iommu/arm-smmu-v3: Defer TLB invalidation until ->iotlb_sync()

Update the iommu_iotlb_gather structure passed to ->tlb_add_page() and
use this information to defer all TLB invalidation until ->iotlb_sync().
This drastically reduces contention on the command queue, since we can
insert our commands in batches rather than one-by-one.

Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Will Deacon 2019-07-02 17:16:33 +01:00
parent 587e6c10a7
commit 2af2e72b18

View File

@ -309,6 +309,13 @@
#define CMDQ_PROD_OWNED_FLAG Q_OVERFLOW_FLAG
/*
* This is used to size the command queue and therefore must be at least
* BITS_PER_LONG so that the valid_map works correctly (it relies on the
* total number of queue entries being a multiple of BITS_PER_LONG).
*/
#define CMDQ_BATCH_ENTRIES BITS_PER_LONG
#define CMDQ_0_OP GENMASK_ULL(7, 0)
#define CMDQ_0_SSV (1UL << 11)
@ -1940,15 +1947,17 @@ static void arm_smmu_tlb_inv_context(void *cookie)
arm_smmu_cmdq_issue_sync(smmu);
}
static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
size_t granule, bool leaf, void *cookie)
static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
size_t granule, bool leaf,
struct arm_smmu_domain *smmu_domain)
{
struct arm_smmu_domain *smmu_domain = cookie;
u64 cmds[CMDQ_BATCH_ENTRIES * CMDQ_ENT_DWORDS];
struct arm_smmu_device *smmu = smmu_domain->smmu;
unsigned long end = iova + size;
int i = 0;
struct arm_smmu_cmdq_ent cmd = {
.tlbi = {
.leaf = leaf,
.addr = iova,
},
};
@ -1960,37 +1969,41 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
cmd.tlbi.vmid = smmu_domain->s2_cfg.vmid;
}
do {
arm_smmu_cmdq_issue_cmd(smmu, &cmd);
cmd.tlbi.addr += granule;
} while (size -= granule);
while (iova < end) {
if (i == CMDQ_BATCH_ENTRIES) {
arm_smmu_cmdq_issue_cmdlist(smmu, cmds, i, false);
i = 0;
}
cmd.tlbi.addr = iova;
arm_smmu_cmdq_build_cmd(&cmds[i * CMDQ_ENT_DWORDS], &cmd);
iova += granule;
i++;
}
arm_smmu_cmdq_issue_cmdlist(smmu, cmds, i, true);
}
static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
unsigned long iova, size_t granule,
void *cookie)
{
arm_smmu_tlb_inv_range_nosync(iova, granule, granule, true, cookie);
struct arm_smmu_domain *smmu_domain = cookie;
struct iommu_domain *domain = &smmu_domain->domain;
iommu_iotlb_gather_add_page(domain, gather, iova, granule);
}
static void arm_smmu_tlb_inv_walk(unsigned long iova, size_t size,
size_t granule, void *cookie)
{
struct arm_smmu_domain *smmu_domain = cookie;
struct arm_smmu_device *smmu = smmu_domain->smmu;
arm_smmu_tlb_inv_range_nosync(iova, size, granule, false, cookie);
arm_smmu_cmdq_issue_sync(smmu);
arm_smmu_tlb_inv_range(iova, size, granule, false, cookie);
}
static void arm_smmu_tlb_inv_leaf(unsigned long iova, size_t size,
size_t granule, void *cookie)
{
struct arm_smmu_domain *smmu_domain = cookie;
struct arm_smmu_device *smmu = smmu_domain->smmu;
arm_smmu_tlb_inv_range_nosync(iova, size, granule, true, cookie);
arm_smmu_cmdq_issue_sync(smmu);
arm_smmu_tlb_inv_range(iova, size, granule, true, cookie);
}
static const struct iommu_flush_ops arm_smmu_flush_ops = {
@ -2404,10 +2417,10 @@ static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
static void arm_smmu_iotlb_sync(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather)
{
struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu;
struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
if (smmu)
arm_smmu_cmdq_issue_sync(smmu);
arm_smmu_tlb_inv_range(gather->start, gather->end - gather->start,
gather->pgsize, true, smmu_domain);
}
static phys_addr_t
@ -3334,15 +3347,15 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
/* Queue sizes, capped to ensure natural alignment */
smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
FIELD_GET(IDR1_CMDQS, reg));
if (smmu->cmdq.q.llq.max_n_shift < ilog2(BITS_PER_LONG)) {
if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
/*
* The cmdq valid_map relies on the total number of entries
* being a multiple of BITS_PER_LONG. There's also no way
* we can handle the weird alignment restrictions on the
* base pointer for a unit-length queue.
* We don't support splitting up batches, so one batch of
* commands plus an extra sync needs to fit inside the command
* queue. There's also no way we can handle the weird alignment
* restrictions on the base pointer for a unit-length queue.
*/
dev_err(smmu->dev, "command queue size < %d entries not supported\n",
BITS_PER_LONG);
dev_err(smmu->dev, "command queue size <= %d entries not supported\n",
CMDQ_BATCH_ENTRIES);
return -ENXIO;
}