Re: [PATCH v2 5/8] iommu/arm-smmu-v3: Precompute the invalidation commands
From: Nicolin Chen <hidden>
Date: 2026-07-07 20:32:36
Also in:
linux-iommu, linux-patches
On Mon, Jul 06, 2026 at 01:26:42PM -0300, Jason Gunthorpe wrote:
quoted hunk ↗ jump to hunk
@@ -2471,10 +2451,13 @@ static bool arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu, if (num_tg == 1) { if (!ttl) ttl = 3; - arm_smmu_cmdq_batch_add_ril(smmu, cmds, cmd, tlbi->leaf_only, - cur_tg << tg_lg2, 0, 0, ttl, - tg_enc); - return true; + tlbi->range.data0 = 0; + tlbi->range.data1 = + FIELD_PREP(CMDQ_TLBI_1_LEAF, tlbi->leaf_only) | + FIELD_PREP(CMDQ_TLBI_1_TTL, ttl) | + FIELD_PREP(CMDQ_TLBI_1_TG, tg_enc) | + (cur_tg << tg_lg2); + return; }
[...]
+ tlbi->range.data0 = + FIELD_PREP(CMDQ_TLBI_0_NUM, + DIV_ROUND_UP_ULL(num_tg, 1ULL << scale) - 1) | + FIELD_PREP(CMDQ_TLBI_0_SCALE, scale); + tlbi->range.data1 = FIELD_PREP(CMDQ_TLBI_1_LEAF, tlbi->leaf_only) | + FIELD_PREP(CMDQ_TLBI_1_TTL, ttl) | + FIELD_PREP(CMDQ_TLBI_1_TG, tg_enc) | + (cur_tg << tg_lg2);
Could this be slightly cleaner:
unsigned int num = 0, scale = 0;
...
if (num_tg == 1) {
if (!ttl)
ttl = 3;
goto build;
}
scale = fls64((num_tg - 1) / 32);
num = DIV_ROUND_UP_ULL(num_tg, 1ULL << scale) - 1;
build:
tlbi->range.data0 = FIELD_PREP(CMDQ_TLBI_0_NUM, num) |
FIELD_PREP(CMDQ_TLBI_0_SCALE, scale);
tlbi->range.data1 = FIELD_PREP(CMDQ_TLBI_1_LEAF, tlbi->leaf_only) |
FIELD_PREP(CMDQ_TLBI_1_TTL, ttl) |
FIELD_PREP(CMDQ_TLBI_1_TG, tg_enc) |
(cur_tg << tg_lg2);
?
quoted hunk ↗ jump to hunk
@@ -2711,6 +2711,14 @@ void arm_smmu_domain_inv_range(struct arm_smmu_domain *smmu_domain, rcu_read_lock(); invs = rcu_dereference(smmu_domain->invs); + /* Only precaculate RIL if it will be used. */
precalculate
+ if (invs->has_range_inv) {
+ if (!tlbi.range.use_full_inv)
+ arm_smmu_tlbi_calc_range(&tlbi);
+ } else {
+ tlbi.range.use_full_inv = true;I am a bit unsure about this line since invs has no RIL entry. Is it set for a defensive reason? Nicolin