| Message ID | 20240729112534.3416707-7-alexs@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/zsmalloc: add zpdesc memory descriptor for zswap.zpool | expand |
On Mon, Jul 29, 2024 at 07:25:18PM +0800, alexs@kernel.org wrote: > From: Alex Shi <alexs@kernel.org> > > Introduce a few helper functions for conversion to convert create_page_chain() > to use zpdesc, then use zpdesc in replace_sub_page() too. As a general note, I've been having trouble keeping track of your helper functions throughout your patchset. Things get confusing when helper functions are "add-ons" to patches and are then replaced/rewritten in various subsequent patches - might just be me though. > Originally-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> > Signed-off-by: Alex Shi <alexs@kernel.org> > --- > mm/zpdesc.h | 6 +++ > mm/zsmalloc.c | 115 +++++++++++++++++++++++++++++++++----------------- > 2 files changed, 82 insertions(+), 39 deletions(-) > > diff --git a/mm/zpdesc.h b/mm/zpdesc.h > index 79ec40b03956..2293453f5d57 100644 > --- a/mm/zpdesc.h > +++ b/mm/zpdesc.h > @@ -102,4 +102,10 @@ static inline struct zpdesc *pfn_zpdesc(unsigned long pfn) > { > return page_zpdesc(pfn_to_page(pfn)); > } > + > +static inline void __zpdesc_set_movable(struct zpdesc *zpdesc, > + const struct movable_operations *mops) > +{ > + __SetPageMovable(zpdesc_page(zpdesc), mops); > +} > #endif > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > index bbc165cb587d..a8f390beeab8 100644 > --- a/mm/zsmalloc.c > +++ b/mm/zsmalloc.c > @@ -248,6 +248,41 @@ static inline void *zpdesc_kmap_atomic(struct zpdesc *zpdesc) > return kmap_atomic(zpdesc_page(zpdesc)); > } > > +static inline void zpdesc_set_zspage(struct zpdesc *zpdesc, > + struct zspage *zspage) > +{ > + zpdesc->zspage = zspage; > +} > + > +static inline void zpdesc_set_first(struct zpdesc *zpdesc) > +{ > + SetPagePrivate(zpdesc_page(zpdesc)); > +} > + I'm not a fan of the names above. IMO, naming should follow some semblance of consistency regarding their purpose (or have comments that describe their purpose instead). At a glance zpdesc_set_zspage() and zpdesc_set_first() sound like they are doing similar things, but I don't think they serve similar purposes? > +static inline void zpdesc_inc_zone_page_state(struct zpdesc *zpdesc) > +{ > + inc_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); > +} > + > +static inline void zpdesc_dec_zone_page_state(struct zpdesc *zpdesc) > +{ > + dec_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); > +} > + > +static inline struct zpdesc *alloc_zpdesc(gfp_t gfp) > +{ > + struct page *page = alloc_page(gfp); > + > + return page_zpdesc(page); > +} > + > +static inline void free_zpdesc(struct zpdesc *zpdesc) > +{ > + struct page *page = zpdesc_page(zpdesc); > + > + __free_page(page); > +} > +
On 8/3/24 3:09 AM, Vishal Moola wrote: > On Mon, Jul 29, 2024 at 07:25:18PM +0800, alexs@kernel.org wrote: >> From: Alex Shi <alexs@kernel.org> >> >> Introduce a few helper functions for conversion to convert create_page_chain() >> to use zpdesc, then use zpdesc in replace_sub_page() too. > > As a general note, I've been having trouble keeping track of your helper > functions throughout your patchset. Things get confusing when helper > functions are "add-ons" to patches and are then replaced/rewritten > in various subsequent patches - might just be me though. Right, maybe too much helper doesn't give necessary help. > >> Originally-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> >> Signed-off-by: Alex Shi <alexs@kernel.org> >> --- >> mm/zpdesc.h | 6 +++ >> mm/zsmalloc.c | 115 +++++++++++++++++++++++++++++++++----------------- >> 2 files changed, 82 insertions(+), 39 deletions(-) >> >> diff --git a/mm/zpdesc.h b/mm/zpdesc.h >> index 79ec40b03956..2293453f5d57 100644 >> --- a/mm/zpdesc.h >> +++ b/mm/zpdesc.h >> @@ -102,4 +102,10 @@ static inline struct zpdesc *pfn_zpdesc(unsigned long pfn) >> { >> return page_zpdesc(pfn_to_page(pfn)); >> } >> + >> +static inline void __zpdesc_set_movable(struct zpdesc *zpdesc, >> + const struct movable_operations *mops) >> +{ >> + __SetPageMovable(zpdesc_page(zpdesc), mops); >> +} >> #endif >> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c >> index bbc165cb587d..a8f390beeab8 100644 >> --- a/mm/zsmalloc.c >> +++ b/mm/zsmalloc.c >> @@ -248,6 +248,41 @@ static inline void *zpdesc_kmap_atomic(struct zpdesc *zpdesc) >> return kmap_atomic(zpdesc_page(zpdesc)); >> } >> >> +static inline void zpdesc_set_zspage(struct zpdesc *zpdesc, >> + struct zspage *zspage) >> +{ >> + zpdesc->zspage = zspage; >> +} >> + >> +static inline void zpdesc_set_first(struct zpdesc *zpdesc) >> +{ >> + SetPagePrivate(zpdesc_page(zpdesc)); >> +} >> + > > I'm not a fan of the names above. IMO, naming should follow some > semblance of consistency regarding their purpose (or have comments > that describe their purpose instead). > > At a glance zpdesc_set_zspage() and zpdesc_set_first() sound like they > are doing similar things, but I don't think they serve similar purposes? zpdesc_set_zspage() only used in one place, a helper maynot needed. Let me remove it. Same thing for the alloc_zpdesc() and free_zpdesc(), they could be merge into using place. Thanks Alex > >> +static inline void zpdesc_inc_zone_page_state(struct zpdesc *zpdesc) >> +{ >> + inc_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); >> +} >> + >> +static inline void zpdesc_dec_zone_page_state(struct zpdesc *zpdesc) >> +{ >> + dec_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); >> +} >> + >> +static inline struct zpdesc *alloc_zpdesc(gfp_t gfp) >> +{ >> + struct page *page = alloc_page(gfp); >> + >> + return page_zpdesc(page); >> +} >> + >> +static inline void free_zpdesc(struct zpdesc *zpdesc) >> +{ >> + struct page *page = zpdesc_page(zpdesc); >> + >> + __free_page(page); >> +} >> + >
On Mon, Aug 05, 2024 at 04:20:15PM +0800, Alex Shi wrote: > > > On 8/3/24 3:09 AM, Vishal Moola wrote: > > On Mon, Jul 29, 2024 at 07:25:18PM +0800, alexs@kernel.org wrote: > >> From: Alex Shi <alexs@kernel.org> > >> > >> Introduce a few helper functions for conversion to convert create_page_chain() > >> to use zpdesc, then use zpdesc in replace_sub_page() too. > > > > As a general note, I've been having trouble keeping track of your helper > > functions throughout your patchset. Things get confusing when helper > > functions are "add-ons" to patches and are then replaced/rewritten > > in various subsequent patches - might just be me though. > > Right, maybe too much helper doesn't give necessary help. > > > > >> Originally-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> > >> Signed-off-by: Alex Shi <alexs@kernel.org> > >> --- > >> mm/zpdesc.h | 6 +++ > >> mm/zsmalloc.c | 115 +++++++++++++++++++++++++++++++++----------------- > >> 2 files changed, 82 insertions(+), 39 deletions(-) > >> > >> diff --git a/mm/zpdesc.h b/mm/zpdesc.h > >> index 79ec40b03956..2293453f5d57 100644 > >> --- a/mm/zpdesc.h > >> +++ b/mm/zpdesc.h > >> @@ -102,4 +102,10 @@ static inline struct zpdesc *pfn_zpdesc(unsigned long pfn) > >> { > >> return page_zpdesc(pfn_to_page(pfn)); > >> } > >> + > >> +static inline void __zpdesc_set_movable(struct zpdesc *zpdesc, > >> + const struct movable_operations *mops) > >> +{ > >> + __SetPageMovable(zpdesc_page(zpdesc), mops); > >> +} > >> #endif > >> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > >> index bbc165cb587d..a8f390beeab8 100644 > >> --- a/mm/zsmalloc.c > >> +++ b/mm/zsmalloc.c > >> @@ -248,6 +248,41 @@ static inline void *zpdesc_kmap_atomic(struct zpdesc *zpdesc) > >> return kmap_atomic(zpdesc_page(zpdesc)); > >> } > >> > >> +static inline void zpdesc_set_zspage(struct zpdesc *zpdesc, > >> + struct zspage *zspage) > >> +{ > >> + zpdesc->zspage = zspage; > >> +} > >> + > >> +static inline void zpdesc_set_first(struct zpdesc *zpdesc) > >> +{ > >> + SetPagePrivate(zpdesc_page(zpdesc)); > >> +} > >> + > > > > I'm not a fan of the names above. IMO, naming should follow some > > semblance of consistency regarding their purpose (or have comments > > that describe their purpose instead). > > > > At a glance zpdesc_set_zspage() and zpdesc_set_first() sound like they > > are doing similar things, but I don't think they serve similar purposes? > > zpdesc_set_zspage() only used in one place, a helper maynot needed. Let me remove it. > Same thing for the alloc_zpdesc() and free_zpdesc(), they could be merge into using place. alloc_zpdesc() and free_zpdesc() are fine as is. The helper functions will be useful whenever memdescs can be allocated on their own, so its better to introduce it now. > Thanks > Alex > > > >> +static inline void zpdesc_inc_zone_page_state(struct zpdesc *zpdesc) > >> +{ > >> + inc_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); > >> +} > >> + > >> +static inline void zpdesc_dec_zone_page_state(struct zpdesc *zpdesc) > >> +{ > >> + dec_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); > >> +} > >> + > >> +static inline struct zpdesc *alloc_zpdesc(gfp_t gfp) > >> +{ > >> + struct page *page = alloc_page(gfp); > >> + > >> + return page_zpdesc(page); > >> +} > >> + > >> +static inline void free_zpdesc(struct zpdesc *zpdesc) > >> +{ > >> + struct page *page = zpdesc_page(zpdesc); > >> + > >> + __free_page(page); > >> +} > >> + > >
On 8/9/24 2:25 AM, Vishal Moola wrote: >>> I'm not a fan of the names above. IMO, naming should follow some >>> semblance of consistency regarding their purpose (or have comments >>> that describe their purpose instead). >>> >>> At a glance zpdesc_set_zspage() and zpdesc_set_first() sound like they >>> are doing similar things, but I don't think they serve similar purposes? >> zpdesc_set_zspage() only used in one place, a helper maynot needed. Let me remove it. >> Same thing for the alloc_zpdesc() and free_zpdesc(), they could be merge into using place. > alloc_zpdesc() and free_zpdesc() are fine as is. The helper functions > will be useful whenever memdescs can be allocated on their own, so its > better to introduce it now. Thanks for suggestion. will recover them in next version, maybe tomorrow if no more comments.
diff --git a/mm/zpdesc.h b/mm/zpdesc.h index 79ec40b03956..2293453f5d57 100644 --- a/mm/zpdesc.h +++ b/mm/zpdesc.h @@ -102,4 +102,10 @@ static inline struct zpdesc *pfn_zpdesc(unsigned long pfn) { return page_zpdesc(pfn_to_page(pfn)); } + +static inline void __zpdesc_set_movable(struct zpdesc *zpdesc, + const struct movable_operations *mops) +{ + __SetPageMovable(zpdesc_page(zpdesc), mops); +} #endif diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index bbc165cb587d..a8f390beeab8 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -248,6 +248,41 @@ static inline void *zpdesc_kmap_atomic(struct zpdesc *zpdesc) return kmap_atomic(zpdesc_page(zpdesc)); } +static inline void zpdesc_set_zspage(struct zpdesc *zpdesc, + struct zspage *zspage) +{ + zpdesc->zspage = zspage; +} + +static inline void zpdesc_set_first(struct zpdesc *zpdesc) +{ + SetPagePrivate(zpdesc_page(zpdesc)); +} + +static inline void zpdesc_inc_zone_page_state(struct zpdesc *zpdesc) +{ + inc_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); +} + +static inline void zpdesc_dec_zone_page_state(struct zpdesc *zpdesc) +{ + dec_zone_page_state(zpdesc_page(zpdesc), NR_ZSPAGES); +} + +static inline struct zpdesc *alloc_zpdesc(gfp_t gfp) +{ + struct page *page = alloc_page(gfp); + + return page_zpdesc(page); +} + +static inline void free_zpdesc(struct zpdesc *zpdesc) +{ + struct page *page = zpdesc_page(zpdesc); + + __free_page(page); +} + struct zspage { struct { unsigned int huge:HUGE_BITS; @@ -954,35 +989,35 @@ static void init_zspage(struct size_class *class, struct zspage *zspage) } static void create_page_chain(struct size_class *class, struct zspage *zspage, - struct page *pages[]) + struct zpdesc *zpdescs[]) { int i; - struct page *page; - struct page *prev_page = NULL; - int nr_pages = class->pages_per_zspage; + struct zpdesc *zpdesc; + struct zpdesc *prev_zpdesc = NULL; + int nr_zpdescs = class->pages_per_zspage; /* * Allocate individual pages and link them together as: - * 1. all pages are linked together using page->index - * 2. each sub-page point to zspage using page->private + * 1. all pages are linked together using zpdesc->next + * 2. each sub-page point to zspage using zpdesc->zspage * - * we set PG_private to identify the first page (i.e. no other sub-page + * we set PG_private to identify the first zpdesc (i.e. no other zpdesc * has this flag set). */ - for (i = 0; i < nr_pages; i++) { - page = pages[i]; - set_page_private(page, (unsigned long)zspage); - page->index = 0; + for (i = 0; i < nr_zpdescs; i++) { + zpdesc = zpdescs[i]; + zpdesc_set_zspage(zpdesc, zspage); + zpdesc->next = NULL; if (i == 0) { - zspage->first_zpdesc = page_zpdesc(page); - SetPagePrivate(page); + zspage->first_zpdesc = zpdesc; + zpdesc_set_first(zpdesc); if (unlikely(class->objs_per_zspage == 1 && class->pages_per_zspage == 1)) SetZsHugePage(zspage); } else { - prev_page->index = (unsigned long)page; + prev_zpdesc->next = zpdesc; } - prev_page = page; + prev_zpdesc = zpdesc; } } @@ -994,7 +1029,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool, gfp_t gfp) { int i; - struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE]; + struct zpdesc *zpdescs[ZS_MAX_PAGES_PER_ZSPAGE]; struct zspage *zspage = cache_alloc_zspage(pool, gfp); if (!zspage) @@ -1004,25 +1039,25 @@ static struct zspage *alloc_zspage(struct zs_pool *pool, migrate_lock_init(zspage); for (i = 0; i < class->pages_per_zspage; i++) { - struct page *page; + struct zpdesc *zpdesc; - page = alloc_page(gfp); - if (!page) { + zpdesc = alloc_zpdesc(gfp); + if (!zpdesc) { while (--i >= 0) { - dec_zone_page_state(pages[i], NR_ZSPAGES); - __ClearPageZsmalloc(pages[i]); - __free_page(pages[i]); + zpdesc_dec_zone_page_state(zpdescs[i]); + __ClearPageZsmalloc(zpdesc_page(zpdescs[i])); + free_zpdesc(zpdescs[i]); } cache_free_zspage(pool, zspage); return NULL; } - __SetPageZsmalloc(page); + __SetPageZsmalloc(zpdesc_page(zpdesc)); - inc_zone_page_state(page, NR_ZSPAGES); - pages[i] = page; + zpdesc_inc_zone_page_state(zpdesc); + zpdescs[i] = zpdesc; } - create_page_chain(class, zspage, pages); + create_page_chain(class, zspage, zpdescs); init_zspage(class, zspage); zspage->pool = pool; zspage->class = class->index; @@ -1753,26 +1788,28 @@ static void migrate_write_unlock(struct zspage *zspage) static const struct movable_operations zsmalloc_mops; static void replace_sub_page(struct size_class *class, struct zspage *zspage, - struct page *newpage, struct page *oldpage) + struct zpdesc *newzpdesc, struct zpdesc *oldzpdesc) { - struct page *page; - struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE] = {NULL, }; + struct zpdesc *zpdesc; + struct zpdesc *zpdescs[ZS_MAX_PAGES_PER_ZSPAGE] = {NULL, }; + unsigned int first_obj_offset; int idx = 0; - page = get_first_page(zspage); + zpdesc = get_first_zpdesc(zspage); do { - if (page == oldpage) - pages[idx] = newpage; + if (zpdesc == oldzpdesc) + zpdescs[idx] = newzpdesc; else - pages[idx] = page; + zpdescs[idx] = zpdesc; idx++; - } while ((page = get_next_page(page)) != NULL); + } while ((zpdesc = get_next_zpdesc(zpdesc)) != NULL); - create_page_chain(class, zspage, pages); - set_first_obj_offset(newpage, get_first_obj_offset(oldpage)); + create_page_chain(class, zspage, zpdescs); + first_obj_offset = get_first_obj_offset(zpdesc_page(oldzpdesc)); + set_first_obj_offset(zpdesc_page(newzpdesc), first_obj_offset); if (unlikely(ZsHugePage(zspage))) - newpage->index = oldpage->index; - __SetPageMovable(newpage, &zsmalloc_mops); + newzpdesc->handle = oldzpdesc->handle; + __zpdesc_set_movable(newzpdesc, &zsmalloc_mops); } static bool zs_page_isolate(struct page *page, isolate_mode_t mode) @@ -1845,7 +1882,7 @@ static int zs_page_migrate(struct page *newpage, struct page *page, } kunmap_atomic(s_addr); - replace_sub_page(class, zspage, newpage, page); + replace_sub_page(class, zspage, page_zpdesc(newpage), page_zpdesc(page)); /* * Since we complete the data copy and set up new zspage structure, * it's okay to release migration_lock.