In order to reduce CPU usage [1] and in theory TLB misses this patchset enables
huge- and giant page-table entries for TTM and TTM-enabled graphics drivers.
Patch 1 and 2 introduce a vma_is_special_huge() function to make the mm code
take the same path as DAX when splitting huge- and giant page table entries,
(which currently means zapping the page-table entry and rely on re-faulting).
Patch 3 makes the mm code split existing huge page-table entries
on huge_fault fallbacks. Typically on COW or on buffer-objects that want
write-notify. COW and write-notification is always done on the lowest
page-table level. See the patch log message for additional considerations.
Patch 4 introduces functions to allow the graphics drivers to manipulate
the caching- and encryption flags of huge page-table entries without ugly
hacks.
Patch 5 implements the huge_fault handler in TTM.
This enables huge page-table entries, provided that the kernel is configured
to support transhuge pages, either by default or using madvise().
However, they are unlikely to be inserted unless the kernel buffer object
pfns and user-space addresses align perfectly. There are various options
here, but since buffer objects that reside in system pages typically start
at huge page boundaries if they are backed by huge pages, we try to enforce
buffer object starting pfns and user-space addresses to be huge page-size
aligned if their size exceeds a huge page-size. If pud-size transhuge
("giant") pages are enabled by the arch, the same holds for those.
Patch 6 implements a specialized huge_fault handler for vmwgfx.
The vmwgfx driver may perform dirty-tracking and needs some special code
to handle that correctly.
Patch 7 implements a drm helper to align user-space addresses according
to the above scheme, if possible.
Patch 8 implements a TTM range manager for vmwgfx that does the same for
graphics IO memory. This may later be reused by other graphics drivers
if necessary.
Patch 9 finally hooks up the helpers of patch 7 and 8 to the vmwgfx driver.
A similar change is needed for graphics drivers that want a reasonable
likelyhood of actually using huge page-table entries.
If a buffer object size is not huge-page or giant-page aligned,
its size will NOT be inflated by this patchset. This means that the buffer
object tail will use smaller size page-table entries and thus no memory
overhead occurs. Drivers that want to pay the memory overhead price need to
implement their own scheme to inflate buffer-object sizes.
PMD size huge page-table-entries have been tested with vmwgfx and found to
work well both with system memory backed and IO memory backed buffer objects.
PUD size giant page-table-entries have seen limited (fault and COW) testing
using a modified kernel (to support 1GB page allocations) and a fake vmwgfx
TTM memory type. The vmwgfx driver does otherwise not support 1GB-size IO
memory resources.
Comments and suggestions welcome.
Thomas
Changes since RFC:
* Check for buffer objects present in contigous IO Memory (Christian König)
* Rebased on the vmwgfx emulated coherent memory functionality. That rebase
adds patch 5.
Changes since v1:
* Make the new TTM range manager vmwgfx-specific. (Christian König)
* Minor fixes for configs that don't support or only partially support
transhuge pages.
Changes since v2:
* Minor coding style and doc fixes in patch 5/9 (Christian König)
* Patch 5/9 doesn't touch mm. Remove from the patch title.
Changes since v3:
* Added reviews and acks
* Implemented ugly but generic ttm_pgprot_is_wrprotecting() instead of arch
specific code.
Changes since v4:
* Added timings (Andrew Morton)
* Updated function documentation (Andrew Morton)
Changes since v6:
* Fix drm build error with !CONFIG_MMU
[1]
The below test program generates the following gnu time output when run on a
vmwgfx-enabled kernel without the patch series:
4.78user 6.02system 0:10.91elapsed 99%CPU (0avgtext+0avgdata 1624maxresident)k
0inputs+0outputs (0major+640077minor)pagefaults 0swaps
and with the patch series:
1.71user 3.60system 0:05.40elapsed 98%CPU (0avgtext+0avgdata 1656maxresident)k
0inputs+0outputs (0major+20079minor)pagefaults 0swaps
A consistent number of reduced graphics page-faults can be seen with normal
graphics applications, but due to the aggressive buffer object caching in
vmwgfx user-space drivers the CPU time reduction is within the error marginal.
#include <unistd.h>
#include <string.h>
#include <sys/mman.h>
#include <xf86drm.h>
static void checkerr(int ret, const char *name)
{
if (ret < 0) {
perror(name);
exit(-1);
}
}
int main(int agc, const char *argv[])
{
struct drm_mode_create_dumb c_arg = {0};
struct drm_mode_map_dumb m_arg = {0};
struct drm_mode_destroy_dumb d_arg = {0};
int ret, i, fd;
void *map;
fd = open("/dev/dri/card0", O_RDWR);
checkerr(fd, argv[0]);
for (i = 0; i < 10000; ++i) {
c_arg.bpp = 32;
c_arg.width = 1024;
c_arg.height = 1024;
ret = drmIoctl(fd, DRM_IOCTL_MODE_CREATE_DUMB, &c_arg);
checkerr(fd, argv[0]);
m_arg.handle = c_arg.handle;
ret = drmIoctl(fd, DRM_IOCTL_MODE_MAP_DUMB, &m_arg);
checkerr(fd, argv[0]);
map = mmap(NULL, c_arg.size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
m_arg.offset);
checkerr(map == MAP_FAILED ? -1 : 0, argv[0]);
(void) madvise((void *) map, c_arg.size, MADV_HUGEPAGE);
memset(map, 0x67, c_arg.size);
munmap(map, c_arg.size);
d_arg.handle = c_arg.handle;
ret = drmIoctl(fd, DRM_IOCTL_MODE_DESTROY_DUMB, &d_arg);
checkerr(ret, argv[0]);
}
close(fd);
}
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
From: Thomas Hellstrom <[email protected]>
Unaligned virtual addresses makes it unlikely that huge page-table entries
can be used.
So align virtual buffer object address huge page boundaries to the
underlying physical address huge page boundaries taking buffer object
sizes into account to determine when it might be possible to use huge
page-table entries.
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Acked-by: Christian König <[email protected]>
---
drivers/gpu/drm/drm_file.c | 140 +++++++++++++++++++++++++++++++++++++
include/drm/drm_file.h | 9 +++
2 files changed, 149 insertions(+)
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index 92d16724f949..77e691202b52 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -48,6 +48,11 @@
#include "drm_internal.h"
#include "drm_legacy.h"
+#ifdef CONFIG_MMU
+#include <uapi/asm/mman.h>
+#include <drm/drm_vma_manager.h>
+#endif
+
/* from BKL pushdown */
DEFINE_MUTEX(drm_global_mutex);
@@ -796,3 +801,138 @@ struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
return file;
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
+
+#ifdef CONFIG_MMU
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+/*
+ * drm_addr_inflate() attempts to construct an aligned area by inflating
+ * the area size and skipping the unaligned start of the area.
+ * adapted from shmem_get_unmapped_area()
+ */
+static unsigned long drm_addr_inflate(unsigned long addr,
+ unsigned long len,
+ unsigned long pgoff,
+ unsigned long flags,
+ unsigned long huge_size)
+{
+ unsigned long offset, inflated_len;
+ unsigned long inflated_addr;
+ unsigned long inflated_offset;
+
+ offset = (pgoff << PAGE_SHIFT) & (huge_size - 1);
+ if (offset && offset + len < 2 * huge_size)
+ return addr;
+ if ((addr & (huge_size - 1)) == offset)
+ return addr;
+
+ inflated_len = len + huge_size - PAGE_SIZE;
+ if (inflated_len > TASK_SIZE)
+ return addr;
+ if (inflated_len < len)
+ return addr;
+
+ inflated_addr = current->mm->get_unmapped_area(NULL, 0, inflated_len,
+ 0, flags);
+ if (IS_ERR_VALUE(inflated_addr))
+ return addr;
+ if (inflated_addr & ~PAGE_MASK)
+ return addr;
+
+ inflated_offset = inflated_addr & (huge_size - 1);
+ inflated_addr += offset - inflated_offset;
+ if (inflated_offset > offset)
+ inflated_addr += huge_size;
+
+ if (inflated_addr > TASK_SIZE - len)
+ return addr;
+
+ return inflated_addr;
+}
+
+/**
+ * drm_get_unmapped_area() - Get an unused user-space virtual memory area
+ * suitable for huge page table entries.
+ * @file: The struct file representing the address space being mmap()'d.
+ * @uaddr: Start address suggested by user-space.
+ * @len: Length of the area.
+ * @pgoff: The page offset into the address space.
+ * @flags: mmap flags
+ * @mgr: The address space manager used by the drm driver. This argument can
+ * probably be removed at some point when all drivers use the same
+ * address space manager.
+ *
+ * This function attempts to find an unused user-space virtual memory area
+ * that can accommodate the size we want to map, and that is properly
+ * aligned to facilitate huge page table entries matching actual
+ * huge pages or huge page aligned memory in buffer objects. Buffer objects
+ * are assumed to start at huge page boundary pfns (io memory) or be
+ * populated by huge pages aligned to the start of the buffer object
+ * (system- or coherent memory). Adapted from shmem_get_unmapped_area.
+ *
+ * Return: aligned user-space address.
+ */
+unsigned long drm_get_unmapped_area(struct file *file,
+ unsigned long uaddr, unsigned long len,
+ unsigned long pgoff, unsigned long flags,
+ struct drm_vma_offset_manager *mgr)
+{
+ unsigned long addr;
+ unsigned long inflated_addr;
+ struct drm_vma_offset_node *node;
+
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ /*
+ * @pgoff is the file page-offset the huge page boundaries of
+ * which typically aligns to physical address huge page boundaries.
+ * That's not true for DRM, however, where physical address huge
+ * page boundaries instead are aligned with the offset from
+ * buffer object start. So adjust @pgoff to be the offset from
+ * buffer object start.
+ */
+ drm_vma_offset_lock_lookup(mgr);
+ node = drm_vma_offset_lookup_locked(mgr, pgoff, 1);
+ if (node)
+ pgoff -= node->vm_node.start;
+ drm_vma_offset_unlock_lookup(mgr);
+
+ addr = current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
+ if (IS_ERR_VALUE(addr))
+ return addr;
+ if (addr & ~PAGE_MASK)
+ return addr;
+ if (addr > TASK_SIZE - len)
+ return addr;
+
+ if (len < HPAGE_PMD_SIZE)
+ return addr;
+ if (flags & MAP_FIXED)
+ return addr;
+ /*
+ * Our priority is to support MAP_SHARED mapped hugely;
+ * and support MAP_PRIVATE mapped hugely too, until it is COWed.
+ * But if caller specified an address hint, respect that as before.
+ */
+ if (uaddr)
+ return addr;
+
+ inflated_addr = drm_addr_inflate(addr, len, pgoff, flags,
+ HPAGE_PMD_SIZE);
+
+ if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
+ len >= HPAGE_PUD_SIZE)
+ inflated_addr = drm_addr_inflate(inflated_addr, len, pgoff,
+ flags, HPAGE_PUD_SIZE);
+ return inflated_addr;
+}
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+unsigned long drm_get_unmapped_area(struct file *file,
+ unsigned long uaddr, unsigned long len,
+ unsigned long pgoff, unsigned long flags,
+ struct drm_vma_offset_manager *mgr)
+{
+ return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#endif /* CONFIG_MMU */
diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
index 8b099b347817..fd88fcb380d2 100644
--- a/include/drm/drm_file.h
+++ b/include/drm/drm_file.h
@@ -390,4 +390,13 @@ void drm_send_event(struct drm_device *dev, struct drm_pending_event *e);
struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags);
+#ifdef CONFIG_MMU
+struct drm_vma_offset_manager;
+unsigned long drm_get_unmapped_area(struct file *file,
+ unsigned long uaddr, unsigned long len,
+ unsigned long pgoff, unsigned long flags,
+ struct drm_vma_offset_manager *mgr);
+#endif /* CONFIG_MMU */
+
+
#endif /* _DRM_FILE_H_ */
--
2.21.1
From: Thomas Hellstrom <[email protected]>
For VM_PFNMAP and VM_MIXEDMAP vmas that want to support transhuge pages
and -page table entries, introduce vma_is_special_huge() that takes the
same codepaths as vma_is_dax().
The use of "special" follows the definition in memory.c, vm_normal_page():
"Special" mappings do not wish to be associated with a "struct page"
(either it doesn't exist, or it exists but they don't want to touch it)
For PAGE_SIZE pages, "special" is determined per page table entry to be
able to deal with COW pages. But since we don't have huge COW pages,
we can classify a vma as either "special huge" or "normal huge".
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Acked-by: Christian König <[email protected]>
---
include/linux/mm.h | 17 +++++++++++++++++
mm/huge_memory.c | 6 +++---
2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 52269e56c514..e61cf3f609b4 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2863,6 +2863,23 @@ extern long copy_huge_page_from_user(struct page *dst_page,
const void __user *usr_src,
unsigned int pages_per_huge_page,
bool allow_pagefault);
+
+/**
+ * vma_is_special_huge - Are transhuge page-table entries considered special?
+ * @vma: Pointer to the struct vm_area_struct to consider
+ *
+ * Whether transhuge page-table entries are considered "special" following
+ * the definition in vm_normal_page().
+ *
+ * Return: true if transhuge page-table entries should be considered special,
+ * false otherwise.
+ */
+static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
+{
+ return vma_is_dax(vma) || (vma->vm_file &&
+ (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
+}
+
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
#ifdef CONFIG_DEBUG_PAGEALLOC
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b08b199f9a11..ff7a8b85c3ba 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1802,7 +1802,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
orig_pmd = pmdp_huge_get_and_clear_full(tlb->mm, addr, pmd,
tlb->fullmm);
tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
- if (vma_is_dax(vma)) {
+ if (vma_is_special_huge(vma)) {
if (arch_needs_pgtable_deposit())
zap_deposited_table(tlb->mm, pmd);
spin_unlock(ptl);
@@ -2066,7 +2066,7 @@ int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma,
*/
pudp_huge_get_and_clear_full(tlb->mm, addr, pud, tlb->fullmm);
tlb_remove_pud_tlb_entry(tlb, pud, addr);
- if (vma_is_dax(vma)) {
+ if (vma_is_special_huge(vma)) {
spin_unlock(ptl);
/* No zero page support yet */
} else {
@@ -2175,7 +2175,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd,
*/
if (arch_needs_pgtable_deposit())
zap_deposited_table(mm, pmd);
- if (vma_is_dax(vma))
+ if (vma_is_special_huge(vma))
return;
page = pmd_page(_pmd);
if (!PageDirty(page) && pmd_dirty(_pmd))
--
2.21.1
From: Thomas Hellstrom <[email protected]>
Using huge page-table entries requires that the physical address of the
start of a buffer object is huge page size aligned.
Make a special version of the TTM range manager that accomplishes this,
but falls back to a smaller page size alignment (PUD->PMD, PMD->NORMAL)
to avoid eviction.
If other drivers want to use it in the future, it can be made a
TTM generic helper. Note that drivers can force eviction for a certain
alignment by assigning the TTM GPU alignment correspondingly.
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Acked-by: Christian König <[email protected]>
---
drivers/gpu/drm/vmwgfx/Makefile | 1 +
drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 7 ++
drivers/gpu/drm/vmwgfx/vmwgfx_thp.c | 166 ++++++++++++++++++++++++++++
3 files changed, 174 insertions(+)
create mode 100644 drivers/gpu/drm/vmwgfx/vmwgfx_thp.c
diff --git a/drivers/gpu/drm/vmwgfx/Makefile b/drivers/gpu/drm/vmwgfx/Makefile
index c877a21a0739..421dd2a497a5 100644
--- a/drivers/gpu/drm/vmwgfx/Makefile
+++ b/drivers/gpu/drm/vmwgfx/Makefile
@@ -11,4 +11,5 @@ vmwgfx-y := vmwgfx_execbuf.o vmwgfx_gmr.o vmwgfx_kms.o vmwgfx_drv.o \
vmwgfx_validation.o vmwgfx_page_dirty.o \
ttm_object.o ttm_lock.o
+vmwgfx-$(CONFIG_TRANSPARENT_HUGEPAGE) += vmwgfx_thp.o
obj-$(CONFIG_DRM_VMWGFX) := vmwgfx.o
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index bb2757c98f0a..fe5b7293b8d1 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -1435,6 +1435,13 @@ vm_fault_t vmw_bo_vm_huge_fault(struct vm_fault *vmf,
enum page_entry_size pe_size);
#endif
+/* Transparent hugepage support - vmwgfx_thp.c */
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+extern const struct ttm_mem_type_manager_func vmw_thp_func;
+#else
+#define vmw_thp_func ttm_bo_manager_func
+#endif
+
/**
* VMW_DEBUG_KMS - Debug output for kernel mode-setting
*
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_thp.c b/drivers/gpu/drm/vmwgfx/vmwgfx_thp.c
new file mode 100644
index 000000000000..b7c816ba7166
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_thp.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Huge page-table-entry support for IO memory.
+ *
+ * Copyright (C) 2007-2019 Vmware, Inc. All rights reservedd.
+ */
+#include "vmwgfx_drv.h"
+#include <drm/ttm/ttm_module.h>
+#include <drm/ttm/ttm_bo_driver.h>
+#include <drm/ttm/ttm_placement.h>
+
+/**
+ * struct vmw_thp_manager - Range manager implementing huge page alignment
+ *
+ * @mm: The underlying range manager. Protected by @lock.
+ * @lock: Manager lock.
+ */
+struct vmw_thp_manager {
+ struct drm_mm mm;
+ spinlock_t lock;
+};
+
+static int vmw_thp_insert_aligned(struct drm_mm *mm, struct drm_mm_node *node,
+ unsigned long align_pages,
+ const struct ttm_place *place,
+ struct ttm_mem_reg *mem,
+ unsigned long lpfn,
+ enum drm_mm_insert_mode mode)
+{
+ if (align_pages >= mem->page_alignment &&
+ (!mem->page_alignment || align_pages % mem->page_alignment == 0)) {
+ return drm_mm_insert_node_in_range(mm, node,
+ mem->num_pages,
+ align_pages, 0,
+ place->fpfn, lpfn, mode);
+ }
+
+ return -ENOSPC;
+}
+
+static int vmw_thp_get_node(struct ttm_mem_type_manager *man,
+ struct ttm_buffer_object *bo,
+ const struct ttm_place *place,
+ struct ttm_mem_reg *mem)
+{
+ struct vmw_thp_manager *rman = (struct vmw_thp_manager *) man->priv;
+ struct drm_mm *mm = &rman->mm;
+ struct drm_mm_node *node;
+ unsigned long align_pages;
+ unsigned long lpfn;
+ enum drm_mm_insert_mode mode = DRM_MM_INSERT_BEST;
+ int ret;
+
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ lpfn = place->lpfn;
+ if (!lpfn)
+ lpfn = man->size;
+
+ mode = DRM_MM_INSERT_BEST;
+ if (place->flags & TTM_PL_FLAG_TOPDOWN)
+ mode = DRM_MM_INSERT_HIGH;
+
+ spin_lock(&rman->lock);
+ if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) {
+ align_pages = (HPAGE_PUD_SIZE >> PAGE_SHIFT);
+ if (mem->num_pages >= align_pages) {
+ ret = vmw_thp_insert_aligned(mm, node, align_pages,
+ place, mem, lpfn, mode);
+ if (!ret)
+ goto found_unlock;
+ }
+ }
+
+ align_pages = (HPAGE_PMD_SIZE >> PAGE_SHIFT);
+ if (mem->num_pages >= align_pages) {
+ ret = vmw_thp_insert_aligned(mm, node, align_pages, place, mem,
+ lpfn, mode);
+ if (!ret)
+ goto found_unlock;
+ }
+
+ ret = drm_mm_insert_node_in_range(mm, node, mem->num_pages,
+ mem->page_alignment, 0,
+ place->fpfn, lpfn, mode);
+found_unlock:
+ spin_unlock(&rman->lock);
+
+ if (unlikely(ret)) {
+ kfree(node);
+ } else {
+ mem->mm_node = node;
+ mem->start = node->start;
+ }
+
+ return 0;
+}
+
+
+
+static void vmw_thp_put_node(struct ttm_mem_type_manager *man,
+ struct ttm_mem_reg *mem)
+{
+ struct vmw_thp_manager *rman = (struct vmw_thp_manager *) man->priv;
+
+ if (mem->mm_node) {
+ spin_lock(&rman->lock);
+ drm_mm_remove_node(mem->mm_node);
+ spin_unlock(&rman->lock);
+
+ kfree(mem->mm_node);
+ mem->mm_node = NULL;
+ }
+}
+
+static int vmw_thp_init(struct ttm_mem_type_manager *man,
+ unsigned long p_size)
+{
+ struct vmw_thp_manager *rman;
+
+ rman = kzalloc(sizeof(*rman), GFP_KERNEL);
+ if (!rman)
+ return -ENOMEM;
+
+ drm_mm_init(&rman->mm, 0, p_size);
+ spin_lock_init(&rman->lock);
+ man->priv = rman;
+ return 0;
+}
+
+static int vmw_thp_takedown(struct ttm_mem_type_manager *man)
+{
+ struct vmw_thp_manager *rman = (struct vmw_thp_manager *) man->priv;
+ struct drm_mm *mm = &rman->mm;
+
+ spin_lock(&rman->lock);
+ if (drm_mm_clean(mm)) {
+ drm_mm_takedown(mm);
+ spin_unlock(&rman->lock);
+ kfree(rman);
+ man->priv = NULL;
+ return 0;
+ }
+ spin_unlock(&rman->lock);
+ return -EBUSY;
+}
+
+static void vmw_thp_debug(struct ttm_mem_type_manager *man,
+ struct drm_printer *printer)
+{
+ struct vmw_thp_manager *rman = (struct vmw_thp_manager *) man->priv;
+
+ spin_lock(&rman->lock);
+ drm_mm_print(&rman->mm, printer);
+ spin_unlock(&rman->lock);
+}
+
+const struct ttm_mem_type_manager_func vmw_thp_func = {
+ .init = vmw_thp_init,
+ .takedown = vmw_thp_takedown,
+ .get_node = vmw_thp_get_node,
+ .put_node = vmw_thp_put_node,
+ .debug = vmw_thp_debug
+};
--
2.21.1
From: Thomas Hellstrom <[email protected]>
Start using the helpers that align buffer object user-space addresses and
buffer object vram addresses to huge page boundaries.
This is to improve the chances of allowing huge page-table entries.
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Acked-by: Christian König <[email protected]>
---
drivers/gpu/drm/drm_file.c | 1 +
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 13 +++++++++++++
drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 1 +
drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c | 2 +-
4 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index 77e691202b52..b29a72b68068 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -935,4 +935,5 @@ unsigned long drm_get_unmapped_area(struct file *file,
return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+EXPORT_SYMBOL_GPL(drm_get_unmapped_area);
#endif /* CONFIG_MMU */
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 827458f49112..77d85bc54ef0 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -1223,6 +1223,18 @@ static void vmw_remove(struct pci_dev *pdev)
pci_disable_device(pdev);
}
+static unsigned long
+vmw_get_unmapped_area(struct file *file, unsigned long uaddr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct drm_file *file_priv = file->private_data;
+ struct vmw_private *dev_priv = vmw_priv(file_priv->minor->dev);
+
+ return drm_get_unmapped_area(file, uaddr, len, pgoff, flags,
+ &dev_priv->vma_manager);
+}
+
static int vmwgfx_pm_notifier(struct notifier_block *nb, unsigned long val,
void *ptr)
{
@@ -1394,6 +1406,7 @@ static const struct file_operations vmwgfx_driver_fops = {
.compat_ioctl = vmw_compat_ioctl,
#endif
.llseek = noop_llseek,
+ .get_unmapped_area = vmw_get_unmapped_area,
};
static struct drm_driver driver = {
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index fe5b7293b8d1..4853bd95bf54 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -929,6 +929,7 @@ extern int vmw_mmap(struct file *filp, struct vm_area_struct *vma);
extern void vmw_validation_mem_init_ttm(struct vmw_private *dev_priv,
size_t gran);
+
/**
* TTM buffer object driver - vmwgfx_ttm_buffer.c
*/
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c
index d8ea3dd10af0..34c721ab3ff3 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c
@@ -754,7 +754,7 @@ static int vmw_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
break;
case TTM_PL_VRAM:
/* "On-card" video ram */
- man->func = &ttm_bo_manager_func;
+ man->func = &vmw_thp_func;
man->gpu_offset = 0;
man->flags = TTM_MEMTYPE_FLAG_FIXED | TTM_MEMTYPE_FLAG_MAPPABLE;
man->available_caching = TTM_PL_FLAG_CACHED;
--
2.21.1
From: Thomas Hellstrom <[email protected]>
For graphics drivers needing to modify the page-protection, add
huge page-table entries counterparts to vmf_insert_pfn_prot().
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Acked-by: Christian König <[email protected]>
---
include/linux/huge_mm.h | 41 +++++++++++++++++++++++++++++++++++++++--
mm/huge_memory.c | 38 ++++++++++++++++++++++++++++++++------
2 files changed, 71 insertions(+), 8 deletions(-)
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 5aca3d1bdb32..f63b0882c1b3 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -47,8 +47,45 @@ extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, pgprot_t newprot,
int prot_numa);
-vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write);
-vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write);
+vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn,
+ pgprot_t pgprot, bool write);
+
+/**
+ * vmf_insert_pfn_pmd - insert a pmd size pfn
+ * @vmf: Structure describing the fault
+ * @pfn: pfn to insert
+ * @pgprot: page protection to use
+ * @write: whether it's a write fault
+ *
+ * Insert a pmd size pfn. See vmf_insert_pfn() for additional info.
+ *
+ * Return: vm_fault_t value.
+ */
+static inline vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn,
+ bool write)
+{
+ return vmf_insert_pfn_pmd_prot(vmf, pfn, vmf->vma->vm_page_prot, write);
+}
+vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn,
+ pgprot_t pgprot, bool write);
+
+/**
+ * vmf_insert_pfn_pud - insert a pud size pfn
+ * @vmf: Structure describing the fault
+ * @pfn: pfn to insert
+ * @pgprot: page protection to use
+ * @write: whether it's a write fault
+ *
+ * Insert a pud size pfn. See vmf_insert_pfn() for additional info.
+ *
+ * Return: vm_fault_t value.
+ */
+static inline vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn,
+ bool write)
+{
+ return vmf_insert_pfn_pud_prot(vmf, pfn, vmf->vma->vm_page_prot, write);
+}
+
enum transparent_hugepage_flag {
TRANSPARENT_HUGEPAGE_FLAG,
TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index ff7a8b85c3ba..e7c69882861d 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -824,11 +824,24 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
pte_free(mm, pgtable);
}
-vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write)
+/**
+ * vmf_insert_pfn_pmd_prot - insert a pmd size pfn
+ * @vmf: Structure describing the fault
+ * @pfn: pfn to insert
+ * @pgprot: page protection to use
+ * @write: whether it's a write fault
+ *
+ * Insert a pmd size pfn. See vmf_insert_pfn() for additional info and
+ * also consult the vmf_insert_mixed_prot() documentation when
+ * @pgprot != @vmf->vma->vm_page_prot.
+ *
+ * Return: vm_fault_t value.
+ */
+vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn,
+ pgprot_t pgprot, bool write)
{
unsigned long addr = vmf->address & PMD_MASK;
struct vm_area_struct *vma = vmf->vma;
- pgprot_t pgprot = vma->vm_page_prot;
pgtable_t pgtable = NULL;
/*
@@ -856,7 +869,7 @@ vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write)
insert_pfn_pmd(vma, addr, vmf->pmd, pfn, pgprot, write, pgtable);
return VM_FAULT_NOPAGE;
}
-EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd);
+EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd_prot);
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
static pud_t maybe_pud_mkwrite(pud_t pud, struct vm_area_struct *vma)
@@ -902,11 +915,24 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
spin_unlock(ptl);
}
-vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write)
+/**
+ * vmf_insert_pfn_pud_prot - insert a pud size pfn
+ * @vmf: Structure describing the fault
+ * @pfn: pfn to insert
+ * @pgprot: page protection to use
+ * @write: whether it's a write fault
+ *
+ * Insert a pud size pfn. See vmf_insert_pfn() for additional info and
+ * also consult the vmf_insert_mixed_prot() documentation when
+ * @pgprot != @vmf->vma->vm_page_prot.
+ *
+ * Return: vm_fault_t value.
+ */
+vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn,
+ pgprot_t pgprot, bool write)
{
unsigned long addr = vmf->address & PUD_MASK;
struct vm_area_struct *vma = vmf->vma;
- pgprot_t pgprot = vma->vm_page_prot;
/*
* If we had pud_special, we could avoid all these restrictions,
@@ -927,7 +953,7 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write)
insert_pfn_pud(vma, addr, vmf->pud, pfn, pgprot, write);
return VM_FAULT_NOPAGE;
}
-EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud);
+EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud_prot);
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
static void touch_pmd(struct vm_area_struct *vma, unsigned long addr,
--
2.21.1
From: Thomas Hellstrom <[email protected]>
The functions wp_huge_pmd() and wp_huge_pud() currently relies on the
huge_fault() callback to split huge page table entries if needed.
However for module users that requires export of the split_huge_xxx()
functionality which may be undesired. Instead split pre-existing huge
page-table entries on VM_FAULT_FALLBACK return.
We currently only do COW and write-notify on the PTE level, so if the
huge_fault() handler returns VM_FAULT_FALLBACK on wp faults,
split the huge pages and page-table entries. Also do this for huge PUDs
if there is no huge_fault() handler and the vma is not anonymous, similar
to how it's done for PMDs.
Note that fs/dax.c still does the splitting in the huge_fault() handler, but as
huge_fault() A follow-up patch can remove the dax.c split_huge_pmd() if needed.
Cc: Andrew Morton <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: "Jérôme Glisse" <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: Dan Williams <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Acked-by: Christian König <[email protected]>
---
mm/memory.c | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index 0bccc622e482..1e3fc1988790 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3932,11 +3932,14 @@ static inline vm_fault_t wp_huge_pmd(struct vm_fault *vmf, pmd_t orig_pmd)
{
if (vma_is_anonymous(vmf->vma))
return do_huge_pmd_wp_page(vmf, orig_pmd);
- if (vmf->vma->vm_ops->huge_fault)
- return vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PMD);
+ if (vmf->vma->vm_ops->huge_fault) {
+ vm_fault_t ret = vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PMD);
- /* COW handled on pte level: split pmd */
- VM_BUG_ON_VMA(vmf->vma->vm_flags & VM_SHARED, vmf->vma);
+ if (!(ret & VM_FAULT_FALLBACK))
+ return ret;
+ }
+
+ /* COW or write-notify handled on pte level: split pmd. */
__split_huge_pmd(vmf->vma, vmf->pmd, vmf->address, false, NULL);
return VM_FAULT_FALLBACK;
@@ -3949,12 +3952,20 @@ static inline bool vma_is_accessible(struct vm_area_struct *vma)
static vm_fault_t create_huge_pud(struct vm_fault *vmf)
{
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
+ defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
/* No support for anonymous transparent PUD pages yet */
if (vma_is_anonymous(vmf->vma))
- return VM_FAULT_FALLBACK;
- if (vmf->vma->vm_ops->huge_fault)
- return vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PUD);
+ goto split;
+ if (vmf->vma->vm_ops->huge_fault) {
+ vm_fault_t ret = vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PUD);
+
+ if (!(ret & VM_FAULT_FALLBACK))
+ return ret;
+ }
+split:
+ /* COW or write-notify not handled on PUD level: split pud.*/
+ __split_huge_pud(vmf->vma, vmf->pud, vmf->address);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
return VM_FAULT_FALLBACK;
}
--
2.21.1
On 3/4/20 11:28 AM, Thomas Hellström (VMware) wrote:
> In order to reduce CPU usage [1] and in theory TLB misses this patchset enables
> huge- and giant page-table entries for TTM and TTM-enabled graphics drivers.
>
> Patch 1 and 2 introduce a vma_is_special_huge() function to make the mm code
> take the same path as DAX when splitting huge- and giant page table entries,
> (which currently means zapping the page-table entry and rely on re-faulting).
>
> Patch 3 makes the mm code split existing huge page-table entries
> on huge_fault fallbacks. Typically on COW or on buffer-objects that want
> write-notify. COW and write-notification is always done on the lowest
> page-table level. See the patch log message for additional considerations.
>
> Patch 4 introduces functions to allow the graphics drivers to manipulate
> the caching- and encryption flags of huge page-table entries without ugly
> hacks.
>
> Patch 5 implements the huge_fault handler in TTM.
> This enables huge page-table entries, provided that the kernel is configured
> to support transhuge pages, either by default or using madvise().
> However, they are unlikely to be inserted unless the kernel buffer object
> pfns and user-space addresses align perfectly. There are various options
> here, but since buffer objects that reside in system pages typically start
> at huge page boundaries if they are backed by huge pages, we try to enforce
> buffer object starting pfns and user-space addresses to be huge page-size
> aligned if their size exceeds a huge page-size. If pud-size transhuge
> ("giant") pages are enabled by the arch, the same holds for those.
>
> Patch 6 implements a specialized huge_fault handler for vmwgfx.
> The vmwgfx driver may perform dirty-tracking and needs some special code
> to handle that correctly.
>
> Patch 7 implements a drm helper to align user-space addresses according
> to the above scheme, if possible.
>
> Patch 8 implements a TTM range manager for vmwgfx that does the same for
> graphics IO memory. This may later be reused by other graphics drivers
> if necessary.
>
> Patch 9 finally hooks up the helpers of patch 7 and 8 to the vmwgfx driver.
> A similar change is needed for graphics drivers that want a reasonable
> likelyhood of actually using huge page-table entries.
>
> If a buffer object size is not huge-page or giant-page aligned,
> its size will NOT be inflated by this patchset. This means that the buffer
> object tail will use smaller size page-table entries and thus no memory
> overhead occurs. Drivers that want to pay the memory overhead price need to
> implement their own scheme to inflate buffer-object sizes.
>
> PMD size huge page-table-entries have been tested with vmwgfx and found to
> work well both with system memory backed and IO memory backed buffer objects.
>
> PUD size giant page-table-entries have seen limited (fault and COW) testing
> using a modified kernel (to support 1GB page allocations) and a fake vmwgfx
> TTM memory type. The vmwgfx driver does otherwise not support 1GB-size IO
> memory resources.
>
> Comments and suggestions welcome.
> Thomas
>
> Changes since RFC:
> * Check for buffer objects present in contigous IO Memory (Christian König)
> * Rebased on the vmwgfx emulated coherent memory functionality. That rebase
> adds patch 5.
> Changes since v1:
> * Make the new TTM range manager vmwgfx-specific. (Christian König)
> * Minor fixes for configs that don't support or only partially support
> transhuge pages.
> Changes since v2:
> * Minor coding style and doc fixes in patch 5/9 (Christian König)
> * Patch 5/9 doesn't touch mm. Remove from the patch title.
> Changes since v3:
> * Added reviews and acks
> * Implemented ugly but generic ttm_pgprot_is_wrprotecting() instead of arch
> specific code.
> Changes since v4:
> * Added timings (Andrew Morton)
> * Updated function documentation (Andrew Morton)
> Changes since v6:
> * Fix drm build error with !CONFIG_MMU
>
> [1]
> The below test program generates the following gnu time output when run on a
> vmwgfx-enabled kernel without the patch series:
>
> 4.78user 6.02system 0:10.91elapsed 99%CPU (0avgtext+0avgdata 1624maxresident)k
> 0inputs+0outputs (0major+640077minor)pagefaults 0swaps
>
> and with the patch series:
>
> 1.71user 3.60system 0:05.40elapsed 98%CPU (0avgtext+0avgdata 1656maxresident)k
> 0inputs+0outputs (0major+20079minor)pagefaults 0swaps
>
> A consistent number of reduced graphics page-faults can be seen with normal
> graphics applications, but due to the aggressive buffer object caching in
> vmwgfx user-space drivers the CPU time reduction is within the error marginal.
>
> #include <unistd.h>
> #include <string.h>
> #include <sys/mman.h>
> #include <xf86drm.h>
>
> static void checkerr(int ret, const char *name)
> {
> if (ret < 0) {
> perror(name);
> exit(-1);
> }
> }
>
> int main(int agc, const char *argv[])
> {
> struct drm_mode_create_dumb c_arg = {0};
> struct drm_mode_map_dumb m_arg = {0};
> struct drm_mode_destroy_dumb d_arg = {0};
> int ret, i, fd;
> void *map;
>
> fd = open("/dev/dri/card0", O_RDWR);
> checkerr(fd, argv[0]);
>
> for (i = 0; i < 10000; ++i) {
> c_arg.bpp = 32;
> c_arg.width = 1024;
> c_arg.height = 1024;
> ret = drmIoctl(fd, DRM_IOCTL_MODE_CREATE_DUMB, &c_arg);
> checkerr(fd, argv[0]);
>
> m_arg.handle = c_arg.handle;
> ret = drmIoctl(fd, DRM_IOCTL_MODE_MAP_DUMB, &m_arg);
> checkerr(fd, argv[0]);
>
> map = mmap(NULL, c_arg.size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
> m_arg.offset);
> checkerr(map == MAP_FAILED ? -1 : 0, argv[0]);
>
> (void) madvise((void *) map, c_arg.size, MADV_HUGEPAGE);
> memset(map, 0x67, c_arg.size);
> munmap(map, c_arg.size);
>
> d_arg.handle = c_arg.handle;
> ret = drmIoctl(fd, DRM_IOCTL_MODE_DESTROY_DUMB, &d_arg);
> checkerr(ret, argv[0]);
> }
>
> close(fd);
> }
>
> Cc: Andrew Morton <[email protected]>
> Cc: Michal Hocko <[email protected]>
> Cc: "Matthew Wilcox (Oracle)" <[email protected]>
> Cc: "Kirill A. Shutemov" <[email protected]>
> Cc: Ralph Campbell <[email protected]>
> Cc: "Jérôme Glisse" <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: Dan Williams <[email protected]>
>
>
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Andrew, would it be possible to have an ack for merge using a DRM tree
for the -mm patches?
Thanks,
Thomas
On Mon, 16 Mar 2020 13:32:08 +0100 Thomas Hellstr?m (VMware) <[email protected]> wrote:
> > _______________________________________________
> > dri-devel mailing list
> > [email protected]
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
>
> Andrew, would it be possible to have an ack for merge using a DRM tree
> for the -mm patches?
Yes, please do. It's all pretty straightforward addition of new
functionality which won't affect existing code.
On 3/19/20 12:27 AM, Andrew Morton wrote:
> On Mon, 16 Mar 2020 13:32:08 +0100 Thomas Hellström (VMware) <[email protected]> wrote:
>
>>> _______________________________________________
>>> dri-devel mailing list
>>> [email protected]
>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>> Andrew, would it be possible to have an ack for merge using a DRM tree
>> for the -mm patches?
> Yes, please do. It's all pretty straightforward addition of new
> functionality which won't affect existing code.
Thanks Andrew. Can I add your Acked-by: To the mm patches for Linus'
reference?
Thanks,
Thomas
On Thu, 19 Mar 2020 11:20:44 +0100 Thomas Hellstr?m (VMware) <[email protected]> wrote:
> On 3/19/20 12:27 AM, Andrew Morton wrote:
> > On Mon, 16 Mar 2020 13:32:08 +0100 Thomas Hellstr?m (VMware) <[email protected]> wrote:
> >
> >>> _______________________________________________
> >>> dri-devel mailing list
> >>> [email protected]
> >>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
> >> Andrew, would it be possible to have an ack for merge using a DRM tree
> >> for the -mm patches?
> > Yes, please do. It's all pretty straightforward addition of new
> > functionality which won't affect existing code.
>
> Thanks Andrew. Can I add your Acked-by: To the mm patches for Linus'
> reference?
>
Please do.