Re: [Nouveau] [PATCH 21/22] mm: remove the HMM config option

2019-06-13 Thread Jason Gunthorpe
On Thu, Jun 13, 2019 at 11:43:24AM +0200, Christoph Hellwig wrote:
> All the mm/hmm.c code is better keyed off HMM_MIRROR.  Also let nouveau
> depend on it instead of the mix of a dummy dependency symbol plus the
> actually selected one.  Drop various odd dependencies, as the code is
> pretty portable.

I don't really know, but I thought this needed the arch restriction
for the same reason get_user_pages has various unique arch specific
implementations (it does seem to have some open coded GUP like thing)?

I was hoping we could do this after your common gup series? But sooner
is better too.

Jason
___
Nouveau mailing list
Nouveau@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/nouveau

[Nouveau] [PATCH 21/22] mm: remove the HMM config option

2019-06-13 Thread Christoph Hellwig
All the mm/hmm.c code is better keyed off HMM_MIRROR.  Also let nouveau
depend on it instead of the mix of a dummy dependency symbol plus the
actually selected one.  Drop various odd dependencies, as the code is
pretty portable.

Signed-off-by: Christoph Hellwig 
---
 drivers/gpu/drm/nouveau/Kconfig |  3 +--
 include/linux/hmm.h | 14 +++---
 include/linux/mm_types.h|  2 +-
 mm/Kconfig  | 27 +++
 mm/Makefile |  2 +-
 mm/hmm.c|  2 --
 6 files changed, 9 insertions(+), 41 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig
index 6303d203ab1d..66c839d8e9d1 100644
--- a/drivers/gpu/drm/nouveau/Kconfig
+++ b/drivers/gpu/drm/nouveau/Kconfig
@@ -84,11 +84,10 @@ config DRM_NOUVEAU_BACKLIGHT
 
 config DRM_NOUVEAU_SVM
bool "(EXPERIMENTAL) Enable SVM (Shared Virtual Memory) support"
-   depends on ARCH_HAS_HMM
depends on DEVICE_PRIVATE
depends on DRM_NOUVEAU
+   depends on HMM_MIRROR
depends on STAGING
-   select HMM_MIRROR
default n
help
  Say Y here if you want to enable experimental support for
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index e095a8b55dfa..64ea2fa00872 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -62,7 +62,7 @@
 #include 
 #include 
 
-#if IS_ENABLED(CONFIG_HMM)
+#ifdef CONFIG_HMM_MIRROR
 
 #include 
 #include 
@@ -324,9 +324,6 @@ static inline uint64_t hmm_pfn_from_pfn(const struct 
hmm_range *range,
return hmm_device_entry_from_pfn(range, pfn);
 }
 
-
-
-#if IS_ENABLED(CONFIG_HMM_MIRROR)
 /*
  * Mirroring: how to synchronize device page table with CPU page table.
  *
@@ -546,13 +543,8 @@ static inline void hmm_mm_init(struct mm_struct *mm)
 {
mm->hmm = NULL;
 }
-#else /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-static inline void hmm_mm_init(struct mm_struct *mm) {}
-#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-
-#else /* IS_ENABLED(CONFIG_HMM) */
-static inline void hmm_mm_destroy(struct mm_struct *mm) {}
+#else /* CONFIG_HMM_MIRROR */
 static inline void hmm_mm_init(struct mm_struct *mm) {}
-#endif /* IS_ENABLED(CONFIG_HMM) */
+#endif /* CONFIG_HMM_MIRROR */
 
 #endif /* LINUX_HMM_H */
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index f33a1289c101..8d37182f8dbe 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -501,7 +501,7 @@ struct mm_struct {
 #endif
struct work_struct async_put_work;
 
-#if IS_ENABLED(CONFIG_HMM)
+#ifdef CONFIG_HMM_MIRROR
/* HMM needs to track a few things per mm */
struct hmm *hmm;
 #endif
diff --git a/mm/Kconfig b/mm/Kconfig
index 4dbd718c8cf4..73676cb4693f 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -669,37 +669,17 @@ config ZONE_DEVICE
 
  If FS_DAX is enabled, then say Y.
 
-config ARCH_HAS_HMM_MIRROR
-   bool
-   default y
-   depends on (X86_64 || PPC64)
-   depends on MMU && 64BIT
-
-config ARCH_HAS_HMM
-   bool
-   depends on (X86_64 || PPC64)
-   depends on ZONE_DEVICE
-   depends on MMU && 64BIT
-   depends on MEMORY_HOTPLUG
-   depends on MEMORY_HOTREMOVE
-   depends on SPARSEMEM_VMEMMAP
-   default y
-
 config MIGRATE_VMA_HELPER
bool
 
 config DEV_PAGEMAP_OPS
bool
 
-config HMM
-   bool
-   select MMU_NOTIFIER
-   select MIGRATE_VMA_HELPER
-
 config HMM_MIRROR
bool "HMM mirror CPU page table into a device page table"
-   depends on ARCH_HAS_HMM
-   select HMM
+   depends on MMU
+   select MMU_NOTIFIER
+   select MIGRATE_VMA_HELPER
help
  Select HMM_MIRROR if you want to mirror range of the CPU page table 
of a
  process into a device page table. Here, mirror means "keep 
synchronized".
@@ -721,7 +701,6 @@ config DEVICE_PUBLIC
bool "Addressable device memory (like GPU memory)"
depends on ARCH_HAS_HMM
depends on BROKEN
-   select HMM
select DEV_PAGEMAP_OPS
 
help
diff --git a/mm/Makefile b/mm/Makefile
index ac5e5ba78874..91c99040065c 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -102,5 +102,5 @@ obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
 obj-$(CONFIG_DEBUG_PAGE_REF) += debug_page_ref.o
 obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o
 obj-$(CONFIG_PERCPU_STATS) += percpu-stats.o
-obj-$(CONFIG_HMM) += hmm.o
+obj-$(CONFIG_HMM_MIRROR) += hmm.o
 obj-$(CONFIG_MEMFD_CREATE) += memfd.o
diff --git a/mm/hmm.c b/mm/hmm.c
index 5b2e9bb6063a..8d50c482469c 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -26,7 +26,6 @@
 #include 
 #include 
 
-#if IS_ENABLED(CONFIG_HMM_MIRROR)
 static const struct mmu_notifier_ops hmm_mmu_notifier_ops;
 
 /**
@@ -1289,4 +1288,3 @@ long hmm_range_dma_unmap(struct hmm_range *range,
return cpages;
 }
 EXPORT_SYMBOL(hmm_range_dma_unmap);
-#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-- 
2.20.1