* [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages()
2024-04-11 13:09 [PATCH 0/2] mm: " Kefeng Wang
@ 2024-04-11 13:09 ` Kefeng Wang
0 siblings, 0 replies; 7+ messages in thread
From: Kefeng Wang @ 2024-04-11 13:09 UTC (permalink / raw)
To: Andrew Morton
Cc: Matthew Wilcox (Oracle), linux-mm, linux-fsdevel, Kefeng Wang
Like copy_pte_range()/zap_pte_range(), make mm counter batch updating
in filemap_map_pages(), the 'lat_pagefault -P 1 file' test from lmbench
shows 12% improve, and the percpu_counter_add_batch() is gone from
perf flame graph.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
include/linux/mm.h | 14 ++++++++++++++
mm/filemap.c | 19 +++++++++++--------
mm/memory.c | 14 --------------
3 files changed, 25 insertions(+), 22 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 6ad440ac3706..c7dffd358088 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2655,6 +2655,20 @@ static inline int mm_counter(struct folio *folio)
return mm_counter_file(folio);
}
+static inline void init_rss_vec(int *rss)
+{
+ memset(rss, 0, sizeof(int) * NR_MM_COUNTERS);
+}
+
+static inline void add_mm_rss_vec(struct mm_struct *mm, int *rss)
+{
+ int i;
+
+ for (i = 0; i < NR_MM_COUNTERS; i++)
+ if (rss[i])
+ add_mm_counter(mm, i, rss[i]);
+}
+
static inline unsigned long get_mm_rss(struct mm_struct *mm)
{
return get_mm_counter(mm, MM_FILEPAGES) +
diff --git a/mm/filemap.c b/mm/filemap.c
index 2274e590bab4..d8b23e976a43 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3506,7 +3506,7 @@ static struct folio *next_uptodate_folio(struct xa_state *xas,
static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
struct folio *folio, unsigned long start,
unsigned long addr, unsigned int nr_pages,
- unsigned int *mmap_miss)
+ int *rss, unsigned int *mmap_miss)
{
vm_fault_t ret = 0;
struct page *page = folio_page(folio, start);
@@ -3541,7 +3541,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
skip:
if (count) {
type = set_pte_range(vmf, folio, page, count, addr);
- add_mm_counter(vmf->vma->vm_mm, type, count);
+ rss[type] += count;
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3556,7 +3556,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
if (count) {
type = set_pte_range(vmf, folio, page, count, addr);
- add_mm_counter(vmf->vma->vm_mm, type, count);
+ rss[type] += count;
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3569,7 +3569,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
struct folio *folio, unsigned long addr,
- unsigned int *mmap_miss)
+ int *rss, unsigned int *mmap_miss)
{
vm_fault_t ret = 0;
struct page *page = &folio->page;
@@ -3592,8 +3592,7 @@ static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
if (vmf->address == addr)
ret = VM_FAULT_NOPAGE;
- add_mm_counter(vmf->vma->vm_mm,
- set_pte_range(vmf, folio, page, 1, addr), 1);
+ rss[set_pte_range(vmf, folio, page, 1, addr)]++;
folio_ref_inc(folio);
return ret;
@@ -3610,6 +3609,7 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
XA_STATE(xas, &mapping->i_pages, start_pgoff);
struct folio *folio;
vm_fault_t ret = 0;
+ int rss[NR_MM_COUNTERS];
unsigned int nr_pages = 0, mmap_miss = 0, mmap_miss_saved;
rcu_read_lock();
@@ -3629,6 +3629,8 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
folio_put(folio);
goto out;
}
+
+ init_rss_vec(rss);
do {
unsigned long end;
@@ -3640,15 +3642,16 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
if (!folio_test_large(folio))
ret |= filemap_map_order0_folio(vmf,
- folio, addr, &mmap_miss);
+ folio, addr, rss, &mmap_miss);
else
ret |= filemap_map_folio_range(vmf, folio,
xas.xa_index - folio->index, addr,
- nr_pages, &mmap_miss);
+ nr_pages, rss, &mmap_miss);
folio_unlock(folio);
folio_put(folio);
} while ((folio = next_uptodate_folio(&xas, mapping, end_pgoff)) != NULL);
+ add_mm_rss_vec(vma->vm_mm, rss);
pte_unmap_unlock(vmf->pte, vmf->ptl);
out:
rcu_read_unlock();
diff --git a/mm/memory.c b/mm/memory.c
index 485ffec9d4c7..149208da1652 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -465,20 +465,6 @@ int __pte_alloc_kernel(pmd_t *pmd)
return 0;
}
-static inline void init_rss_vec(int *rss)
-{
- memset(rss, 0, sizeof(int) * NR_MM_COUNTERS);
-}
-
-static inline void add_mm_rss_vec(struct mm_struct *mm, int *rss)
-{
- int i;
-
- for (i = 0; i < NR_MM_COUNTERS; i++)
- if (rss[i])
- add_mm_counter(mm, i, rss[i]);
-}
-
/*
* This function is called to print an error when a bad pte
* is found. For example, we might have a PFN-mapped pte in
--
2.41.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH 1/2] mm: move mm counter updating out of set_pte_range()
2024-04-12 2:57 ` [PATCH 1/2] mm: move mm counter updating out of set_pte_range() Kefeng Wang
@ 2024-04-12 2:33 ` Kefeng Wang
0 siblings, 0 replies; 7+ messages in thread
From: Kefeng Wang @ 2024-04-12 2:33 UTC (permalink / raw)
To: Andrew Morton; +Cc: Matthew Wilcox (Oracle), linux-mm, linux-fsdevel
On 2024/4/12 10:57, Kefeng Wang wrote:
> In order to support batch mm counter updating in filemap_map_pages(),
> move mm counter updating out of set_pte_range(), the folios are file
> from filemap, and distinguish folios type by vmf->flags and vma->vm_flags
> from another caller finish_fault().
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
> mm/filemap.c | 4 ++++
> mm/memory.c | 8 +++++---
> 2 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 92e2d43e4c9d..04b813f0146c 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -3540,6 +3540,8 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
> skip:
> if (count) {
> set_pte_range(vmf, folio, page, count, addr);
> + add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio),
> + count);
> folio_ref_add(folio, count);
> if (in_range(vmf->address, addr, count * PAGE_SIZE))
> ret = VM_FAULT_NOPAGE;
> @@ -3554,6 +3556,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
>
> if (count) {
> set_pte_range(vmf, folio, page, count, addr);
> + add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), count);
> folio_ref_add(folio, count);
> if (in_range(vmf->address, addr, count * PAGE_SIZE))
> ret = VM_FAULT_NOPAGE;
> @@ -3590,6 +3593,7 @@ static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
> ret = VM_FAULT_NOPAGE;
>
> set_pte_range(vmf, folio, page, 1, addr);
> + add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), 1);
> folio_ref_inc(folio);
>
> return ret;
> diff --git a/mm/memory.c b/mm/memory.c
> index 78422d1c7381..69bc63a5d6c8 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -4685,12 +4685,10 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio,
> entry = pte_mkuffd_wp(entry);
> /* copy-on-write page */
> if (write && !(vma->vm_flags & VM_SHARED)) {
> - add_mm_counter(vma->vm_mm, MM_ANONPAGES, nr);
> VM_BUG_ON_FOLIO(nr != 1, folio);
> folio_add_new_anon_rmap(folio, vma, addr);
> folio_add_lru_vma(folio, vma);
> } else {
> - add_mm_counter(vma->vm_mm, mm_counter_file(folio), nr);
> folio_add_file_rmap_ptes(folio, page, nr, vma);
> }
> set_ptes(vma->vm_mm, addr, vmf->pte, entry, nr);
> @@ -4727,9 +4725,11 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
> struct vm_area_struct *vma = vmf->vma;
> struct page *page;
> vm_fault_t ret;
> + int is_cow = (vmf->flags & FAULT_FLAG_WRITE) &&
> + !(vma->vm_flags & VM_SHARED);
oops, bool is enough.
>
> /* Did we COW the page? */
> - if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED))
> + if (is_cow)
> page = vmf->cow_page;
> else
> page = vmf->page;
> @@ -4765,8 +4765,10 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
> /* Re-check under ptl */
> if (likely(!vmf_pte_changed(vmf))) {
> struct folio *folio = page_folio(page);
> + int type = is_cow ? MM_ANONPAGES : mm_counter_file(folio);
>
> set_pte_range(vmf, folio, page, 1, vmf->address);
> + add_mm_counter(vma->vm_mm, type, 1);
> ret = 0;
> } else {
> update_mmu_tlb(vma, vmf->address, vmf->pte);
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 0/2] mm: batch mm counter updating in filemap_map_pages()
@ 2024-04-12 2:57 Kefeng Wang
2024-04-12 2:57 ` [PATCH 1/2] mm: move mm counter updating out of set_pte_range() Kefeng Wang
2024-04-12 2:57 ` [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages() Kefeng Wang
0 siblings, 2 replies; 7+ messages in thread
From: Kefeng Wang @ 2024-04-12 2:57 UTC (permalink / raw)
To: Andrew Morton
Cc: Matthew Wilcox (Oracle), linux-mm, linux-fsdevel, Kefeng Wang
Let's batch mm counter updating to accelerate filemap_map_pages().
v2:
- estimate folio type from caller and no need to return from
set_pte_range()
- use unsigned long for rss
Kefeng Wang (2):
mm: move mm counter updating out of set_pte_range()
mm: filemap: batch mm counter updating in filemap_map_pages()
mm/filemap.c | 14 ++++++++++----
mm/memory.c | 8 +++++---
2 files changed, 15 insertions(+), 7 deletions(-)
--
2.41.0
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 1/2] mm: move mm counter updating out of set_pte_range()
2024-04-12 2:57 [PATCH v2 0/2] mm: batch mm counter updating in filemap_map_pages() Kefeng Wang
@ 2024-04-12 2:57 ` Kefeng Wang
2024-04-12 2:33 ` Kefeng Wang
2024-04-12 2:57 ` [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages() Kefeng Wang
1 sibling, 1 reply; 7+ messages in thread
From: Kefeng Wang @ 2024-04-12 2:57 UTC (permalink / raw)
To: Andrew Morton
Cc: Matthew Wilcox (Oracle), linux-mm, linux-fsdevel, Kefeng Wang
In order to support batch mm counter updating in filemap_map_pages(),
move mm counter updating out of set_pte_range(), the folios are file
from filemap, and distinguish folios type by vmf->flags and vma->vm_flags
from another caller finish_fault().
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
mm/filemap.c | 4 ++++
mm/memory.c | 8 +++++---
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 92e2d43e4c9d..04b813f0146c 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3540,6 +3540,8 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
skip:
if (count) {
set_pte_range(vmf, folio, page, count, addr);
+ add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio),
+ count);
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3554,6 +3556,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
if (count) {
set_pte_range(vmf, folio, page, count, addr);
+ add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), count);
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3590,6 +3593,7 @@ static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
ret = VM_FAULT_NOPAGE;
set_pte_range(vmf, folio, page, 1, addr);
+ add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), 1);
folio_ref_inc(folio);
return ret;
diff --git a/mm/memory.c b/mm/memory.c
index 78422d1c7381..69bc63a5d6c8 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4685,12 +4685,10 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio,
entry = pte_mkuffd_wp(entry);
/* copy-on-write page */
if (write && !(vma->vm_flags & VM_SHARED)) {
- add_mm_counter(vma->vm_mm, MM_ANONPAGES, nr);
VM_BUG_ON_FOLIO(nr != 1, folio);
folio_add_new_anon_rmap(folio, vma, addr);
folio_add_lru_vma(folio, vma);
} else {
- add_mm_counter(vma->vm_mm, mm_counter_file(folio), nr);
folio_add_file_rmap_ptes(folio, page, nr, vma);
}
set_ptes(vma->vm_mm, addr, vmf->pte, entry, nr);
@@ -4727,9 +4725,11 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
struct vm_area_struct *vma = vmf->vma;
struct page *page;
vm_fault_t ret;
+ int is_cow = (vmf->flags & FAULT_FLAG_WRITE) &&
+ !(vma->vm_flags & VM_SHARED);
/* Did we COW the page? */
- if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED))
+ if (is_cow)
page = vmf->cow_page;
else
page = vmf->page;
@@ -4765,8 +4765,10 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
/* Re-check under ptl */
if (likely(!vmf_pte_changed(vmf))) {
struct folio *folio = page_folio(page);
+ int type = is_cow ? MM_ANONPAGES : mm_counter_file(folio);
set_pte_range(vmf, folio, page, 1, vmf->address);
+ add_mm_counter(vma->vm_mm, type, 1);
ret = 0;
} else {
update_mmu_tlb(vma, vmf->address, vmf->pte);
--
2.41.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages()
2024-04-12 2:57 [PATCH v2 0/2] mm: batch mm counter updating in filemap_map_pages() Kefeng Wang
2024-04-12 2:57 ` [PATCH 1/2] mm: move mm counter updating out of set_pte_range() Kefeng Wang
@ 2024-04-12 2:57 ` Kefeng Wang
2024-04-12 3:17 ` Matthew Wilcox
1 sibling, 1 reply; 7+ messages in thread
From: Kefeng Wang @ 2024-04-12 2:57 UTC (permalink / raw)
To: Andrew Morton
Cc: Matthew Wilcox (Oracle), linux-mm, linux-fsdevel, Kefeng Wang
Like copy_pte_range()/zap_pte_range(), make mm counter batch updating
in filemap_map_pages(), the 'lat_pagefault -P 1 file' test from lmbench
shows 12% improvement, and the percpu_counter_add_batch() is gone from
perf flame graph.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
mm/filemap.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 04b813f0146c..c8d41ab5034b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3506,7 +3506,7 @@ static struct folio *next_uptodate_folio(struct xa_state *xas,
static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
struct folio *folio, unsigned long start,
unsigned long addr, unsigned int nr_pages,
- unsigned int *mmap_miss)
+ unsigned long *rss, unsigned int *mmap_miss)
{
vm_fault_t ret = 0;
struct page *page = folio_page(folio, start);
@@ -3540,8 +3540,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
skip:
if (count) {
set_pte_range(vmf, folio, page, count, addr);
- add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio),
- count);
+ *rss += count;
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3556,7 +3555,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
if (count) {
set_pte_range(vmf, folio, page, count, addr);
- add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), count);
+ *rss += count;
folio_ref_add(folio, count);
if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
@@ -3569,7 +3568,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
struct folio *folio, unsigned long addr,
- unsigned int *mmap_miss)
+ unsigned long *rss, unsigned int *mmap_miss)
{
vm_fault_t ret = 0;
struct page *page = &folio->page;
@@ -3593,7 +3592,7 @@ static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
ret = VM_FAULT_NOPAGE;
set_pte_range(vmf, folio, page, 1, addr);
- add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), 1);
+ (*rss)++;
folio_ref_inc(folio);
return ret;
@@ -3610,6 +3609,7 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
XA_STATE(xas, &mapping->i_pages, start_pgoff);
struct folio *folio;
vm_fault_t ret = 0;
+ unsigned long rss = 0;
unsigned int nr_pages = 0, mmap_miss = 0, mmap_miss_saved;
rcu_read_lock();
@@ -3640,15 +3640,17 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
if (!folio_test_large(folio))
ret |= filemap_map_order0_folio(vmf,
- folio, addr, &mmap_miss);
+ folio, addr, &rss, &mmap_miss);
else
ret |= filemap_map_folio_range(vmf, folio,
xas.xa_index - folio->index, addr,
- nr_pages, &mmap_miss);
+ nr_pages, &rss, &mmap_miss);
folio_unlock(folio);
folio_put(folio);
} while ((folio = next_uptodate_folio(&xas, mapping, end_pgoff)) != NULL);
+
+ add_mm_counter(vma->vm_mm, mm_counter_file(folio), rss);
pte_unmap_unlock(vmf->pte, vmf->ptl);
out:
rcu_read_unlock();
--
2.41.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages()
2024-04-12 2:57 ` [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages() Kefeng Wang
@ 2024-04-12 3:17 ` Matthew Wilcox
2024-04-12 3:49 ` Kefeng Wang
0 siblings, 1 reply; 7+ messages in thread
From: Matthew Wilcox @ 2024-04-12 3:17 UTC (permalink / raw)
To: Kefeng Wang; +Cc: Andrew Morton, linux-mm, linux-fsdevel
On Fri, Apr 12, 2024 at 10:57:04AM +0800, Kefeng Wang wrote:
> } while ((folio = next_uptodate_folio(&xas, mapping, end_pgoff)) != NULL);
> +
> + add_mm_counter(vma->vm_mm, mm_counter_file(folio), rss);
Can't folio be NULL here?
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages()
2024-04-12 3:17 ` Matthew Wilcox
@ 2024-04-12 3:49 ` Kefeng Wang
0 siblings, 0 replies; 7+ messages in thread
From: Kefeng Wang @ 2024-04-12 3:49 UTC (permalink / raw)
To: Matthew Wilcox; +Cc: Andrew Morton, linux-mm, linux-fsdevel
On 2024/4/12 11:17, Matthew Wilcox wrote:
> On Fri, Apr 12, 2024 at 10:57:04AM +0800, Kefeng Wang wrote:
>> } while ((folio = next_uptodate_folio(&xas, mapping, end_pgoff)) != NULL);
>> +
>> + add_mm_counter(vma->vm_mm, mm_counter_file(folio), rss);
>
> Can't folio be NULL here?
indeed, I need get mm counter type before while
>
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2024-04-12 3:49 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-04-12 2:57 [PATCH v2 0/2] mm: batch mm counter updating in filemap_map_pages() Kefeng Wang
2024-04-12 2:57 ` [PATCH 1/2] mm: move mm counter updating out of set_pte_range() Kefeng Wang
2024-04-12 2:33 ` Kefeng Wang
2024-04-12 2:57 ` [PATCH 2/2] mm: filemap: batch mm counter updating in filemap_map_pages() Kefeng Wang
2024-04-12 3:17 ` Matthew Wilcox
2024-04-12 3:49 ` Kefeng Wang
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