga *)table->table; entry = &entry[index]; - ret = cmpxchg_double(&entry->lo.val, &entry->hi.val, - entry->lo.val, entry->hi.val, - irte->lo.val, irte->hi.val); /* * We use cmpxchg16 to atomically update the 128-bit IRTE, * and it cannot be updated by the hardware or other processors * behind us, so the return value of cmpxchg16 should be the * same as the old value. */ - WARN_ON(!ret); + old = entry->irte; + WARN_ON(!try_cmpxchg128(&entry->irte, &old, irte->irte)); if (data) data->ref = entry; -- 2.7.4