2019-07-31 02:09:44

by John Hubbard

[permalink] [raw]
Subject: [PATCH v4 0/3] mm/gup: add make_dirty arg to put_user_pages_dirty_lock()

From: John Hubbard <[email protected]>

Changes since v3:

* Fixed an unused variable warning in siw_mem.c

Changes since v2:

* Critical bug fix: remove a stray "break;" from the new routine.

Changes since v1:

* Instead of providing __put_user_pages(), add an argument to
put_user_pages_dirty_lock(), and delete put_user_pages_dirty().
This is based on the following points:

1. Lots of call sites become simpler if a bool is passed
into put_user_page*(), instead of making the call site
choose which put_user_page*() variant to call.

2. Christoph Hellwig's observation that set_page_dirty_lock()
is usually correct, and set_page_dirty() is usually a
bug, or at least questionable, within a put_user_page*()
calling chain.

* Added the Infiniband driver back to the patch series, because it is
a caller of put_user_pages_dirty_lock().

Unchanged parts from the v1 cover letter (except for the diffstat):

Notes about the remaining patches to come:

There are about 50+ patches in my tree [2], and I'll be sending out the
remaining ones in a few more groups:

* The block/bio related changes (Jerome mostly wrote those, but I've
had to move stuff around extensively, and add a little code)

* mm/ changes

* other subsystem patches

* an RFC that shows the current state of the tracking patch set. That
can only be applied after all call sites are converted, but it's
good to get an early look at it.

This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
("mm: introduce put_user_page*(), placeholder versions").

John Hubbard (3):
mm/gup: add make_dirty arg to put_user_pages_dirty_lock()
drivers/gpu/drm/via: convert put_page() to put_user_page*()
net/xdp: convert put_page() to put_user_page*()

drivers/gpu/drm/via/via_dmablit.c | 10 +-
drivers/infiniband/core/umem.c | 5 +-
drivers/infiniband/hw/hfi1/user_pages.c | 5 +-
drivers/infiniband/hw/qib/qib_user_pages.c | 5 +-
drivers/infiniband/hw/usnic/usnic_uiom.c | 5 +-
drivers/infiniband/sw/siw/siw_mem.c | 10 +-
include/linux/mm.h | 5 +-
mm/gup.c | 115 +++++++++------------
net/xdp/xdp_umem.c | 9 +-
9 files changed, 61 insertions(+), 108 deletions(-)

--
2.22.0


2019-07-31 02:09:46

by John Hubbard

[permalink] [raw]
Subject: [PATCH v4 3/3] net/xdp: convert put_page() to put_user_page*()

From: John Hubbard <[email protected]>

For pages that were retained via get_user_pages*(), release those pages
via the new put_user_page*() routines, instead of via put_page() or
release_pages().

This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
("mm: introduce put_user_page*(), placeholder versions").

Cc: Björn Töpel <[email protected]>
Cc: Magnus Karlsson <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: [email protected]
Signed-off-by: John Hubbard <[email protected]>
---
net/xdp/xdp_umem.c | 9 +--------
1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index 83de74ca729a..17c4b3d3dc34 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -166,14 +166,7 @@ void xdp_umem_clear_dev(struct xdp_umem *umem)

static void xdp_umem_unpin_pages(struct xdp_umem *umem)
{
- unsigned int i;
-
- for (i = 0; i < umem->npgs; i++) {
- struct page *page = umem->pgs[i];
-
- set_page_dirty_lock(page);
- put_page(page);
- }
+ put_user_pages_dirty_lock(umem->pgs, umem->npgs, true);

kfree(umem->pgs);
umem->pgs = NULL;
--
2.22.0

2019-07-31 08:13:23

by Björn Töpel

[permalink] [raw]
Subject: Re: [PATCH v4 3/3] net/xdp: convert put_page() to put_user_page*()

On 2019-07-30 22:57, [email protected] wrote:
> From: John Hubbard <[email protected]>
>
> For pages that were retained via get_user_pages*(), release those pages
> via the new put_user_page*() routines, instead of via put_page() or
> release_pages().
>
> This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
> ("mm: introduce put_user_page*(), placeholder versions").
>
> Cc: Björn Töpel <[email protected]>
> Cc: Magnus Karlsson <[email protected]>
> Cc: David S. Miller <[email protected]>
> Cc: [email protected]
> Signed-off-by: John Hubbard <[email protected]>

Acked-by: Björn Töpel <[email protected]>

> ---
> net/xdp/xdp_umem.c | 9 +--------
> 1 file changed, 1 insertion(+), 8 deletions(-)
>
> diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
> index 83de74ca729a..17c4b3d3dc34 100644
> --- a/net/xdp/xdp_umem.c
> +++ b/net/xdp/xdp_umem.c
> @@ -166,14 +166,7 @@ void xdp_umem_clear_dev(struct xdp_umem *umem)
>
> static void xdp_umem_unpin_pages(struct xdp_umem *umem)
> {
> - unsigned int i;
> -
> - for (i = 0; i < umem->npgs; i++) {
> - struct page *page = umem->pgs[i];
> -
> - set_page_dirty_lock(page);
> - put_page(page);
> - }
> + put_user_pages_dirty_lock(umem->pgs, umem->npgs, true);
>
> kfree(umem->pgs);
> umem->pgs = NULL;
>