The patch titled
Subject: mm/hmm: invalidate device page table at start of invalidation
has been added to the -mm tree. Its filename is
mm-hmm-invalidate-device-page-table-at-start-of-invalidation.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-hmm-invalidate-device-page-table-at-start-of-invalidation.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-hmm-invalidate-device-page-table-at-start-of-invalidation.patch
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------------------------------------------------------
From: Jérôme Glisse <jglisse@xxxxxxxxxx>
Subject: mm/hmm: invalidate device page table at start of invalidation
Invalidate device page table at start of invalidation and invalidate in
progress CPU page table snapshooting at both start and end of any
invalidation.
This is helpful when device need to dirty page because the device page
table report the page as dirty. Dirtying page must happen in the start
mmu notifier callback and not in the end one.
Link: http://lkml.kernel.org/r/20181019160442.18723-7-jglisse@xxxxxxxxxx
Signed-off-by: Jérôme Glisse <jglisse@xxxxxxxxxx>
Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hmm.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
--- a/mm/hmm.c~mm-hmm-invalidate-device-page-table-at-start-of-invalidation
+++ a/mm/hmm.c
@@ -43,7 +43,6 @@ static const struct mmu_notifier_ops hmm
*
* @mm: mm struct this HMM struct is bound to
* @lock: lock protecting ranges list
- * @sequence: we track updates to the CPU page table with a sequence number
* @ranges: list of range being snapshotted
* @mirrors: list of mirrors for this mm
* @mmu_notifier: mmu notifier to track updates to CPU page table
@@ -52,7 +51,6 @@ static const struct mmu_notifier_ops hmm
struct hmm {
struct mm_struct *mm;
spinlock_t lock;
- atomic_t sequence;
struct list_head ranges;
struct list_head mirrors;
struct mmu_notifier mmu_notifier;
@@ -85,7 +83,6 @@ static struct hmm *hmm_register(struct m
return NULL;
INIT_LIST_HEAD(&hmm->mirrors);
init_rwsem(&hmm->mirrors_sem);
- atomic_set(&hmm->sequence, 0);
hmm->mmu_notifier.ops = NULL;
INIT_LIST_HEAD(&hmm->ranges);
spin_lock_init(&hmm->lock);
@@ -126,7 +123,7 @@ void hmm_mm_destroy(struct mm_struct *mm
kfree(mm->hmm);
}
-static int hmm_invalidate_range(struct hmm *hmm,
+static int hmm_invalidate_range(struct hmm *hmm, bool device,
const struct hmm_update *update)
{
struct hmm_mirror *mirror;
@@ -147,6 +144,9 @@ static int hmm_invalidate_range(struct h
}
spin_unlock(&hmm->lock);
+ if (!device)
+ return 0;
+
down_read(&hmm->mirrors_sem);
list_for_each_entry(mirror, &hmm->mirrors, list) {
int ret;
@@ -189,18 +189,21 @@ static void hmm_release(struct mmu_notif
}
static int hmm_invalidate_range_start(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long start,
- unsigned long end,
- bool blockable)
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end,
+ bool blockable)
{
+ struct hmm_update update;
struct hmm *hmm = mm->hmm;
VM_BUG_ON(!hmm);
- atomic_inc(&hmm->sequence);
-
- return 0;
+ update.start = start;
+ update.end = end;
+ update.event = HMM_UPDATE_INVALIDATE;
+ update.blockable = blockable;
+ return hmm_invalidate_range(hmm, true, &update);
}
static void hmm_invalidate_range_end(struct mmu_notifier *mn,
@@ -217,7 +220,7 @@ static void hmm_invalidate_range_end(str
update.end = end;
update.event = HMM_UPDATE_INVALIDATE;
update.blockable = true;
- hmm_invalidate_range(hmm, &update);
+ hmm_invalidate_range(hmm, false, &update);
}
static const struct mmu_notifier_ops hmm_mmu_notifier_ops = {
_
Patches currently in -mm which might be from jglisse@xxxxxxxxxx are
mm-hmm-fix-utf8.patch
mm-hmm-properly-handle-migration-pmd-v3.patch
mm-hmm-use-a-structure-for-update-callback-parameters-v2.patch
mm-hmm-invalidate-device-page-table-at-start-of-invalidation.patch
