[hmm,0/6] Small hmm_range_fault() cleanups

Commit Message

Jason Gunthorpe March 20, 2020, 4:48 p.m. UTC

From: Jason Gunthorpe <[e-mail]>

I've had these in my work queue for a bit, nothing profound here, just some
small edits for clarity.

Ralph's hmm tester will need a small diff to work after this - which
illustrates how setting default_flags == 0 is the same as what was called
SNAPSHOT:


Jason Gunthorpe (6):
  mm/hmm: remove pgmap checking for devmap pages
  mm/hmm: return the fault type from hmm_pte_need_fault()
  mm/hmm: remove unused code and tidy comments
  mm/hmm: remove HMM_FAULT_SNAPSHOT
  mm/hmm: remove the CONFIG_TRANSPARENT_HUGEPAGE #ifdef
  mm/hmm: use device_private_entry_to_pfn()

 Documentation/vm/hmm.rst                |  12 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c |   2 +-
 drivers/gpu/drm/nouveau/nouveau_svm.c   |   2 +-
 include/linux/hmm.h                     |  55 +-----
 mm/hmm.c                                | 238 +++++++++---------------
 5 files changed, 98 insertions(+), 211 deletions(-)

Comments

Jason Gunthorpe March 20, 2020, 6:55 p.m. UTC | #1

On Fri, Mar 20, 2020 at 11:51:47AM -0700, Ralph Campbell wrote:
> 
> On 3/20/20 9:48 AM, Jason Gunthorpe wrote:
> > From: Jason Gunthorpe <[e-mail]>
> > 
> > I've had these in my work queue for a bit, nothing profound here, just some
> > small edits for clarity.
> 
> The hmm tester changes are clear enough but I'm having a bit of trouble figuring out
> what this series applies cleanly to since I'm trying to apply it on top of the
> other patches you and Christoph have sent out.
> Is there a private git tree/branch where everything is applied?

I accumulate everything here:

https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/log/?h=hmm

The patches should apply on top of that

Jason

Patch

diff --git a/lib/test_hmm.c b/lib/test_hmm.c
index 6ca953926dc13f..5f31f5b3e64cb9 100644
--- a/lib/test_hmm.c
+++ b/lib/test_hmm.c
@@ -300,7 +300,7 @@  static int dmirror_range_fault(struct dmirror *dmirror,
 
 		range->notifier_seq = mmu_interval_read_begin(range->notifier);
 		down_read(&mm->mmap_sem);
-		count = hmm_range_fault(range, 0);
+		count = hmm_range_fault(range);
 		up_read(&mm->mmap_sem);
 		if (count <= 0) {
 			if (count == 0 || count == -EBUSY)
@@ -337,8 +337,7 @@  static int dmirror_fault(struct dmirror *dmirror, unsigned long start,
 		.flags = dmirror_hmm_flags,
 		.values = dmirror_hmm_values,
 		.pfn_shift = DPT_SHIFT,
-		.pfn_flags_mask = ~(dmirror_hmm_flags[HMM_PFN_VALID] |
-				    dmirror_hmm_flags[HMM_PFN_WRITE]),
+		.pfn_flags_mask = 0,
 		.default_flags = dmirror_hmm_flags[HMM_PFN_VALID] |
 				(write ? dmirror_hmm_flags[HMM_PFN_WRITE] : 0),
 		.dev_private_owner = dmirror->mdevice,
@@ -872,7 +871,7 @@  static int dmirror_range_snapshot(struct dmirror *dmirror,
 		range->notifier_seq = mmu_interval_read_begin(range->notifier);
 
 		down_read(&mm->mmap_sem);
-		count = hmm_range_fault(range, HMM_FAULT_SNAPSHOT);
+		count = hmm_range_fault(range);
 		up_read(&mm->mmap_sem);
 		if (count <= 0) {
 			if (count == 0 || count == -EBUSY)
@@ -916,7 +915,7 @@  static int dmirror_snapshot(struct dmirror *dmirror,
 		.flags = dmirror_hmm_flags,
 		.values = dmirror_hmm_values,
 		.pfn_shift = DPT_SHIFT,
-		.pfn_flags_mask = ~0ULL,
+		.pfn_flags_mask = 0,
 		.dev_private_owner = dmirror->mdevice,
 	};
 	int ret = 0;