| Message ID | 20240118123911.88833-8-gang.li@linux.dev (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | hugetlb: parallelize hugetlb page init on boot | expand |
On 2024/1/18 20:39, Gang Li wrote: > Optimizing the initialization speed of 1G huge pages through > parallelization. > > 1G hugetlbs are allocated from bootmem, a process that is already > very fast and does not currently require optimization. Therefore, > we focus on parallelizing only the initialization phase in > `gather_bootmem_prealloc`. > > Here are some test results: > test no patch(ms) patched(ms) saved > ------------------- -------------- ------------- -------- > 256c2t(4 node) 1G 4745 2024 57.34% > 128c1t(2 node) 1G 3358 1712 49.02% > 12t 1G 77000 18300 76.23% > > Signed-off-by: Gang Li <gang.li@linux.dev> > Tested-by: David Rientjes <rientjes@google.com> > --- > include/linux/hugetlb.h | 2 +- > mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- > 2 files changed, 35 insertions(+), 9 deletions(-) > > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > index c1ee640d87b1..77b30a8c6076 100644 > --- a/include/linux/hugetlb.h > +++ b/include/linux/hugetlb.h > @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, > struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage); > > extern int sysctl_hugetlb_shm_group; > -extern struct list_head huge_boot_pages; > +extern struct list_head huge_boot_pages[MAX_NUMNODES]; Hi, please update arch/powerpc/mm/hugetlbpage.c too, since it was used in ppc. > > /* arch callbacks */ > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 9b348ba418f5..2f4b77630ada 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -69,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) > #endif > static unsigned long hugetlb_cma_size __initdata; > > -__initdata LIST_HEAD(huge_boot_pages); > +__initdata struct list_head huge_boot_pages[MAX_NUMNODES]; > > /* for command line parsing */ > static struct hstate * __initdata parsed_hstate; > @@ -3301,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, int nid) > int __alloc_bootmem_huge_page(struct hstate *h, int nid) > { > struct huge_bootmem_page *m = NULL; /* initialize for clang */ > - int nr_nodes, node; > + int nr_nodes, node = nid; > > /* do node specific alloc */ > if (nid != NUMA_NO_NODE) { > @@ -3339,7 +3339,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) > huge_page_size(h) - PAGE_SIZE); > /* Put them into a private list first because mem_map is not up yet */ > INIT_LIST_HEAD(&m->list); > - list_add(&m->list, &huge_boot_pages); > + list_add(&m->list, &huge_boot_pages[node]); > m->hstate = h; > return 1; > } > @@ -3390,8 +3390,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, > /* Send list for bulk vmemmap optimization processing */ > hugetlb_vmemmap_optimize_folios(h, folio_list); > > - /* Add all new pool pages to free lists in one lock cycle */ > - spin_lock_irqsave(&hugetlb_lock, flags); > list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { > if (!folio_test_hugetlb_vmemmap_optimized(folio)) { > /* > @@ -3404,23 +3402,27 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, > HUGETLB_VMEMMAP_RESERVE_PAGES, > pages_per_huge_page(h)); > } > + /* Subdivide locks to achieve better parallel performance */ > + spin_lock_irqsave(&hugetlb_lock, flags); > __prep_account_new_huge_page(h, folio_nid(folio)); > enqueue_hugetlb_folio(h, folio); > + spin_unlock_irqrestore(&hugetlb_lock, flags); > } > - spin_unlock_irqrestore(&hugetlb_lock, flags); > } > > /* > * Put bootmem huge pages into the standard lists after mem_map is up. > * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. > */ > -static void __init gather_bootmem_prealloc(void) > +static void __init __gather_bootmem_prealloc(unsigned long start, unsigned long end, void *arg) > + > { > + int nid = start; > LIST_HEAD(folio_list); > struct huge_bootmem_page *m; > struct hstate *h = NULL, *prev_h = NULL; > > - list_for_each_entry(m, &huge_boot_pages, list) { > + list_for_each_entry(m, &huge_boot_pages[nid], list) { > struct page *page = virt_to_page(m); > struct folio *folio = (void *)page; > > @@ -3453,6 +3455,22 @@ static void __init gather_bootmem_prealloc(void) > prep_and_add_bootmem_folios(h, &folio_list); > } > > +static void __init gather_bootmem_prealloc(void) > +{ > + struct padata_mt_job job = { > + .thread_fn = __gather_bootmem_prealloc, > + .fn_arg = NULL, > + .start = 0, > + .size = num_node_state(N_MEMORY), > + .align = 1, > + .min_chunk = 1, > + .max_threads = num_node_state(N_MEMORY), > + .numa_aware = true, > + }; > + > + padata_do_multithreaded(&job); > +} > + > static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) > { > unsigned long i; > @@ -3602,6 +3620,14 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) > return; > } > > + /* hugetlb_hstate_alloc_pages will be called many times, init huge_boot_pages once*/ > + if (huge_boot_pages[0].next == NULL) { > + int i = 0; > + > + for (i = 0; i < MAX_NUMNODES; i++) > + INIT_LIST_HEAD(&huge_boot_pages[i]); > + } > + > /* do node specific alloc */ > if (hugetlb_hstate_alloc_pages_specific_nodes(h)) > return;
On 2024/1/18 22:22, Kefeng Wang wrote: > On 2024/1/18 20:39, Gang Li wrote: >> include/linux/hugetlb.h | 2 +- >> mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- >> 2 files changed, 35 insertions(+), 9 deletions(-) >> >> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >> index c1ee640d87b1..77b30a8c6076 100644 >> --- a/include/linux/hugetlb.h >> +++ b/include/linux/hugetlb.h >> @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct >> vm_area_struct *vma, >> struct address_space *hugetlb_page_mapping_lock_write(struct page >> *hpage); >> extern int sysctl_hugetlb_shm_group; >> -extern struct list_head huge_boot_pages; >> +extern struct list_head huge_boot_pages[MAX_NUMNODES]; > > Hi, please update arch/powerpc/mm/hugetlbpage.c too, since it > was used in ppc. > Thanks, will do
On 2024/1/18 20:39, Gang Li wrote: > Optimizing the initialization speed of 1G huge pages through > parallelization. > > 1G hugetlbs are allocated from bootmem, a process that is already > very fast and does not currently require optimization. Therefore, > we focus on parallelizing only the initialization phase in > `gather_bootmem_prealloc`. > > Here are some test results: > test no patch(ms) patched(ms) saved > ------------------- -------------- ------------- -------- > 256c2t(4 node) 1G 4745 2024 57.34% What does "256c2t" mean? > 128c1t(2 node) 1G 3358 1712 49.02% > 12t 1G 77000 18300 76.23% > > Signed-off-by: Gang Li <gang.li@linux.dev> > Tested-by: David Rientjes <rientjes@google.com> > --- > include/linux/hugetlb.h | 2 +- > mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- > 2 files changed, 35 insertions(+), 9 deletions(-) > > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > index c1ee640d87b1..77b30a8c6076 100644 > --- a/include/linux/hugetlb.h > +++ b/include/linux/hugetlb.h > @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, > struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage); > > extern int sysctl_hugetlb_shm_group; > -extern struct list_head huge_boot_pages; > +extern struct list_head huge_boot_pages[MAX_NUMNODES]; > > /* arch callbacks */ > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 9b348ba418f5..2f4b77630ada 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -69,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) > #endif > static unsigned long hugetlb_cma_size __initdata; > > -__initdata LIST_HEAD(huge_boot_pages); > +__initdata struct list_head huge_boot_pages[MAX_NUMNODES]; > > /* for command line parsing */ > static struct hstate * __initdata parsed_hstate; > @@ -3301,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, int nid) > int __alloc_bootmem_huge_page(struct hstate *h, int nid) > { > struct huge_bootmem_page *m = NULL; /* initialize for clang */ > - int nr_nodes, node; > + int nr_nodes, node = nid; Why not use nid directly in the following list_add()? > > /* do node specific alloc */ > if (nid != NUMA_NO_NODE) { > @@ -3339,7 +3339,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) > huge_page_size(h) - PAGE_SIZE); > /* Put them into a private list first because mem_map is not up yet */ > INIT_LIST_HEAD(&m->list); > - list_add(&m->list, &huge_boot_pages); > + list_add(&m->list, &huge_boot_pages[node]); > m->hstate = h; > return 1; > } > @@ -3390,8 +3390,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, > /* Send list for bulk vmemmap optimization processing */ > hugetlb_vmemmap_optimize_folios(h, folio_list); > > - /* Add all new pool pages to free lists in one lock cycle */ > - spin_lock_irqsave(&hugetlb_lock, flags); > list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { > if (!folio_test_hugetlb_vmemmap_optimized(folio)) { > /* > @@ -3404,23 +3402,27 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, > HUGETLB_VMEMMAP_RESERVE_PAGES, > pages_per_huge_page(h)); > } > + /* Subdivide locks to achieve better parallel performance * > + spin_lock_irqsave(&hugetlb_lock, flags); > __prep_account_new_huge_page(h, folio_nid(folio)); > enqueue_hugetlb_folio(h, folio); > + spin_unlock_irqrestore(&hugetlb_lock, flags); > } > - spin_unlock_irqrestore(&hugetlb_lock, flags); > } > > /* > * Put bootmem huge pages into the standard lists after mem_map is up. > * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. > */ > -static void __init gather_bootmem_prealloc(void) > +static void __init __gather_bootmem_prealloc(unsigned long start, unsigned long end, void *arg) This function name could be gather_bootmem_prealloc_node. > + > { > + int nid = start; > LIST_HEAD(folio_list); > struct huge_bootmem_page *m; > struct hstate *h = NULL, *prev_h = NULL; > > - list_for_each_entry(m, &huge_boot_pages, list) { > + list_for_each_entry(m, &huge_boot_pages[nid], list) { > struct page *page = virt_to_page(m); > struct folio *folio = (void *)page; > > @@ -3453,6 +3455,22 @@ static void __init gather_bootmem_prealloc(void) > prep_and_add_bootmem_folios(h, &folio_list); > } > > +static void __init gather_bootmem_prealloc(void) > +{ > + struct padata_mt_job job = { > + .thread_fn = __gather_bootmem_prealloc, > + .fn_arg = NULL, > + .start = 0, > + .size = num_node_state(N_MEMORY), > + .align = 1, > + .min_chunk = 1, > + .max_threads = num_node_state(N_MEMORY), > + .numa_aware = true, > + }; > + > + padata_do_multithreaded(&job); > +} > + > static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) > { > unsigned long i; > @@ -3602,6 +3620,14 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) > return; > } > > + /* hugetlb_hstate_alloc_pages will be called many times, init huge_boot_pages once*/ s/init/initialize/g And you miss a black right before "*/". > + if (huge_boot_pages[0].next == NULL) { It it not intuitive. I'd like to use a 'initialied' variable to indicate whether it has been initialized. BTW, it can be marked as __initdata. > + int i = 0; > + > + for (i = 0; i < MAX_NUMNODES; i++) > + INIT_LIST_HEAD(&huge_boot_pages[i]); > + } > + > /* do node specific alloc */ > if (hugetlb_hstate_alloc_pages_specific_nodes(h)) > return;
On 2024/1/24 17:23, Muchun Song wrote: > On 2024/1/18 20:39, Gang Li wrote: >> Optimizing the initialization speed of 1G huge pages through >> parallelization. >> >> 1G hugetlbs are allocated from bootmem, a process that is already >> very fast and does not currently require optimization. Therefore, >> we focus on parallelizing only the initialization phase in >> `gather_bootmem_prealloc`. >> >> Here are some test results: >> test no patch(ms) patched(ms) saved >> ------------------- -------------- ------------- -------- >> 256c2t(4 node) 1G 4745 2024 57.34% > > What does "256c2t" mean? A machine with 256 core and 2T memory. > >> 128c1t(2 node) 1G 3358 1712 49.02% >> 12t 1G 77000 18300 76.23% >> >> Signed-off-by: Gang Li <gang.li@linux.dev> >> Tested-by: David Rientjes <rientjes@google.com> >> --- >> include/linux/hugetlb.h | 2 +- >> mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- >> 2 files changed, 35 insertions(+), 9 deletions(-) >> >> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >> index c1ee640d87b1..77b30a8c6076 100644 >> --- a/include/linux/hugetlb.h >> +++ b/include/linux/hugetlb.h >> @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct >> vm_area_struct *vma, >> struct address_space *hugetlb_page_mapping_lock_write(struct page >> *hpage); >> extern int sysctl_hugetlb_shm_group; >> -extern struct list_head huge_boot_pages; >> +extern struct list_head huge_boot_pages[MAX_NUMNODES]; >> /* arch callbacks */ >> diff --git a/mm/hugetlb.c b/mm/hugetlb.c >> index 9b348ba418f5..2f4b77630ada 100644 >> --- a/mm/hugetlb.c >> +++ b/mm/hugetlb.c >> @@ -69,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, >> unsigned int order) >> #endif >> static unsigned long hugetlb_cma_size __initdata; >> -__initdata LIST_HEAD(huge_boot_pages); >> +__initdata struct list_head huge_boot_pages[MAX_NUMNODES]; >> /* for command line parsing */ >> static struct hstate * __initdata parsed_hstate; >> @@ -3301,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, >> int nid) >> int __alloc_bootmem_huge_page(struct hstate *h, int nid) >> { >> struct huge_bootmem_page *m = NULL; /* initialize for clang */ >> - int nr_nodes, node; >> + int nr_nodes, node = nid; > > Why not use nid directly in the following list_add()? `node` may be changed in `for_each_node_mask_to_alloc`. > >> /* do node specific alloc */ >> if (nid != NUMA_NO_NODE) { >> @@ -3339,7 +3339,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, >> int nid) >> huge_page_size(h) - PAGE_SIZE); >> /* Put them into a private list first because mem_map is not up >> yet */ >> INIT_LIST_HEAD(&m->list); >> - list_add(&m->list, &huge_boot_pages); >> + list_add(&m->list, &huge_boot_pages[node]); >> m->hstate = h; >> return 1; >> } >> @@ -3390,8 +3390,6 @@ static void __init >> prep_and_add_bootmem_folios(struct hstate *h, >> /* Send list for bulk vmemmap optimization processing */ >> hugetlb_vmemmap_optimize_folios(h, folio_list); >> - /* Add all new pool pages to free lists in one lock cycle */ >> - spin_lock_irqsave(&hugetlb_lock, flags); >> list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { >> if (!folio_test_hugetlb_vmemmap_optimized(folio)) { >> /* >> @@ -3404,23 +3402,27 @@ static void __init >> prep_and_add_bootmem_folios(struct hstate *h, >> HUGETLB_VMEMMAP_RESERVE_PAGES, >> pages_per_huge_page(h)); >> } >> + /* Subdivide locks to achieve better parallel performance * >> + spin_lock_irqsave(&hugetlb_lock, flags); >> __prep_account_new_huge_page(h, folio_nid(folio)); >> enqueue_hugetlb_folio(h, folio); >> + spin_unlock_irqrestore(&hugetlb_lock, flags); >> } >> - spin_unlock_irqrestore(&hugetlb_lock, flags); >> } >> /* >> * Put bootmem huge pages into the standard lists after mem_map is up. >> * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. >> */ >> -static void __init gather_bootmem_prealloc(void) >> +static void __init __gather_bootmem_prealloc(unsigned long start, >> unsigned long end, void *arg) > > This function name could be gather_bootmem_prealloc_node. > LGTM. >> + >> { >> + int nid = start; >> LIST_HEAD(folio_list); >> struct huge_bootmem_page *m; >> struct hstate *h = NULL, *prev_h = NULL; >> - list_for_each_entry(m, &huge_boot_pages, list) { >> + list_for_each_entry(m, &huge_boot_pages[nid], list) { >> struct page *page = virt_to_page(m); >> struct folio *folio = (void *)page; >> @@ -3453,6 +3455,22 @@ static void __init gather_bootmem_prealloc(void) >> prep_and_add_bootmem_folios(h, &folio_list); >> } >> +static void __init gather_bootmem_prealloc(void) >> +{ >> + struct padata_mt_job job = { >> + .thread_fn = __gather_bootmem_prealloc, >> + .fn_arg = NULL, >> + .start = 0, >> + .size = num_node_state(N_MEMORY), >> + .align = 1, >> + .min_chunk = 1, >> + .max_threads = num_node_state(N_MEMORY), >> + .numa_aware = true, >> + }; >> + >> + padata_do_multithreaded(&job); >> +} >> + >> static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate >> *h, int nid) >> { >> unsigned long i; >> @@ -3602,6 +3620,14 @@ static void __init >> hugetlb_hstate_alloc_pages(struct hstate *h) >> return; >> } >> + /* hugetlb_hstate_alloc_pages will be called many times, init >> huge_boot_pages once*/ > > s/init/initialize/g > > And you miss a black right before "*/". OK > >> + if (huge_boot_pages[0].next == NULL) { > > It it not intuitive. I'd like to use a 'initialied' variable Would it make the code look a bit redundant? > to indicate whether it has been initialized. BTW, it can be > marked as __initdata. > OK
> On Jan 24, 2024, at 18:52, Gang Li <gang.li@linux.dev> wrote: > > On 2024/1/24 17:23, Muchun Song wrote: >> On 2024/1/18 20:39, Gang Li wrote: >>> Optimizing the initialization speed of 1G huge pages through >>> parallelization. >>> >>> 1G hugetlbs are allocated from bootmem, a process that is already >>> very fast and does not currently require optimization. Therefore, >>> we focus on parallelizing only the initialization phase in >>> `gather_bootmem_prealloc`. >>> >>> Here are some test results: >>> test no patch(ms) patched(ms) saved >>> ------------------- -------------- ------------- -------- >>> 256c2t(4 node) 1G 4745 2024 57.34% >> What does "256c2t" mean? > > A machine with 256 core and 2T memory. A little confusing. I thought 256c2 is a number in hexadecimal. The unit of memory should be capital T. We should add a simple explanation about this. > >>> 128c1t(2 node) 1G 3358 1712 49.02% >>> 12t 1G 77000 18300 76.23% I am curious how many NUMA nodes does this system have? I suspect it should not be one. >>> >>> Signed-off-by: Gang Li <gang.li@linux.dev> >>> Tested-by: David Rientjes <rientjes@google.com> >>> --- >>> include/linux/hugetlb.h | 2 +- >>> mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- >>> 2 files changed, 35 insertions(+), 9 deletions(-) >>> >>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >>> index c1ee640d87b1..77b30a8c6076 100644 >>> --- a/include/linux/hugetlb.h >>> +++ b/include/linux/hugetlb.h >>> @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, >>> struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage); >>> extern int sysctl_hugetlb_shm_group; >>> -extern struct list_head huge_boot_pages; >>> +extern struct list_head huge_boot_pages[MAX_NUMNODES]; >>> /* arch callbacks */ >>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c >>> index 9b348ba418f5..2f4b77630ada 100644 >>> --- a/mm/hugetlb.c >>> +++ b/mm/hugetlb.c >>> @@ -69,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) >>> #endif >>> static unsigned long hugetlb_cma_size __initdata; >>> -__initdata LIST_HEAD(huge_boot_pages); >>> +__initdata struct list_head huge_boot_pages[MAX_NUMNODES]; >>> /* for command line parsing */ >>> static struct hstate * __initdata parsed_hstate; >>> @@ -3301,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, int nid) >>> int __alloc_bootmem_huge_page(struct hstate *h, int nid) >>> { >>> struct huge_bootmem_page *m = NULL; /* initialize for clang */ >>> - int nr_nodes, node; >>> + int nr_nodes, node = nid; >> Why not use nid directly in the following list_add()? > > `node` may be changed in `for_each_node_mask_to_alloc`. Got it. > >>> /* do node specific alloc */ >>> if (nid != NUMA_NO_NODE) { >>> @@ -3339,7 +3339,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) >>> huge_page_size(h) - PAGE_SIZE); >>> /* Put them into a private list first because mem_map is not up yet */ >>> INIT_LIST_HEAD(&m->list); >>> - list_add(&m->list, &huge_boot_pages); >>> + list_add(&m->list, &huge_boot_pages[node]); >>> m->hstate = h; >>> return 1; >>> } >>> @@ -3390,8 +3390,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, >>> /* Send list for bulk vmemmap optimization processing */ >>> hugetlb_vmemmap_optimize_folios(h, folio_list); >>> - /* Add all new pool pages to free lists in one lock cycle */ >>> - spin_lock_irqsave(&hugetlb_lock, flags); >>> list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { >>> if (!folio_test_hugetlb_vmemmap_optimized(folio)) { >>> /* >>> @@ -3404,23 +3402,27 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, >>> HUGETLB_VMEMMAP_RESERVE_PAGES, >>> pages_per_huge_page(h)); >>> } >>> + /* Subdivide locks to achieve better parallel performance * >>> + spin_lock_irqsave(&hugetlb_lock, flags); >>> __prep_account_new_huge_page(h, folio_nid(folio)); >>> enqueue_hugetlb_folio(h, folio); >>> + spin_unlock_irqrestore(&hugetlb_lock, flags); >>> } >>> - spin_unlock_irqrestore(&hugetlb_lock, flags); >>> } >>> /* >>> * Put bootmem huge pages into the standard lists after mem_map is up. >>> * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. >>> */ >>> -static void __init gather_bootmem_prealloc(void) >>> +static void __init __gather_bootmem_prealloc(unsigned long start, unsigned long end, void *arg) >> This function name could be gather_bootmem_prealloc_node. > > LGTM. > >>> + >>> { >>> + int nid = start; >>> LIST_HEAD(folio_list); >>> struct huge_bootmem_page *m; >>> struct hstate *h = NULL, *prev_h = NULL; >>> - list_for_each_entry(m, &huge_boot_pages, list) { >>> + list_for_each_entry(m, &huge_boot_pages[nid], list) { >>> struct page *page = virt_to_page(m); >>> struct folio *folio = (void *)page; >>> @@ -3453,6 +3455,22 @@ static void __init gather_bootmem_prealloc(void) >>> prep_and_add_bootmem_folios(h, &folio_list); >>> } >>> +static void __init gather_bootmem_prealloc(void) >>> +{ >>> + struct padata_mt_job job = { >>> + .thread_fn = __gather_bootmem_prealloc, >>> + .fn_arg = NULL, >>> + .start = 0, >>> + .size = num_node_state(N_MEMORY), >>> + .align = 1, >>> + .min_chunk = 1, >>> + .max_threads = num_node_state(N_MEMORY), >>> + .numa_aware = true, >>> + }; >>> + >>> + padata_do_multithreaded(&job); >>> +} >>> + >>> static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) >>> { >>> unsigned long i; >>> @@ -3602,6 +3620,14 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) >>> return; >>> } >>> + /* hugetlb_hstate_alloc_pages will be called many times, init huge_boot_pages once*/ >> s/init/initialize/g >> And you miss a black right before "*/". > > OK > >>> + if (huge_boot_pages[0].next == NULL) { >> It it not intuitive. I'd like to use a 'initialied' variable > > Would it make the code look a bit redundant? What is redundant? > >> to indicate whether it has been initialized. BTW, it can be >> marked as __initdata. >> > > OK
On 2024/1/25 10:48, Muchun Song wrote:>>>> 12t 1G 77000 18300 76.23% > > I am curious how many NUMA nodes does this system have? I suspect > it should not be one. > Hi David Rientjes, I'm also curious. Can you show us some details about this machine? Such as `lscpu`. Thanks!
On 2024/1/25 10:48, Muchun Song wrote: >>>> + if (huge_boot_pages[0].next == NULL) { >>> It it not intuitive. I'd like to use a 'initialied' variable >> >> Would it make the code look a bit redundant? > > What is redundant? > I was thinking of adding a global variable at first, but it's possible to add a local static variable, which is more concise.
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index c1ee640d87b1..77b30a8c6076 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -178,7 +178,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage); extern int sysctl_hugetlb_shm_group; -extern struct list_head huge_boot_pages; +extern struct list_head huge_boot_pages[MAX_NUMNODES]; /* arch callbacks */ diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 9b348ba418f5..2f4b77630ada 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -69,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, unsigned int order) #endif static unsigned long hugetlb_cma_size __initdata; -__initdata LIST_HEAD(huge_boot_pages); +__initdata struct list_head huge_boot_pages[MAX_NUMNODES]; /* for command line parsing */ static struct hstate * __initdata parsed_hstate; @@ -3301,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, int nid) int __alloc_bootmem_huge_page(struct hstate *h, int nid) { struct huge_bootmem_page *m = NULL; /* initialize for clang */ - int nr_nodes, node; + int nr_nodes, node = nid; /* do node specific alloc */ if (nid != NUMA_NO_NODE) { @@ -3339,7 +3339,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid) huge_page_size(h) - PAGE_SIZE); /* Put them into a private list first because mem_map is not up yet */ INIT_LIST_HEAD(&m->list); - list_add(&m->list, &huge_boot_pages); + list_add(&m->list, &huge_boot_pages[node]); m->hstate = h; return 1; } @@ -3390,8 +3390,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, /* Send list for bulk vmemmap optimization processing */ hugetlb_vmemmap_optimize_folios(h, folio_list); - /* Add all new pool pages to free lists in one lock cycle */ - spin_lock_irqsave(&hugetlb_lock, flags); list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { if (!folio_test_hugetlb_vmemmap_optimized(folio)) { /* @@ -3404,23 +3402,27 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h, HUGETLB_VMEMMAP_RESERVE_PAGES, pages_per_huge_page(h)); } + /* Subdivide locks to achieve better parallel performance */ + spin_lock_irqsave(&hugetlb_lock, flags); __prep_account_new_huge_page(h, folio_nid(folio)); enqueue_hugetlb_folio(h, folio); + spin_unlock_irqrestore(&hugetlb_lock, flags); } - spin_unlock_irqrestore(&hugetlb_lock, flags); } /* * Put bootmem huge pages into the standard lists after mem_map is up. * Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages. */ -static void __init gather_bootmem_prealloc(void) +static void __init __gather_bootmem_prealloc(unsigned long start, unsigned long end, void *arg) + { + int nid = start; LIST_HEAD(folio_list); struct huge_bootmem_page *m; struct hstate *h = NULL, *prev_h = NULL; - list_for_each_entry(m, &huge_boot_pages, list) { + list_for_each_entry(m, &huge_boot_pages[nid], list) { struct page *page = virt_to_page(m); struct folio *folio = (void *)page; @@ -3453,6 +3455,22 @@ static void __init gather_bootmem_prealloc(void) prep_and_add_bootmem_folios(h, &folio_list); } +static void __init gather_bootmem_prealloc(void) +{ + struct padata_mt_job job = { + .thread_fn = __gather_bootmem_prealloc, + .fn_arg = NULL, + .start = 0, + .size = num_node_state(N_MEMORY), + .align = 1, + .min_chunk = 1, + .max_threads = num_node_state(N_MEMORY), + .numa_aware = true, + }; + + padata_do_multithreaded(&job); +} + static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) { unsigned long i; @@ -3602,6 +3620,14 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) return; } + /* hugetlb_hstate_alloc_pages will be called many times, init huge_boot_pages once*/ + if (huge_boot_pages[0].next == NULL) { + int i = 0; + + for (i = 0; i < MAX_NUMNODES; i++) + INIT_LIST_HEAD(&huge_boot_pages[i]); + } + /* do node specific alloc */ if (hugetlb_hstate_alloc_pages_specific_nodes(h)) return;
Optimizing the initialization speed of 1G huge pages through parallelization. 1G hugetlbs are allocated from bootmem, a process that is already very fast and does not currently require optimization. Therefore, we focus on parallelizing only the initialization phase in `gather_bootmem_prealloc`. Here are some test results: test no patch(ms) patched(ms) saved ------------------- -------------- ------------- -------- 256c2t(4 node) 1G 4745 2024 57.34% 128c1t(2 node) 1G 3358 1712 49.02% 12t 1G 77000 18300 76.23% Signed-off-by: Gang Li <gang.li@linux.dev> Tested-by: David Rientjes <rientjes@google.com> --- include/linux/hugetlb.h | 2 +- mm/hugetlb.c | 42 +++++++++++++++++++++++++++++++++-------- 2 files changed, 35 insertions(+), 9 deletions(-)