From: Kairui Song <kasong@tencent.com>
No feature change, simply move the routine to a standalone function to
be re-used later. The error path handling is copied from the "out_page"
label, to make the code change minimized for easier reviewing.
Signed-off-by: Kairui Song <kasong@tencent.com>
---
mm/memory.c | 32 ++++----------------------------
mm/swap.h | 8 ++++++++
mm/swap_state.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 59 insertions(+), 28 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index a0a50d3754f0..0165c8cad489 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3803,7 +3803,6 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
swp_entry_t entry;
pte_t pte;
vm_fault_t ret = 0;
- void *shadow = NULL;
if (!pte_unmap_same(vmf))
goto out;
@@ -3867,33 +3866,10 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
if (!folio) {
if (data_race(si->flags & SWP_SYNCHRONOUS_IO) &&
__swap_count(entry) == 1) {
- /* skip swapcache */
- folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
- vma, vmf->address, false);
- page = &folio->page;
- if (folio) {
- __folio_set_locked(folio);
- __folio_set_swapbacked(folio);
-
- if (mem_cgroup_swapin_charge_folio(folio,
- vma->vm_mm, GFP_KERNEL,
- entry)) {
- ret = VM_FAULT_OOM;
- goto out_page;
- }
- mem_cgroup_swapin_uncharge_swap(entry);
-
- shadow = get_shadow_from_swap_cache(entry);
- if (shadow)
- workingset_refault(folio, shadow);
-
- folio_add_lru(folio);
-
- /* To provide entry to swap_read_folio() */
- folio->swap = entry;
- swap_read_folio(folio, true, NULL);
- folio->private = NULL;
- }
+ /* skip swapcache and readahead */
+ folio = swapin_direct(entry, GFP_HIGHUSER_MOVABLE, vmf);
+ if (folio)
+ page = &folio->page;
} else {
page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
vmf);
diff --git a/mm/swap.h b/mm/swap.h
index 758c46ca671e..83eab7b67e77 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -56,6 +56,8 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
struct mempolicy *mpol, pgoff_t ilx);
struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
struct vm_fault *vmf);
+struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
+ struct vm_fault *vmf);
static inline unsigned int folio_swap_flags(struct folio *folio)
{
@@ -86,6 +88,12 @@ static inline struct folio *swap_cluster_readahead(swp_entry_t entry,
return NULL;
}
+struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
+ struct vm_fault *vmf)
+{
+ return NULL;
+}
+
static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
struct vm_fault *vmf)
{
diff --git a/mm/swap_state.c b/mm/swap_state.c
index e671266ad772..24cb93ed5081 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -861,6 +861,53 @@ static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,
return folio;
}
+/**
+ * swapin_direct - swap in folios skipping swap cache and readahead
+ * @entry: swap entry of this memory
+ * @gfp_mask: memory allocation flags
+ * @vmf: fault information
+ *
+ * Returns the struct folio for entry and addr after the swap entry is read
+ * in.
+ */
+struct folio *swapin_direct(swp_entry_t entry, gfp_t gfp_mask,
+ struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct folio *folio;
+ void *shadow = NULL;
+
+ /* skip swapcache */
+ folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
+ vma, vmf->address, false);
+ if (folio) {
+ __folio_set_locked(folio);
+ __folio_set_swapbacked(folio);
+
+ if (mem_cgroup_swapin_charge_folio(folio,
+ vma->vm_mm, GFP_KERNEL,
+ entry)) {
+ folio_unlock(folio);
+ folio_put(folio);
+ return NULL;
+ }
+ mem_cgroup_swapin_uncharge_swap(entry);
+
+ shadow = get_shadow_from_swap_cache(entry);
+ if (shadow)
+ workingset_refault(folio, shadow);
+
+ folio_add_lru(folio);
+
+ /* To provide entry to swap_read_folio() */
+ folio->swap = entry;
+ swap_read_folio(folio, true, NULL);
+ folio->private = NULL;
+ }
+
+ return folio;
+}
+
/**
* swapin_readahead - swap in pages in hope we need them soon
* @entry: swap entry of this memory
--
2.43.0Kairui Song <ryncsn@gmail.com> writes:
> From: Kairui Song <kasong@tencent.com>
>
> No feature change, simply move the routine to a standalone function to
> be re-used later. The error path handling is copied from the "out_page"
> label, to make the code change minimized for easier reviewing.
>
> Signed-off-by: Kairui Song <kasong@tencent.com>
> ---
> mm/memory.c | 32 ++++----------------------------
> mm/swap.h | 8 ++++++++
> mm/swap_state.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 59 insertions(+), 28 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index a0a50d3754f0..0165c8cad489 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -3803,7 +3803,6 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> swp_entry_t entry;
> pte_t pte;
> vm_fault_t ret = 0;
> - void *shadow = NULL;
>
> if (!pte_unmap_same(vmf))
> goto out;
> @@ -3867,33 +3866,10 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> if (!folio) {
> if (data_race(si->flags & SWP_SYNCHRONOUS_IO) &&
> __swap_count(entry) == 1) {
> - /* skip swapcache */
> - folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
> - vma, vmf->address, false);
> - page = &folio->page;
> - if (folio) {
> - __folio_set_locked(folio);
> - __folio_set_swapbacked(folio);
> -
> - if (mem_cgroup_swapin_charge_folio(folio,
> - vma->vm_mm, GFP_KERNEL,
> - entry)) {
> - ret = VM_FAULT_OOM;
> - goto out_page;
> - }
> - mem_cgroup_swapin_uncharge_swap(entry);
> -
> - shadow = get_shadow_from_swap_cache(entry);
> - if (shadow)
> - workingset_refault(folio, shadow);
> -
> - folio_add_lru(folio);
> -
> - /* To provide entry to swap_read_folio() */
> - folio->swap = entry;
> - swap_read_folio(folio, true, NULL);
> - folio->private = NULL;
> - }
> + /* skip swapcache and readahead */
> + folio = swapin_direct(entry, GFP_HIGHUSER_MOVABLE, vmf);
> + if (folio)
> + page = &folio->page;
> } else {
> page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
> vmf);
> diff --git a/mm/swap.h b/mm/swap.h
> index 758c46ca671e..83eab7b67e77 100644
> --- a/mm/swap.h
> +++ b/mm/swap.h
> @@ -56,6 +56,8 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
> struct mempolicy *mpol, pgoff_t ilx);
> struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
> struct vm_fault *vmf);
> +struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
> + struct vm_fault *vmf);
>
> static inline unsigned int folio_swap_flags(struct folio *folio)
> {
> @@ -86,6 +88,12 @@ static inline struct folio *swap_cluster_readahead(swp_entry_t entry,
> return NULL;
> }
>
> +struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
> + struct vm_fault *vmf)
> +{
> + return NULL;
> +}
> +
> static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
> struct vm_fault *vmf)
> {
> diff --git a/mm/swap_state.c b/mm/swap_state.c
> index e671266ad772..24cb93ed5081 100644
> --- a/mm/swap_state.c
> +++ b/mm/swap_state.c
> @@ -861,6 +861,53 @@ static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,
> return folio;
> }
>
> +/**
> + * swapin_direct - swap in folios skipping swap cache and readahead
swap in a folio ...
> + * @entry: swap entry of this memory
> + * @gfp_mask: memory allocation flags
> + * @vmf: fault information
> + *
> + * Returns the struct folio for entry and addr after the swap entry is read
> + * in.
> + */
> +struct folio *swapin_direct(swp_entry_t entry, gfp_t gfp_mask,
> + struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct folio *folio;
> + void *shadow = NULL;
> +
> + /* skip swapcache */
> + folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
You passed gfp_mask in, but don't use it.
> + vma, vmf->address, false);
> + if (folio) {
> + __folio_set_locked(folio);
> + __folio_set_swapbacked(folio);
> +
> + if (mem_cgroup_swapin_charge_folio(folio,
> + vma->vm_mm, GFP_KERNEL,
> + entry)) {
> + folio_unlock(folio);
> + folio_put(folio);
> + return NULL;
> + }
> + mem_cgroup_swapin_uncharge_swap(entry);
> +
> + shadow = get_shadow_from_swap_cache(entry);
> + if (shadow)
> + workingset_refault(folio, shadow);
> +
> + folio_add_lru(folio);
> +
> + /* To provide entry to swap_read_folio() */
> + folio->swap = entry;
> + swap_read_folio(folio, true, NULL);
> + folio->private = NULL;
> + }
> +
> + return folio;
> +}
> +
> /**
> * swapin_readahead - swap in pages in hope we need them soon
> * @entry: swap entry of this memory
--
Best Regards,
Huang, Ying
Huang, Ying <ying.huang@intel.com> 于2024年1月4日周四 15:31写道：
>
> Kairui Song <ryncsn@gmail.com> writes:
>
> > From: Kairui Song <kasong@tencent.com>
> >
> > No feature change, simply move the routine to a standalone function to
> > be re-used later. The error path handling is copied from the "out_page"
> > label, to make the code change minimized for easier reviewing.
> >
> > Signed-off-by: Kairui Song <kasong@tencent.com>
> > ---
> > mm/memory.c | 32 ++++----------------------------
> > mm/swap.h | 8 ++++++++
> > mm/swap_state.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 59 insertions(+), 28 deletions(-)
> >
> > diff --git a/mm/memory.c b/mm/memory.c
> > index a0a50d3754f0..0165c8cad489 100644
> > --- a/mm/memory.c
> > +++ b/mm/memory.c
> > @@ -3803,7 +3803,6 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> > swp_entry_t entry;
> > pte_t pte;
> > vm_fault_t ret = 0;
> > - void *shadow = NULL;
> >
> > if (!pte_unmap_same(vmf))
> > goto out;
> > @@ -3867,33 +3866,10 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> > if (!folio) {
> > if (data_race(si->flags & SWP_SYNCHRONOUS_IO) &&
> > __swap_count(entry) == 1) {
> > - /* skip swapcache */
> > - folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
> > - vma, vmf->address, false);
> > - page = &folio->page;
> > - if (folio) {
> > - __folio_set_locked(folio);
> > - __folio_set_swapbacked(folio);
> > -
> > - if (mem_cgroup_swapin_charge_folio(folio,
> > - vma->vm_mm, GFP_KERNEL,
> > - entry)) {
> > - ret = VM_FAULT_OOM;
> > - goto out_page;
> > - }
> > - mem_cgroup_swapin_uncharge_swap(entry);
> > -
> > - shadow = get_shadow_from_swap_cache(entry);
> > - if (shadow)
> > - workingset_refault(folio, shadow);
> > -
> > - folio_add_lru(folio);
> > -
> > - /* To provide entry to swap_read_folio() */
> > - folio->swap = entry;
> > - swap_read_folio(folio, true, NULL);
> > - folio->private = NULL;
> > - }
> > + /* skip swapcache and readahead */
> > + folio = swapin_direct(entry, GFP_HIGHUSER_MOVABLE, vmf);
> > + if (folio)
> > + page = &folio->page;
> > } else {
> > page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
> > vmf);
> > diff --git a/mm/swap.h b/mm/swap.h
> > index 758c46ca671e..83eab7b67e77 100644
> > --- a/mm/swap.h
> > +++ b/mm/swap.h
> > @@ -56,6 +56,8 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
> > struct mempolicy *mpol, pgoff_t ilx);
> > struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
> > struct vm_fault *vmf);
> > +struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
> > + struct vm_fault *vmf);
> >
> > static inline unsigned int folio_swap_flags(struct folio *folio)
> > {
> > @@ -86,6 +88,12 @@ static inline struct folio *swap_cluster_readahead(swp_entry_t entry,
> > return NULL;
> > }
> >
> > +struct folio *swapin_direct(swp_entry_t entry, gfp_t flag,
> > + struct vm_fault *vmf)
> > +{
> > + return NULL;
> > +}
> > +
> > static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
> > struct vm_fault *vmf)
> > {
> > diff --git a/mm/swap_state.c b/mm/swap_state.c
> > index e671266ad772..24cb93ed5081 100644
> > --- a/mm/swap_state.c
> > +++ b/mm/swap_state.c
> > @@ -861,6 +861,53 @@ static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,
> > return folio;
> > }
> >
> > +/**
> > + * swapin_direct - swap in folios skipping swap cache and readahead
>
> swap in a folio ...
>
> > + * @entry: swap entry of this memory
> > + * @gfp_mask: memory allocation flags
> > + * @vmf: fault information
> > + *
> > + * Returns the struct folio for entry and addr after the swap entry is read
> > + * in.
> > + */
> > +struct folio *swapin_direct(swp_entry_t entry, gfp_t gfp_mask,
> > + struct vm_fault *vmf)
> > +{
> > + struct vm_area_struct *vma = vmf->vma;
> > + struct folio *folio;
> > + void *shadow = NULL;
> > +
> > + /* skip swapcache */
> > + folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
>
> You passed gfp_mask in, but don't use it.
>
Thanks, will fix these.
> --
> Best Regards,
> Huang, Ying
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