| Message ID | 20220604004004.954674-6-zokeefe@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: userspace hugepage collapse | expand |
On Fri, Jun 3, 2022 at 5:40 PM Zach O'Keefe <zokeefe@google.com> wrote: > > Add a gfp_t flags member to struct collapse_control that allows contexts > to specify their own allocation semantics. This decouples the > allocation semantics from > /sys/kernel/mm/transparent_hugepage/khugepaged/defrag. > > khugepaged updates this member for every hugepage processed, since the > sysfs setting might change at any time. > > Signed-off-by: Zach O'Keefe <zokeefe@google.com> > --- > mm/khugepaged.c | 21 +++++++++++++-------- > 1 file changed, 13 insertions(+), 8 deletions(-) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 38488d114073..ba722347bebd 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -92,6 +92,9 @@ struct collapse_control { > > /* Last target selected in khugepaged_find_target_node() */ > int last_target_node; > + > + /* gfp used for allocation and memcg charging */ > + gfp_t gfp; > }; > > /** > @@ -994,15 +997,14 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, > return true; > } > > -static int alloc_charge_hpage(struct page **hpage, struct mm_struct *mm, > +static int alloc_charge_hpage(struct mm_struct *mm, struct page **hpage, Why did you have to reverse the order of mm and hpage? It seems pointless and you could save a couple of changed lines. > struct collapse_control *cc) > { > - gfp_t gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE; > int node = khugepaged_find_target_node(cc); > > - if (!khugepaged_alloc_page(hpage, gfp, node)) > + if (!khugepaged_alloc_page(hpage, cc->gfp, node)) > return SCAN_ALLOC_HUGE_PAGE_FAIL; > - if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, gfp))) > + if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, cc->gfp))) > return SCAN_CGROUP_CHARGE_FAIL; > count_memcg_page_event(*hpage, THP_COLLAPSE_ALLOC); > return SCAN_SUCCEED; > @@ -1032,7 +1034,7 @@ static void collapse_huge_page(struct mm_struct *mm, unsigned long address, > */ > mmap_read_unlock(mm); > > - result = alloc_charge_hpage(hpage, mm, cc); > + result = alloc_charge_hpage(mm, hpage, cc); > if (result != SCAN_SUCCEED) > goto out_nolock; > > @@ -1613,7 +1615,7 @@ static void collapse_file(struct mm_struct *mm, struct file *file, > VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem); > VM_BUG_ON(start & (HPAGE_PMD_NR - 1)); > > - result = alloc_charge_hpage(hpage, mm, cc); > + result = alloc_charge_hpage(mm, hpage, cc); > if (result != SCAN_SUCCEED) > goto out; > > @@ -2037,8 +2039,7 @@ static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, > } > #else > static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, > - pgoff_t start, struct page **hpage, > - struct collapse_control *cc) > + pgoff_t start, struct collapse_control *cc) Why was the !CONFIG_SHMEM version definition changed, but CONFIG_SHMEM version was not? > { > BUILD_BUG(); > } > @@ -2121,6 +2122,9 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, > if (unlikely(khugepaged_test_exit(mm))) > goto breakouterloop; > > + /* reset gfp flags since sysfs settings might change */ > + cc->gfp = alloc_hugepage_khugepaged_gfpmask() | > + __GFP_THISNODE; > VM_BUG_ON(khugepaged_scan.address < hstart || > khugepaged_scan.address + HPAGE_PMD_SIZE > > hend); > @@ -2255,6 +2259,7 @@ static int khugepaged(void *none) > struct mm_slot *mm_slot; > struct collapse_control cc = { > .last_target_node = NUMA_NO_NODE, > + /* .gfp set later */ Seems pointless to me. > }; > > set_freezable(); > -- > 2.36.1.255.ge46751e96f-goog >
On Mon, Jun 6, 2022 at 1:59 PM Yang Shi <shy828301@gmail.com> wrote: > > On Fri, Jun 3, 2022 at 5:40 PM Zach O'Keefe <zokeefe@google.com> wrote: > > > > Add a gfp_t flags member to struct collapse_control that allows contexts > > to specify their own allocation semantics. This decouples the > > allocation semantics from > > /sys/kernel/mm/transparent_hugepage/khugepaged/defrag. > > > > khugepaged updates this member for every hugepage processed, since the > > sysfs setting might change at any time. > > > > Signed-off-by: Zach O'Keefe <zokeefe@google.com> > > --- > > mm/khugepaged.c | 21 +++++++++++++-------- > > 1 file changed, 13 insertions(+), 8 deletions(-) > > > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > > index 38488d114073..ba722347bebd 100644 > > --- a/mm/khugepaged.c > > +++ b/mm/khugepaged.c > > @@ -92,6 +92,9 @@ struct collapse_control { > > > > /* Last target selected in khugepaged_find_target_node() */ > > int last_target_node; > > + > > + /* gfp used for allocation and memcg charging */ > > + gfp_t gfp; > > }; > > > > /** > > @@ -994,15 +997,14 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, > > return true; > > } > > > > -static int alloc_charge_hpage(struct page **hpage, struct mm_struct *mm, > > +static int alloc_charge_hpage(struct mm_struct *mm, struct page **hpage, > > Why did you have to reverse the order of mm and hpage? It seems > pointless and you could save a couple of changed lines. At some point many versions ago I must have thought it was cleaner to be consistent with struct *mm as 1st arg, but agree with unnecessary change and have removed. > > struct collapse_control *cc) > > { > > - gfp_t gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE; > > int node = khugepaged_find_target_node(cc); > > > > - if (!khugepaged_alloc_page(hpage, gfp, node)) > > + if (!khugepaged_alloc_page(hpage, cc->gfp, node)) > > return SCAN_ALLOC_HUGE_PAGE_FAIL; > > - if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, gfp))) > > + if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, cc->gfp))) > > return SCAN_CGROUP_CHARGE_FAIL; > > count_memcg_page_event(*hpage, THP_COLLAPSE_ALLOC); > > return SCAN_SUCCEED; > > @@ -1032,7 +1034,7 @@ static void collapse_huge_page(struct mm_struct *mm, unsigned long address, > > */ > > mmap_read_unlock(mm); > > > > - result = alloc_charge_hpage(hpage, mm, cc); > > + result = alloc_charge_hpage(mm, hpage, cc); > > if (result != SCAN_SUCCEED) > > goto out_nolock; > > > > @@ -1613,7 +1615,7 @@ static void collapse_file(struct mm_struct *mm, struct file *file, > > VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem); > > VM_BUG_ON(start & (HPAGE_PMD_NR - 1)); > > > > - result = alloc_charge_hpage(hpage, mm, cc); > > + result = alloc_charge_hpage(mm, hpage, cc); > > if (result != SCAN_SUCCEED) > > goto out; > > > > @@ -2037,8 +2039,7 @@ static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, > > } > > #else > > static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, > > - pgoff_t start, struct page **hpage, > > - struct collapse_control *cc) > > + pgoff_t start, struct collapse_control *cc) > > Why was the !CONFIG_SHMEM version definition changed, but CONFIG_SHMEM > version was not? Definitely an error - sorry about that. Surprised I didn't get caught by this earlier - must be because the signatures are eventually made equal when struct **hpage is dropped. Have fixed it. > > { > > BUILD_BUG(); > > } > > @@ -2121,6 +2122,9 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, > > if (unlikely(khugepaged_test_exit(mm))) > > goto breakouterloop; > > > > + /* reset gfp flags since sysfs settings might change */ > > + cc->gfp = alloc_hugepage_khugepaged_gfpmask() | > > + __GFP_THISNODE; > > VM_BUG_ON(khugepaged_scan.address < hstart || > > khugepaged_scan.address + HPAGE_PMD_SIZE > > > hend); > > @@ -2255,6 +2259,7 @@ static int khugepaged(void *none) > > struct mm_slot *mm_slot; > > struct collapse_control cc = { > > .last_target_node = NUMA_NO_NODE, > > + /* .gfp set later */ > > Seems pointless to me. Ack. Removed. > > }; > > > > set_freezable(); > > -- > > 2.36.1.255.ge46751e96f-goog > >
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 38488d114073..ba722347bebd 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -92,6 +92,9 @@ struct collapse_control { /* Last target selected in khugepaged_find_target_node() */ int last_target_node; + + /* gfp used for allocation and memcg charging */ + gfp_t gfp; }; /** @@ -994,15 +997,14 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm, return true; } -static int alloc_charge_hpage(struct page **hpage, struct mm_struct *mm, +static int alloc_charge_hpage(struct mm_struct *mm, struct page **hpage, struct collapse_control *cc) { - gfp_t gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE; int node = khugepaged_find_target_node(cc); - if (!khugepaged_alloc_page(hpage, gfp, node)) + if (!khugepaged_alloc_page(hpage, cc->gfp, node)) return SCAN_ALLOC_HUGE_PAGE_FAIL; - if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, gfp))) + if (unlikely(mem_cgroup_charge(page_folio(*hpage), mm, cc->gfp))) return SCAN_CGROUP_CHARGE_FAIL; count_memcg_page_event(*hpage, THP_COLLAPSE_ALLOC); return SCAN_SUCCEED; @@ -1032,7 +1034,7 @@ static void collapse_huge_page(struct mm_struct *mm, unsigned long address, */ mmap_read_unlock(mm); - result = alloc_charge_hpage(hpage, mm, cc); + result = alloc_charge_hpage(mm, hpage, cc); if (result != SCAN_SUCCEED) goto out_nolock; @@ -1613,7 +1615,7 @@ static void collapse_file(struct mm_struct *mm, struct file *file, VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem); VM_BUG_ON(start & (HPAGE_PMD_NR - 1)); - result = alloc_charge_hpage(hpage, mm, cc); + result = alloc_charge_hpage(mm, hpage, cc); if (result != SCAN_SUCCEED) goto out; @@ -2037,8 +2039,7 @@ static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, } #else static void khugepaged_scan_file(struct mm_struct *mm, struct file *file, - pgoff_t start, struct page **hpage, - struct collapse_control *cc) + pgoff_t start, struct collapse_control *cc) { BUILD_BUG(); } @@ -2121,6 +2122,9 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, if (unlikely(khugepaged_test_exit(mm))) goto breakouterloop; + /* reset gfp flags since sysfs settings might change */ + cc->gfp = alloc_hugepage_khugepaged_gfpmask() | + __GFP_THISNODE; VM_BUG_ON(khugepaged_scan.address < hstart || khugepaged_scan.address + HPAGE_PMD_SIZE > hend); @@ -2255,6 +2259,7 @@ static int khugepaged(void *none) struct mm_slot *mm_slot; struct collapse_control cc = { .last_target_node = NUMA_NO_NODE, + /* .gfp set later */ }; set_freezable();
Add a gfp_t flags member to struct collapse_control that allows contexts to specify their own allocation semantics. This decouples the allocation semantics from /sys/kernel/mm/transparent_hugepage/khugepaged/defrag. khugepaged updates this member for every hugepage processed, since the sysfs setting might change at any time. Signed-off-by: Zach O'Keefe <zokeefe@google.com> --- mm/khugepaged.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-)