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* [PATCH v2 0/2] swap readahead clean up
@ 2017-11-01  7:15 ` Minchan Kim
  0 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

This patchset cleans up recent added vma-based readahead code via
unifying cluster-based readahead.

* From v1
  * renamed swap_cluster_readahead - Huang
  * remove unnecessary extern declaration - Huang
  * add description for swapin_readahead - Huang

Minchan Kim (2):
  mm:swap: clean up swap readahead
  mm:swap: unify cluster-based and vma-based swap readahead

 include/linux/swap.h |  38 +++-----------
 mm/memory.c          |  24 +++------
 mm/shmem.c           |   5 +-
 mm/swap_state.c      | 137 ++++++++++++++++++++++++++++++++-------------------
 4 files changed, 103 insertions(+), 101 deletions(-)

-- 
2.7.4

^ permalink raw reply	[flat|nested] 6+ messages in thread
* [PATCH v2 0/2] swap readahead clean up
@ 2017-11-01  7:15 ` Minchan Kim
  0 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

This patchset cleans up recent added vma-based readahead code via
unifying cluster-based readahead.

* From v1
  * renamed swap_cluster_readahead - Huang
  * remove unnecessary extern declaration - Huang
  * add description for swapin_readahead - Huang

Minchan Kim (2):
  mm:swap: clean up swap readahead
  mm:swap: unify cluster-based and vma-based swap readahead

 include/linux/swap.h |  38 +++-----------
 mm/memory.c          |  24 +++------
 mm/shmem.c           |   5 +-
 mm/swap_state.c      | 137 ++++++++++++++++++++++++++++++++-------------------
 4 files changed, 103 insertions(+), 101 deletions(-)

-- 
2.7.4

--
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^ permalink raw reply	[flat|nested] 6+ messages in thread
* [PATCH v2 1/2] mm:swap: clean up swap readahead
  2017-11-01  7:15 ` Minchan Kim
@ 2017-11-01  7:15   ` Minchan Kim
  -1 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

When I see recent change of swap readahead, I am very unhappy
about current code structure which diverges two swap readahead
algorithm in do_swap_page. This patch is to clean it up.

Main motivation is that fault handler doesn't need to be aware of
readahead algorithms but just should call swapin_readahead.

As first step, this patch cleans up a little bit but not perfect
(I just separate for review easier) so next patch will make the goal
complete.

Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/swap.h | 17 ++--------
 mm/memory.c          | 17 +++-------
 mm/swap_state.c      | 89 ++++++++++++++++++++++++++++------------------------
 3 files changed, 55 insertions(+), 68 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 84255b3da7c1..7c7c8b344bc9 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -427,12 +427,8 @@ extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
 			bool *new_page_allocated);
 extern struct page *swapin_readahead(swp_entry_t, gfp_t,
 			struct vm_area_struct *vma, unsigned long addr);
-
-extern struct page *swap_readahead_detect(struct vm_fault *vmf,
-					  struct vma_swap_readahead *swap_ra);
 extern struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-					   struct vm_fault *vmf,
-					   struct vma_swap_readahead *swap_ra);
+					   struct vm_fault *vmf);
 
 /* linux/mm/swapfile.c */
 extern atomic_long_t nr_swap_pages;
@@ -551,15 +547,8 @@ static inline bool swap_use_vma_readahead(void)
 	return false;
 }
 
-static inline struct page *swap_readahead_detect(
-	struct vm_fault *vmf, struct vma_swap_readahead *swap_ra)
-{
-	return NULL;
-}
-
-static inline struct page *do_swap_page_readahead(
-	swp_entry_t fentry, gfp_t gfp_mask,
-	struct vm_fault *vmf, struct vma_swap_readahead *swap_ra)
+static inline struct page *do_swap_page_readahead(swp_entry_t fentry,
+				gfp_t gfp_mask, struct vm_fault *vmf)
 {
 	return NULL;
 }
diff --git a/mm/memory.c b/mm/memory.c
index 8a0c410037d2..e955298e4290 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2849,21 +2849,14 @@ int do_swap_page(struct vm_fault *vmf)
 	struct vm_area_struct *vma = vmf->vma;
 	struct page *page = NULL, *swapcache = NULL;
 	struct mem_cgroup *memcg;
-	struct vma_swap_readahead swap_ra;
 	swp_entry_t entry;
 	pte_t pte;
 	int locked;
 	int exclusive = 0;
 	int ret = 0;
-	bool vma_readahead = swap_use_vma_readahead();
 
-	if (vma_readahead)
-		page = swap_readahead_detect(vmf, &swap_ra);
-	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte)) {
-		if (page)
-			put_page(page);
+	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
 		goto out;
-	}
 
 	entry = pte_to_swp_entry(vmf->orig_pte);
 	if (unlikely(non_swap_entry(entry))) {
@@ -2889,9 +2882,7 @@ int do_swap_page(struct vm_fault *vmf)
 
 
 	delayacct_set_flag(DELAYACCT_PF_SWAPIN);
-	if (!page)
-		page = lookup_swap_cache(entry, vma_readahead ? vma : NULL,
-					 vmf->address);
+	page = lookup_swap_cache(entry, vma, vmf->address);
 	if (!page) {
 		struct swap_info_struct *si = swp_swap_info(entry);
 
@@ -2907,9 +2898,9 @@ int do_swap_page(struct vm_fault *vmf)
 				swap_readpage(page, true);
 			}
 		} else {
-			if (vma_readahead)
+			if (swap_use_vma_readahead())
 				page = do_swap_page_readahead(entry,
-					GFP_HIGHUSER_MOVABLE, vmf, &swap_ra);
+					GFP_HIGHUSER_MOVABLE, vmf);
 			else
 				page = swapin_readahead(entry,
 				       GFP_HIGHUSER_MOVABLE, vma, vmf->address);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 6c017ced11e6..e3c535fcd2df 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -331,32 +331,38 @@ struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma,
 			       unsigned long addr)
 {
 	struct page *page;
-	unsigned long ra_info;
-	int win, hits, readahead;
 
 	page = find_get_page(swap_address_space(entry), swp_offset(entry));
 
 	INC_CACHE_INFO(find_total);
 	if (page) {
+		bool vma_ra = swap_use_vma_readahead();
+		bool readahead = TestClearPageReadahead(page);
+
 		INC_CACHE_INFO(find_success);
 		if (unlikely(PageTransCompound(page)))
 			return page;
-		readahead = TestClearPageReadahead(page);
-		if (vma) {
-			ra_info = GET_SWAP_RA_VAL(vma);
-			win = SWAP_RA_WIN(ra_info);
-			hits = SWAP_RA_HITS(ra_info);
+
+		if (vma && vma_ra) {
+			unsigned long ra_val;
+			int win, hits;
+
+			ra_val = GET_SWAP_RA_VAL(vma);
+			win = SWAP_RA_WIN(ra_val);
+			hits = SWAP_RA_HITS(ra_val);
 			if (readahead)
 				hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX);
 			atomic_long_set(&vma->swap_readahead_info,
 					SWAP_RA_VAL(addr, win, hits));
 		}
+
 		if (readahead) {
 			count_vm_event(SWAP_RA_HIT);
-			if (!vma)
+			if (!vma || !vma_ra)
 				atomic_inc(&swapin_readahead_hits);
 		}
 	}
+
 	return page;
 }
 
@@ -645,16 +651,15 @@ static inline void swap_ra_clamp_pfn(struct vm_area_struct *vma,
 		    PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE));
 }
 
-struct page *swap_readahead_detect(struct vm_fault *vmf,
-				   struct vma_swap_readahead *swap_ra)
+static void swap_ra_info(struct vm_fault *vmf,
+			struct vma_swap_readahead *ra_info)
 {
 	struct vm_area_struct *vma = vmf->vma;
-	unsigned long swap_ra_info;
-	struct page *page;
+	unsigned long ra_val;
 	swp_entry_t entry;
 	unsigned long faddr, pfn, fpfn;
 	unsigned long start, end;
-	pte_t *pte;
+	pte_t *pte, *orig_pte;
 	unsigned int max_win, hits, prev_win, win, left;
 #ifndef CONFIG_64BIT
 	pte_t *tpte;
@@ -663,30 +668,32 @@ struct page *swap_readahead_detect(struct vm_fault *vmf,
 	max_win = 1 << min_t(unsigned int, READ_ONCE(page_cluster),
 			     SWAP_RA_ORDER_CEILING);
 	if (max_win == 1) {
-		swap_ra->win = 1;
-		return NULL;
+		ra_info->win = 1;
+		return;
 	}
 
 	faddr = vmf->address;
-	entry = pte_to_swp_entry(vmf->orig_pte);
-	if ((unlikely(non_swap_entry(entry))))
-		return NULL;
-	page = lookup_swap_cache(entry, vma, faddr);
-	if (page)
-		return page;
+	orig_pte = pte = pte_offset_map(vmf->pmd, faddr);
+	entry = pte_to_swp_entry(*pte);
+	if ((unlikely(non_swap_entry(entry)))) {
+		pte_unmap(orig_pte);
+		return;
+	}
 
 	fpfn = PFN_DOWN(faddr);
-	swap_ra_info = GET_SWAP_RA_VAL(vma);
-	pfn = PFN_DOWN(SWAP_RA_ADDR(swap_ra_info));
-	prev_win = SWAP_RA_WIN(swap_ra_info);
-	hits = SWAP_RA_HITS(swap_ra_info);
-	swap_ra->win = win = __swapin_nr_pages(pfn, fpfn, hits,
+	ra_val = GET_SWAP_RA_VAL(vma);
+	pfn = PFN_DOWN(SWAP_RA_ADDR(ra_val));
+	prev_win = SWAP_RA_WIN(ra_val);
+	hits = SWAP_RA_HITS(ra_val);
+	ra_info->win = win = __swapin_nr_pages(pfn, fpfn, hits,
 					       max_win, prev_win);
 	atomic_long_set(&vma->swap_readahead_info,
 			SWAP_RA_VAL(faddr, win, 0));
 
-	if (win == 1)
-		return NULL;
+	if (win == 1) {
+		pte_unmap(orig_pte);
+		return;
+	}
 
 	/* Copy the PTEs because the page table may be unmapped */
 	if (fpfn == pfn + 1)
@@ -699,23 +706,21 @@ struct page *swap_readahead_detect(struct vm_fault *vmf,
 		swap_ra_clamp_pfn(vma, faddr, fpfn - left, fpfn + win - left,
 				  &start, &end);
 	}
-	swap_ra->nr_pte = end - start;
-	swap_ra->offset = fpfn - start;
-	pte = vmf->pte - swap_ra->offset;
+	ra_info->nr_pte = end - start;
+	ra_info->offset = fpfn - start;
+	pte -= ra_info->offset;
 #ifdef CONFIG_64BIT
-	swap_ra->ptes = pte;
+	ra_info->ptes = pte;
 #else
-	tpte = swap_ra->ptes;
+	tpte = ra_info->ptes;
 	for (pfn = start; pfn != end; pfn++)
 		*tpte++ = *pte++;
 #endif
-
-	return NULL;
+	pte_unmap(orig_pte);
 }
 
 struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-				    struct vm_fault *vmf,
-				    struct vma_swap_readahead *swap_ra)
+				    struct vm_fault *vmf)
 {
 	struct blk_plug plug;
 	struct vm_area_struct *vma = vmf->vma;
@@ -724,12 +729,14 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 	swp_entry_t entry;
 	unsigned int i;
 	bool page_allocated;
+	struct vma_swap_readahead ra_info = {0,};
 
-	if (swap_ra->win == 1)
+	swap_ra_info(vmf, &ra_info);
+	if (ra_info.win == 1)
 		goto skip;
 
 	blk_start_plug(&plug);
-	for (i = 0, pte = swap_ra->ptes; i < swap_ra->nr_pte;
+	for (i = 0, pte = ra_info.ptes; i < ra_info.nr_pte;
 	     i++, pte++) {
 		pentry = *pte;
 		if (pte_none(pentry))
@@ -745,7 +752,7 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 			continue;
 		if (page_allocated) {
 			swap_readpage(page, false);
-			if (i != swap_ra->offset &&
+			if (i != ra_info.offset &&
 			    likely(!PageTransCompound(page))) {
 				SetPageReadahead(page);
 				count_vm_event(SWAP_RA);
@@ -757,7 +764,7 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 	lru_add_drain();
 skip:
 	return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address,
-				     swap_ra->win == 1);
+				     ra_info.win == 1);
 }
 
 #ifdef CONFIG_SYSFS
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH v2 1/2] mm:swap: clean up swap readahead
@ 2017-11-01  7:15   ` Minchan Kim
  0 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

When I see recent change of swap readahead, I am very unhappy
about current code structure which diverges two swap readahead
algorithm in do_swap_page. This patch is to clean it up.

Main motivation is that fault handler doesn't need to be aware of
readahead algorithms but just should call swapin_readahead.

As first step, this patch cleans up a little bit but not perfect
(I just separate for review easier) so next patch will make the goal
complete.

Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/swap.h | 17 ++--------
 mm/memory.c          | 17 +++-------
 mm/swap_state.c      | 89 ++++++++++++++++++++++++++++------------------------
 3 files changed, 55 insertions(+), 68 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 84255b3da7c1..7c7c8b344bc9 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -427,12 +427,8 @@ extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
 			bool *new_page_allocated);
 extern struct page *swapin_readahead(swp_entry_t, gfp_t,
 			struct vm_area_struct *vma, unsigned long addr);
-
-extern struct page *swap_readahead_detect(struct vm_fault *vmf,
-					  struct vma_swap_readahead *swap_ra);
 extern struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-					   struct vm_fault *vmf,
-					   struct vma_swap_readahead *swap_ra);
+					   struct vm_fault *vmf);
 
 /* linux/mm/swapfile.c */
 extern atomic_long_t nr_swap_pages;
@@ -551,15 +547,8 @@ static inline bool swap_use_vma_readahead(void)
 	return false;
 }
 
-static inline struct page *swap_readahead_detect(
-	struct vm_fault *vmf, struct vma_swap_readahead *swap_ra)
-{
-	return NULL;
-}
-
-static inline struct page *do_swap_page_readahead(
-	swp_entry_t fentry, gfp_t gfp_mask,
-	struct vm_fault *vmf, struct vma_swap_readahead *swap_ra)
+static inline struct page *do_swap_page_readahead(swp_entry_t fentry,
+				gfp_t gfp_mask, struct vm_fault *vmf)
 {
 	return NULL;
 }
diff --git a/mm/memory.c b/mm/memory.c
index 8a0c410037d2..e955298e4290 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2849,21 +2849,14 @@ int do_swap_page(struct vm_fault *vmf)
 	struct vm_area_struct *vma = vmf->vma;
 	struct page *page = NULL, *swapcache = NULL;
 	struct mem_cgroup *memcg;
-	struct vma_swap_readahead swap_ra;
 	swp_entry_t entry;
 	pte_t pte;
 	int locked;
 	int exclusive = 0;
 	int ret = 0;
-	bool vma_readahead = swap_use_vma_readahead();
 
-	if (vma_readahead)
-		page = swap_readahead_detect(vmf, &swap_ra);
-	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte)) {
-		if (page)
-			put_page(page);
+	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
 		goto out;
-	}
 
 	entry = pte_to_swp_entry(vmf->orig_pte);
 	if (unlikely(non_swap_entry(entry))) {
@@ -2889,9 +2882,7 @@ int do_swap_page(struct vm_fault *vmf)
 
 
 	delayacct_set_flag(DELAYACCT_PF_SWAPIN);
-	if (!page)
-		page = lookup_swap_cache(entry, vma_readahead ? vma : NULL,
-					 vmf->address);
+	page = lookup_swap_cache(entry, vma, vmf->address);
 	if (!page) {
 		struct swap_info_struct *si = swp_swap_info(entry);
 
@@ -2907,9 +2898,9 @@ int do_swap_page(struct vm_fault *vmf)
 				swap_readpage(page, true);
 			}
 		} else {
-			if (vma_readahead)
+			if (swap_use_vma_readahead())
 				page = do_swap_page_readahead(entry,
-					GFP_HIGHUSER_MOVABLE, vmf, &swap_ra);
+					GFP_HIGHUSER_MOVABLE, vmf);
 			else
 				page = swapin_readahead(entry,
 				       GFP_HIGHUSER_MOVABLE, vma, vmf->address);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 6c017ced11e6..e3c535fcd2df 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -331,32 +331,38 @@ struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma,
 			       unsigned long addr)
 {
 	struct page *page;
-	unsigned long ra_info;
-	int win, hits, readahead;
 
 	page = find_get_page(swap_address_space(entry), swp_offset(entry));
 
 	INC_CACHE_INFO(find_total);
 	if (page) {
+		bool vma_ra = swap_use_vma_readahead();
+		bool readahead = TestClearPageReadahead(page);
+
 		INC_CACHE_INFO(find_success);
 		if (unlikely(PageTransCompound(page)))
 			return page;
-		readahead = TestClearPageReadahead(page);
-		if (vma) {
-			ra_info = GET_SWAP_RA_VAL(vma);
-			win = SWAP_RA_WIN(ra_info);
-			hits = SWAP_RA_HITS(ra_info);
+
+		if (vma && vma_ra) {
+			unsigned long ra_val;
+			int win, hits;
+
+			ra_val = GET_SWAP_RA_VAL(vma);
+			win = SWAP_RA_WIN(ra_val);
+			hits = SWAP_RA_HITS(ra_val);
 			if (readahead)
 				hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX);
 			atomic_long_set(&vma->swap_readahead_info,
 					SWAP_RA_VAL(addr, win, hits));
 		}
+
 		if (readahead) {
 			count_vm_event(SWAP_RA_HIT);
-			if (!vma)
+			if (!vma || !vma_ra)
 				atomic_inc(&swapin_readahead_hits);
 		}
 	}
+
 	return page;
 }
 
@@ -645,16 +651,15 @@ static inline void swap_ra_clamp_pfn(struct vm_area_struct *vma,
 		    PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE));
 }
 
-struct page *swap_readahead_detect(struct vm_fault *vmf,
-				   struct vma_swap_readahead *swap_ra)
+static void swap_ra_info(struct vm_fault *vmf,
+			struct vma_swap_readahead *ra_info)
 {
 	struct vm_area_struct *vma = vmf->vma;
-	unsigned long swap_ra_info;
-	struct page *page;
+	unsigned long ra_val;
 	swp_entry_t entry;
 	unsigned long faddr, pfn, fpfn;
 	unsigned long start, end;
-	pte_t *pte;
+	pte_t *pte, *orig_pte;
 	unsigned int max_win, hits, prev_win, win, left;
 #ifndef CONFIG_64BIT
 	pte_t *tpte;
@@ -663,30 +668,32 @@ struct page *swap_readahead_detect(struct vm_fault *vmf,
 	max_win = 1 << min_t(unsigned int, READ_ONCE(page_cluster),
 			     SWAP_RA_ORDER_CEILING);
 	if (max_win == 1) {
-		swap_ra->win = 1;
-		return NULL;
+		ra_info->win = 1;
+		return;
 	}
 
 	faddr = vmf->address;
-	entry = pte_to_swp_entry(vmf->orig_pte);
-	if ((unlikely(non_swap_entry(entry))))
-		return NULL;
-	page = lookup_swap_cache(entry, vma, faddr);
-	if (page)
-		return page;
+	orig_pte = pte = pte_offset_map(vmf->pmd, faddr);
+	entry = pte_to_swp_entry(*pte);
+	if ((unlikely(non_swap_entry(entry)))) {
+		pte_unmap(orig_pte);
+		return;
+	}
 
 	fpfn = PFN_DOWN(faddr);
-	swap_ra_info = GET_SWAP_RA_VAL(vma);
-	pfn = PFN_DOWN(SWAP_RA_ADDR(swap_ra_info));
-	prev_win = SWAP_RA_WIN(swap_ra_info);
-	hits = SWAP_RA_HITS(swap_ra_info);
-	swap_ra->win = win = __swapin_nr_pages(pfn, fpfn, hits,
+	ra_val = GET_SWAP_RA_VAL(vma);
+	pfn = PFN_DOWN(SWAP_RA_ADDR(ra_val));
+	prev_win = SWAP_RA_WIN(ra_val);
+	hits = SWAP_RA_HITS(ra_val);
+	ra_info->win = win = __swapin_nr_pages(pfn, fpfn, hits,
 					       max_win, prev_win);
 	atomic_long_set(&vma->swap_readahead_info,
 			SWAP_RA_VAL(faddr, win, 0));
 
-	if (win == 1)
-		return NULL;
+	if (win == 1) {
+		pte_unmap(orig_pte);
+		return;
+	}
 
 	/* Copy the PTEs because the page table may be unmapped */
 	if (fpfn == pfn + 1)
@@ -699,23 +706,21 @@ struct page *swap_readahead_detect(struct vm_fault *vmf,
 		swap_ra_clamp_pfn(vma, faddr, fpfn - left, fpfn + win - left,
 				  &start, &end);
 	}
-	swap_ra->nr_pte = end - start;
-	swap_ra->offset = fpfn - start;
-	pte = vmf->pte - swap_ra->offset;
+	ra_info->nr_pte = end - start;
+	ra_info->offset = fpfn - start;
+	pte -= ra_info->offset;
 #ifdef CONFIG_64BIT
-	swap_ra->ptes = pte;
+	ra_info->ptes = pte;
 #else
-	tpte = swap_ra->ptes;
+	tpte = ra_info->ptes;
 	for (pfn = start; pfn != end; pfn++)
 		*tpte++ = *pte++;
 #endif
-
-	return NULL;
+	pte_unmap(orig_pte);
 }
 
 struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-				    struct vm_fault *vmf,
-				    struct vma_swap_readahead *swap_ra)
+				    struct vm_fault *vmf)
 {
 	struct blk_plug plug;
 	struct vm_area_struct *vma = vmf->vma;
@@ -724,12 +729,14 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 	swp_entry_t entry;
 	unsigned int i;
 	bool page_allocated;
+	struct vma_swap_readahead ra_info = {0,};
 
-	if (swap_ra->win == 1)
+	swap_ra_info(vmf, &ra_info);
+	if (ra_info.win == 1)
 		goto skip;
 
 	blk_start_plug(&plug);
-	for (i = 0, pte = swap_ra->ptes; i < swap_ra->nr_pte;
+	for (i = 0, pte = ra_info.ptes; i < ra_info.nr_pte;
 	     i++, pte++) {
 		pentry = *pte;
 		if (pte_none(pentry))
@@ -745,7 +752,7 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 			continue;
 		if (page_allocated) {
 			swap_readpage(page, false);
-			if (i != swap_ra->offset &&
+			if (i != ra_info.offset &&
 			    likely(!PageTransCompound(page))) {
 				SetPageReadahead(page);
 				count_vm_event(SWAP_RA);
@@ -757,7 +764,7 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 	lru_add_drain();
 skip:
 	return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address,
-				     swap_ra->win == 1);
+				     ra_info.win == 1);
 }
 
 #ifdef CONFIG_SYSFS
-- 
2.7.4

--
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^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH v2 2/2] mm:swap: unify cluster-based and vma-based swap readahead
  2017-11-01  7:15 ` Minchan Kim
@ 2017-11-01  7:15   ` Minchan Kim
  -1 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

This patch makes do_swap_page no need to be aware of two different
swap readahead algorithm. Just unify cluster-based and vma-based
readahead function call.

Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/swap.h | 27 ++++++++-------------------
 mm/memory.c          | 11 ++++-------
 mm/shmem.c           |  5 ++++-
 mm/swap_state.c      | 48 +++++++++++++++++++++++++++++++++++++-----------
 4 files changed, 53 insertions(+), 38 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 7c7c8b344bc9..95fca979b1c1 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -403,7 +403,6 @@ int generic_swapfile_activate(struct swap_info_struct *, struct file *,
 #define SWAP_ADDRESS_SPACE_SHIFT	14
 #define SWAP_ADDRESS_SPACE_PAGES	(1 << SWAP_ADDRESS_SPACE_SHIFT)
 extern struct address_space *swapper_spaces[];
-extern bool swap_vma_readahead;
 #define swap_address_space(entry)			    \
 	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
 		>> SWAP_ADDRESS_SPACE_SHIFT])
@@ -425,10 +424,10 @@ extern struct page *read_swap_cache_async(swp_entry_t, gfp_t,
 extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
 			struct vm_area_struct *vma, unsigned long addr,
 			bool *new_page_allocated);
-extern struct page *swapin_readahead(swp_entry_t, gfp_t,
-			struct vm_area_struct *vma, unsigned long addr);
-extern struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-					   struct vm_fault *vmf);
+extern struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
+				struct vm_fault *vmf);
+extern struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
+				struct vm_fault *vmf);
 
 /* linux/mm/swapfile.c */
 extern atomic_long_t nr_swap_pages;
@@ -436,11 +435,6 @@ extern long total_swap_pages;
 extern atomic_t nr_rotate_swap;
 extern bool has_usable_swap(void);
 
-static inline bool swap_use_vma_readahead(void)
-{
-	return READ_ONCE(swap_vma_readahead) && !atomic_read(&nr_rotate_swap);
-}
-
 /* Swap 50% full? Release swapcache more aggressively.. */
 static inline bool vm_swap_full(void)
 {
@@ -536,19 +530,14 @@ static inline void put_swap_page(struct page *page, swp_entry_t swp)
 {
 }
 
-static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
-			struct vm_area_struct *vma, unsigned long addr)
+static inline struct page *swap_cluster_readahead(swp_entry_t entry,
+				gfp_t gfp_mask, struct vm_fault *vmf)
 {
 	return NULL;
 }
 
-static inline bool swap_use_vma_readahead(void)
-{
-	return false;
-}
-
-static inline struct page *do_swap_page_readahead(swp_entry_t fentry,
-				gfp_t gfp_mask, struct vm_fault *vmf)
+static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
+			struct vm_fault *vmf)
 {
 	return NULL;
 }
diff --git a/mm/memory.c b/mm/memory.c
index e955298e4290..ce5e3d7ccc5c 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2889,7 +2889,8 @@ int do_swap_page(struct vm_fault *vmf)
 		if (si->flags & SWP_SYNCHRONOUS_IO &&
 				__swap_count(si, entry) == 1) {
 			/* skip swapcache */
-			page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vmf->address);
+			page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma,
+							vmf->address);
 			if (page) {
 				__SetPageLocked(page);
 				__SetPageSwapBacked(page);
@@ -2898,12 +2899,8 @@ int do_swap_page(struct vm_fault *vmf)
 				swap_readpage(page, true);
 			}
 		} else {
-			if (swap_use_vma_readahead())
-				page = do_swap_page_readahead(entry,
-					GFP_HIGHUSER_MOVABLE, vmf);
-			else
-				page = swapin_readahead(entry,
-				       GFP_HIGHUSER_MOVABLE, vma, vmf->address);
+			page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
+						vmf);
 			swapcache = page;
 		}
 
diff --git a/mm/shmem.c b/mm/shmem.c
index 62dfdc097e44..d92923834d68 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1413,9 +1413,12 @@ static struct page *shmem_swapin(swp_entry_t swap, gfp_t gfp,
 {
 	struct vm_area_struct pvma;
 	struct page *page;
+	struct vm_fault vmf;
 
 	shmem_pseudo_vma_init(&pvma, info, index);
-	page = swapin_readahead(swap, gfp, &pvma, 0);
+	vmf.vma = &pvma;
+	vmf.address = 0;
+	page = swap_cluster_readahead(swap, gfp, &vmf);
 	shmem_pseudo_vma_destroy(&pvma);
 
 	return page;
diff --git a/mm/swap_state.c b/mm/swap_state.c
index e3c535fcd2df..94e01413eb43 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -37,7 +37,7 @@ static const struct address_space_operations swap_aops = {
 
 struct address_space *swapper_spaces[MAX_SWAPFILES] __read_mostly;
 static unsigned int nr_swapper_spaces[MAX_SWAPFILES] __read_mostly;
-bool swap_vma_readahead __read_mostly = true;
+bool enable_vma_readahead __read_mostly = true;
 
 #define SWAP_RA_WIN_SHIFT	(PAGE_SHIFT / 2)
 #define SWAP_RA_HITS_MASK	((1UL << SWAP_RA_WIN_SHIFT) - 1)
@@ -321,6 +321,11 @@ void free_pages_and_swap_cache(struct page **pages, int nr)
 	release_pages(pagep, nr);
 }
 
+static inline bool swap_use_vma_readahead(void)
+{
+	return READ_ONCE(enable_vma_readahead) && !atomic_read(&nr_rotate_swap);
+}
+
 /*
  * Lookup a swap entry in the swap cache. A found page will be returned
  * unlocked and with its refcount incremented - we rely on the kernel
@@ -538,11 +543,10 @@ static unsigned long swapin_nr_pages(unsigned long offset)
 }
 
 /**
- * swapin_readahead - swap in pages in hope we need them soon
+ * swap_cluster_readahead - swap in pages in hope we need them soon
  * @entry: swap entry of this memory
  * @gfp_mask: memory allocation flags
- * @vma: user vma this address belongs to
- * @addr: target address for mempolicy
+ * @vmf: fault information
  *
  * Returns the struct page for entry and addr, after queueing swapin.
  *
@@ -554,10 +558,10 @@ static unsigned long swapin_nr_pages(unsigned long offset)
  * This has been extended to use the NUMA policies from the mm triggering
  * the readahead.
  *
- * Caller must hold down_read on the vma->vm_mm if vma is not NULL.
+ * Caller must hold down_read on the vma->vm_mm if vmf->vma is not NULL.
  */
-struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
-			struct vm_area_struct *vma, unsigned long addr)
+struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
+				struct vm_fault *vmf)
 {
 	struct page *page;
 	unsigned long entry_offset = swp_offset(entry);
@@ -566,6 +570,8 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
 	unsigned long mask;
 	struct blk_plug plug;
 	bool do_poll = true, page_allocated;
+	struct vm_area_struct *vma = vmf->vma;
+	unsigned long addr = vmf->address;
 
 	mask = swapin_nr_pages(offset) - 1;
 	if (!mask)
@@ -719,7 +725,7 @@ static void swap_ra_info(struct vm_fault *vmf,
 	pte_unmap(orig_pte);
 }
 
-struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
+struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 				    struct vm_fault *vmf)
 {
 	struct blk_plug plug;
@@ -767,20 +773,40 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 				     ra_info.win == 1);
 }
 
+/**
+ * swapin_readahead - swap in pages in hope we need them soon
+ * @entry: swap entry of this memory
+ * @gfp_mask: memory allocation flags
+ * @vmf: fault information
+ *
+ * Returns the struct page for entry and addr, after queueing swapin.
+ *
+ * It's a main entry function for swap readahead. By the configuration,
+ * it will read ahead blocks by cluster-based(ie, physical disk based)
+ * or vma-based(ie, virtual address based on faulty address) readahead.
+ */
+struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
+				struct vm_fault *vmf)
+{
+	return swap_use_vma_readahead() ?
+			swap_vma_readahead(entry, gfp_mask, vmf) :
+			swap_cluster_readahead(entry, gfp_mask, vmf);
+}
+
 #ifdef CONFIG_SYSFS
 static ssize_t vma_ra_enabled_show(struct kobject *kobj,
 				     struct kobj_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%s\n", swap_vma_readahead ? "true" : "false");
+	return sprintf(buf, "%s\n", enable_vma_readahead ? "true" : "false");
 }
 static ssize_t vma_ra_enabled_store(struct kobject *kobj,
 				      struct kobj_attribute *attr,
 				      const char *buf, size_t count)
 {
 	if (!strncmp(buf, "true", 4) || !strncmp(buf, "1", 1))
-		swap_vma_readahead = true;
+		enable_vma_readahead = true;
 	else if (!strncmp(buf, "false", 5) || !strncmp(buf, "0", 1))
-		swap_vma_readahead = false;
+		enable_vma_readahead = false;
 	else
 		return -EINVAL;
 
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH v2 2/2] mm:swap: unify cluster-based and vma-based swap readahead
@ 2017-11-01  7:15   ` Minchan Kim
  0 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-11-01  7:15 UTC (permalink / raw)
  To: Andrew Morton
  Cc: linux-kernel, linux-mm, Hugh Dickins, Huang Ying, kernel-team,
	Minchan Kim

This patch makes do_swap_page no need to be aware of two different
swap readahead algorithm. Just unify cluster-based and vma-based
readahead function call.

Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/swap.h | 27 ++++++++-------------------
 mm/memory.c          | 11 ++++-------
 mm/shmem.c           |  5 ++++-
 mm/swap_state.c      | 48 +++++++++++++++++++++++++++++++++++++-----------
 4 files changed, 53 insertions(+), 38 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 7c7c8b344bc9..95fca979b1c1 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -403,7 +403,6 @@ int generic_swapfile_activate(struct swap_info_struct *, struct file *,
 #define SWAP_ADDRESS_SPACE_SHIFT	14
 #define SWAP_ADDRESS_SPACE_PAGES	(1 << SWAP_ADDRESS_SPACE_SHIFT)
 extern struct address_space *swapper_spaces[];
-extern bool swap_vma_readahead;
 #define swap_address_space(entry)			    \
 	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
 		>> SWAP_ADDRESS_SPACE_SHIFT])
@@ -425,10 +424,10 @@ extern struct page *read_swap_cache_async(swp_entry_t, gfp_t,
 extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
 			struct vm_area_struct *vma, unsigned long addr,
 			bool *new_page_allocated);
-extern struct page *swapin_readahead(swp_entry_t, gfp_t,
-			struct vm_area_struct *vma, unsigned long addr);
-extern struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
-					   struct vm_fault *vmf);
+extern struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
+				struct vm_fault *vmf);
+extern struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
+				struct vm_fault *vmf);
 
 /* linux/mm/swapfile.c */
 extern atomic_long_t nr_swap_pages;
@@ -436,11 +435,6 @@ extern long total_swap_pages;
 extern atomic_t nr_rotate_swap;
 extern bool has_usable_swap(void);
 
-static inline bool swap_use_vma_readahead(void)
-{
-	return READ_ONCE(swap_vma_readahead) && !atomic_read(&nr_rotate_swap);
-}
-
 /* Swap 50% full? Release swapcache more aggressively.. */
 static inline bool vm_swap_full(void)
 {
@@ -536,19 +530,14 @@ static inline void put_swap_page(struct page *page, swp_entry_t swp)
 {
 }
 
-static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
-			struct vm_area_struct *vma, unsigned long addr)
+static inline struct page *swap_cluster_readahead(swp_entry_t entry,
+				gfp_t gfp_mask, struct vm_fault *vmf)
 {
 	return NULL;
 }
 
-static inline bool swap_use_vma_readahead(void)
-{
-	return false;
-}
-
-static inline struct page *do_swap_page_readahead(swp_entry_t fentry,
-				gfp_t gfp_mask, struct vm_fault *vmf)
+static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
+			struct vm_fault *vmf)
 {
 	return NULL;
 }
diff --git a/mm/memory.c b/mm/memory.c
index e955298e4290..ce5e3d7ccc5c 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2889,7 +2889,8 @@ int do_swap_page(struct vm_fault *vmf)
 		if (si->flags & SWP_SYNCHRONOUS_IO &&
 				__swap_count(si, entry) == 1) {
 			/* skip swapcache */
-			page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vmf->address);
+			page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma,
+							vmf->address);
 			if (page) {
 				__SetPageLocked(page);
 				__SetPageSwapBacked(page);
@@ -2898,12 +2899,8 @@ int do_swap_page(struct vm_fault *vmf)
 				swap_readpage(page, true);
 			}
 		} else {
-			if (swap_use_vma_readahead())
-				page = do_swap_page_readahead(entry,
-					GFP_HIGHUSER_MOVABLE, vmf);
-			else
-				page = swapin_readahead(entry,
-				       GFP_HIGHUSER_MOVABLE, vma, vmf->address);
+			page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
+						vmf);
 			swapcache = page;
 		}
 
diff --git a/mm/shmem.c b/mm/shmem.c
index 62dfdc097e44..d92923834d68 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1413,9 +1413,12 @@ static struct page *shmem_swapin(swp_entry_t swap, gfp_t gfp,
 {
 	struct vm_area_struct pvma;
 	struct page *page;
+	struct vm_fault vmf;
 
 	shmem_pseudo_vma_init(&pvma, info, index);
-	page = swapin_readahead(swap, gfp, &pvma, 0);
+	vmf.vma = &pvma;
+	vmf.address = 0;
+	page = swap_cluster_readahead(swap, gfp, &vmf);
 	shmem_pseudo_vma_destroy(&pvma);
 
 	return page;
diff --git a/mm/swap_state.c b/mm/swap_state.c
index e3c535fcd2df..94e01413eb43 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -37,7 +37,7 @@ static const struct address_space_operations swap_aops = {
 
 struct address_space *swapper_spaces[MAX_SWAPFILES] __read_mostly;
 static unsigned int nr_swapper_spaces[MAX_SWAPFILES] __read_mostly;
-bool swap_vma_readahead __read_mostly = true;
+bool enable_vma_readahead __read_mostly = true;
 
 #define SWAP_RA_WIN_SHIFT	(PAGE_SHIFT / 2)
 #define SWAP_RA_HITS_MASK	((1UL << SWAP_RA_WIN_SHIFT) - 1)
@@ -321,6 +321,11 @@ void free_pages_and_swap_cache(struct page **pages, int nr)
 	release_pages(pagep, nr);
 }
 
+static inline bool swap_use_vma_readahead(void)
+{
+	return READ_ONCE(enable_vma_readahead) && !atomic_read(&nr_rotate_swap);
+}
+
 /*
  * Lookup a swap entry in the swap cache. A found page will be returned
  * unlocked and with its refcount incremented - we rely on the kernel
@@ -538,11 +543,10 @@ static unsigned long swapin_nr_pages(unsigned long offset)
 }
 
 /**
- * swapin_readahead - swap in pages in hope we need them soon
+ * swap_cluster_readahead - swap in pages in hope we need them soon
  * @entry: swap entry of this memory
  * @gfp_mask: memory allocation flags
- * @vma: user vma this address belongs to
- * @addr: target address for mempolicy
+ * @vmf: fault information
  *
  * Returns the struct page for entry and addr, after queueing swapin.
  *
@@ -554,10 +558,10 @@ static unsigned long swapin_nr_pages(unsigned long offset)
  * This has been extended to use the NUMA policies from the mm triggering
  * the readahead.
  *
- * Caller must hold down_read on the vma->vm_mm if vma is not NULL.
+ * Caller must hold down_read on the vma->vm_mm if vmf->vma is not NULL.
  */
-struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
-			struct vm_area_struct *vma, unsigned long addr)
+struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
+				struct vm_fault *vmf)
 {
 	struct page *page;
 	unsigned long entry_offset = swp_offset(entry);
@@ -566,6 +570,8 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
 	unsigned long mask;
 	struct blk_plug plug;
 	bool do_poll = true, page_allocated;
+	struct vm_area_struct *vma = vmf->vma;
+	unsigned long addr = vmf->address;
 
 	mask = swapin_nr_pages(offset) - 1;
 	if (!mask)
@@ -719,7 +725,7 @@ static void swap_ra_info(struct vm_fault *vmf,
 	pte_unmap(orig_pte);
 }
 
-struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
+struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 				    struct vm_fault *vmf)
 {
 	struct blk_plug plug;
@@ -767,20 +773,40 @@ struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
 				     ra_info.win == 1);
 }
 
+/**
+ * swapin_readahead - swap in pages in hope we need them soon
+ * @entry: swap entry of this memory
+ * @gfp_mask: memory allocation flags
+ * @vmf: fault information
+ *
+ * Returns the struct page for entry and addr, after queueing swapin.
+ *
+ * It's a main entry function for swap readahead. By the configuration,
+ * it will read ahead blocks by cluster-based(ie, physical disk based)
+ * or vma-based(ie, virtual address based on faulty address) readahead.
+ */
+struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
+				struct vm_fault *vmf)
+{
+	return swap_use_vma_readahead() ?
+			swap_vma_readahead(entry, gfp_mask, vmf) :
+			swap_cluster_readahead(entry, gfp_mask, vmf);
+}
+
 #ifdef CONFIG_SYSFS
 static ssize_t vma_ra_enabled_show(struct kobject *kobj,
 				     struct kobj_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%s\n", swap_vma_readahead ? "true" : "false");
+	return sprintf(buf, "%s\n", enable_vma_readahead ? "true" : "false");
 }
 static ssize_t vma_ra_enabled_store(struct kobject *kobj,
 				      struct kobj_attribute *attr,
 				      const char *buf, size_t count)
 {
 	if (!strncmp(buf, "true", 4) || !strncmp(buf, "1", 1))
-		swap_vma_readahead = true;
+		enable_vma_readahead = true;
 	else if (!strncmp(buf, "false", 5) || !strncmp(buf, "0", 1))
-		swap_vma_readahead = false;
+		enable_vma_readahead = false;
 	else
 		return -EINVAL;
 
-- 
2.7.4

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^ permalink raw reply related	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-11-01  7:15 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-11-01  7:15 [PATCH v2 0/2] swap readahead clean up Minchan Kim
2017-11-01  7:15 ` Minchan Kim
2017-11-01  7:15 ` [PATCH v2 1/2] mm:swap: clean up swap readahead Minchan Kim
2017-11-01  7:15   ` Minchan Kim
2017-11-01  7:15 ` [PATCH v2 2/2] mm:swap: unify cluster-based and vma-based " Minchan Kim
2017-11-01  7:15   ` Minchan Kim

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