| Message ID | 20220827104600.1813214-3-liushixin2@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Delay the initializaton of zswap | expand |
On Sat, Aug 27, 2022 at 12:12 PM Liu Shixin <liushixin2@huawei.com> wrote: > > Since we are supported to delay zswap initializaton, we need to invoke > ops->init for the swap device which is already online when register > backend. > > This patch is a revert of f328c1d16e4c ("frontswap: simplify frontswap_register_ops") > and 633423a09cb5 ("mm: mark swap_lock and swap_active_head static") > > Signed-off-by: Liu Shixin <liushixin2@huawei.com> Sorry, is this the revert of 2 patches at the same time? I would rather not do it like that. Thanks, Vitaly > --- > include/linux/swapfile.h | 2 ++ > mm/frontswap.c | 47 ++++++++++++++++++++++++++++++++++++++++ > mm/swapfile.c | 4 ++-- > 3 files changed, 51 insertions(+), 2 deletions(-) > > diff --git a/include/linux/swapfile.h b/include/linux/swapfile.h > index 2fbcc9afd814..75fc069594a5 100644 > --- a/include/linux/swapfile.h > +++ b/include/linux/swapfile.h > @@ -6,6 +6,8 @@ > * these were static in swapfile.c but frontswap.c needs them and we don't > * want to expose them to the dozens of source files that include swap.h > */ > +extern spinlock_t swap_lock; > +extern struct plist_head swap_active_head; > extern struct swap_info_struct *swap_info[]; > extern unsigned long generic_max_swapfile_size(void); > /* Maximum swapfile size supported for the arch (not inclusive). */ > diff --git a/mm/frontswap.c b/mm/frontswap.c > index 620f95af81dd..449e6f499b88 100644 > --- a/mm/frontswap.c > +++ b/mm/frontswap.c > @@ -96,11 +96,58 @@ static inline void inc_frontswap_invalidates(void) { } > */ > int frontswap_register_ops(const struct frontswap_ops *ops) > { > + DECLARE_BITMAP(a, MAX_SWAPFILES); > + DECLARE_BITMAP(b, MAX_SWAPFILES); > + struct swap_info_struct *si; > + unsigned int i; > + > if (frontswap_ops) > return -EINVAL; > > + bitmap_zero(a, MAX_SWAPFILES); > + bitmap_zero(b, MAX_SWAPFILES); > + > + spin_lock(&swap_lock); > + plist_for_each_entry(si, &swap_active_head, list) { > + if (!WARN_ON(!si->frontswap_map)) > + __set_bit(si->type, a); > + } > + spin_unlock(&swap_lock); > + > + /* the new ops needs to know the currently active swap devices */ > + for_each_set_bit(i, a, MAX_SWAPFILES) { > + pr_err("init frontswap_ops\n"); > + ops->init(i); > + } > + > frontswap_ops = ops; > static_branch_inc(&frontswap_enabled_key); > + > + spin_lock(&swap_lock); > + plist_for_each_entry(si, &swap_active_head, list) { > + if (si->frontswap_map) > + __set_bit(si->type, b); > + } > + spin_unlock(&swap_lock); > + > + /* > + * On the very unlikely chance that a swap device was added or > + * removed between setting the "a" list bits and the ops init > + * calls, we re-check and do init or invalidate for any changed > + * bits. > + */ > + if (unlikely(!bitmap_equal(a, b, MAX_SWAPFILES))) { > + for (i = 0; i < MAX_SWAPFILES; i++) { > + if (!test_bit(i, a) && test_bit(i, b)) { > + pr_err("init frontswap_ops re\n"); > + ops->init(i); > + } else if (test_bit(i, a) && !test_bit(i, b)) { > + pr_err("inval frontswap_ops re\n"); > + ops->invalidate_area(i); > + } > + } > + } > + > return 0; > } > > diff --git a/mm/swapfile.c b/mm/swapfile.c > index 469d9af86be2..d383b282f269 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -51,7 +51,7 @@ static bool swap_count_continued(struct swap_info_struct *, pgoff_t, > unsigned char); > static void free_swap_count_continuations(struct swap_info_struct *); > > -static DEFINE_SPINLOCK(swap_lock); > +DEFINE_SPINLOCK(swap_lock); > static unsigned int nr_swapfiles; > atomic_long_t nr_swap_pages; > /* > @@ -77,7 +77,7 @@ static const char Unused_offset[] = "Unused swap offset entry "; > * all active swap_info_structs > * protected with swap_lock, and ordered by priority. > */ > -static PLIST_HEAD(swap_active_head); > +PLIST_HEAD(swap_active_head); > > /* > * all available (active, not full) swap_info_structs > -- > 2.25.1 >
On 2022/8/29 4:47, Vitaly Wool wrote: > On Sat, Aug 27, 2022 at 12:12 PM Liu Shixin <liushixin2@huawei.com> wrote: >> Since we are supported to delay zswap initializaton, we need to invoke >> ops->init for the swap device which is already online when register >> backend. >> >> This patch is a revert of f328c1d16e4c ("frontswap: simplify frontswap_register_ops") >> and 633423a09cb5 ("mm: mark swap_lock and swap_active_head static") >> >> Signed-off-by: Liu Shixin <liushixin2@huawei.com> > Sorry, is this the revert of 2 patches at the same time? I would > rather not do it like that. > > Thanks, > Vitaly Thanks for your advice, I'll split it to two patches and resend it. >> --- >> include/linux/swapfile.h | 2 ++ >> mm/frontswap.c | 47 ++++++++++++++++++++++++++++++++++++++++ >> mm/swapfile.c | 4 ++-- >> 3 files changed, 51 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/swapfile.h b/include/linux/swapfile.h >> index 2fbcc9afd814..75fc069594a5 100644 >> --- a/include/linux/swapfile.h >> +++ b/include/linux/swapfile.h >> @@ -6,6 +6,8 @@ >> * these were static in swapfile.c but frontswap.c needs them and we don't >> * want to expose them to the dozens of source files that include swap.h >> */ >> +extern spinlock_t swap_lock; >> +extern struct plist_head swap_active_head; >> extern struct swap_info_struct *swap_info[]; >> extern unsigned long generic_max_swapfile_size(void); >> /* Maximum swapfile size supported for the arch (not inclusive). */ >> diff --git a/mm/frontswap.c b/mm/frontswap.c >> index 620f95af81dd..449e6f499b88 100644 >> --- a/mm/frontswap.c >> +++ b/mm/frontswap.c >> @@ -96,11 +96,58 @@ static inline void inc_frontswap_invalidates(void) { } >> */ >> int frontswap_register_ops(const struct frontswap_ops *ops) >> { >> + DECLARE_BITMAP(a, MAX_SWAPFILES); >> + DECLARE_BITMAP(b, MAX_SWAPFILES); >> + struct swap_info_struct *si; >> + unsigned int i; >> + >> if (frontswap_ops) >> return -EINVAL; >> >> + bitmap_zero(a, MAX_SWAPFILES); >> + bitmap_zero(b, MAX_SWAPFILES); >> + >> + spin_lock(&swap_lock); >> + plist_for_each_entry(si, &swap_active_head, list) { >> + if (!WARN_ON(!si->frontswap_map)) >> + __set_bit(si->type, a); >> + } >> + spin_unlock(&swap_lock); >> + >> + /* the new ops needs to know the currently active swap devices */ >> + for_each_set_bit(i, a, MAX_SWAPFILES) { >> + pr_err("init frontswap_ops\n"); >> + ops->init(i); >> + } >> + >> frontswap_ops = ops; >> static_branch_inc(&frontswap_enabled_key); >> + >> + spin_lock(&swap_lock); >> + plist_for_each_entry(si, &swap_active_head, list) { >> + if (si->frontswap_map) >> + __set_bit(si->type, b); >> + } >> + spin_unlock(&swap_lock); >> + >> + /* >> + * On the very unlikely chance that a swap device was added or >> + * removed between setting the "a" list bits and the ops init >> + * calls, we re-check and do init or invalidate for any changed >> + * bits. >> + */ >> + if (unlikely(!bitmap_equal(a, b, MAX_SWAPFILES))) { >> + for (i = 0; i < MAX_SWAPFILES; i++) { >> + if (!test_bit(i, a) && test_bit(i, b)) { >> + pr_err("init frontswap_ops re\n"); >> + ops->init(i); >> + } else if (test_bit(i, a) && !test_bit(i, b)) { >> + pr_err("inval frontswap_ops re\n"); >> + ops->invalidate_area(i); >> + } >> + } >> + } >> + >> return 0; >> } >> >> diff --git a/mm/swapfile.c b/mm/swapfile.c >> index 469d9af86be2..d383b282f269 100644 >> --- a/mm/swapfile.c >> +++ b/mm/swapfile.c >> @@ -51,7 +51,7 @@ static bool swap_count_continued(struct swap_info_struct *, pgoff_t, >> unsigned char); >> static void free_swap_count_continuations(struct swap_info_struct *); >> >> -static DEFINE_SPINLOCK(swap_lock); >> +DEFINE_SPINLOCK(swap_lock); >> static unsigned int nr_swapfiles; >> atomic_long_t nr_swap_pages; >> /* >> @@ -77,7 +77,7 @@ static const char Unused_offset[] = "Unused swap offset entry "; >> * all active swap_info_structs >> * protected with swap_lock, and ordered by priority. >> */ >> -static PLIST_HEAD(swap_active_head); >> +PLIST_HEAD(swap_active_head); >> >> /* >> * all available (active, not full) swap_info_structs >> -- >> 2.25.1 >> > . >
diff --git a/include/linux/swapfile.h b/include/linux/swapfile.h index 2fbcc9afd814..75fc069594a5 100644 --- a/include/linux/swapfile.h +++ b/include/linux/swapfile.h @@ -6,6 +6,8 @@ * these were static in swapfile.c but frontswap.c needs them and we don't * want to expose them to the dozens of source files that include swap.h */ +extern spinlock_t swap_lock; +extern struct plist_head swap_active_head; extern struct swap_info_struct *swap_info[]; extern unsigned long generic_max_swapfile_size(void); /* Maximum swapfile size supported for the arch (not inclusive). */ diff --git a/mm/frontswap.c b/mm/frontswap.c index 620f95af81dd..449e6f499b88 100644 --- a/mm/frontswap.c +++ b/mm/frontswap.c @@ -96,11 +96,58 @@ static inline void inc_frontswap_invalidates(void) { } */ int frontswap_register_ops(const struct frontswap_ops *ops) { + DECLARE_BITMAP(a, MAX_SWAPFILES); + DECLARE_BITMAP(b, MAX_SWAPFILES); + struct swap_info_struct *si; + unsigned int i; + if (frontswap_ops) return -EINVAL; + bitmap_zero(a, MAX_SWAPFILES); + bitmap_zero(b, MAX_SWAPFILES); + + spin_lock(&swap_lock); + plist_for_each_entry(si, &swap_active_head, list) { + if (!WARN_ON(!si->frontswap_map)) + __set_bit(si->type, a); + } + spin_unlock(&swap_lock); + + /* the new ops needs to know the currently active swap devices */ + for_each_set_bit(i, a, MAX_SWAPFILES) { + pr_err("init frontswap_ops\n"); + ops->init(i); + } + frontswap_ops = ops; static_branch_inc(&frontswap_enabled_key); + + spin_lock(&swap_lock); + plist_for_each_entry(si, &swap_active_head, list) { + if (si->frontswap_map) + __set_bit(si->type, b); + } + spin_unlock(&swap_lock); + + /* + * On the very unlikely chance that a swap device was added or + * removed between setting the "a" list bits and the ops init + * calls, we re-check and do init or invalidate for any changed + * bits. + */ + if (unlikely(!bitmap_equal(a, b, MAX_SWAPFILES))) { + for (i = 0; i < MAX_SWAPFILES; i++) { + if (!test_bit(i, a) && test_bit(i, b)) { + pr_err("init frontswap_ops re\n"); + ops->init(i); + } else if (test_bit(i, a) && !test_bit(i, b)) { + pr_err("inval frontswap_ops re\n"); + ops->invalidate_area(i); + } + } + } + return 0; } diff --git a/mm/swapfile.c b/mm/swapfile.c index 469d9af86be2..d383b282f269 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -51,7 +51,7 @@ static bool swap_count_continued(struct swap_info_struct *, pgoff_t, unsigned char); static void free_swap_count_continuations(struct swap_info_struct *); -static DEFINE_SPINLOCK(swap_lock); +DEFINE_SPINLOCK(swap_lock); static unsigned int nr_swapfiles; atomic_long_t nr_swap_pages; /* @@ -77,7 +77,7 @@ static const char Unused_offset[] = "Unused swap offset entry "; * all active swap_info_structs * protected with swap_lock, and ordered by priority. */ -static PLIST_HEAD(swap_active_head); +PLIST_HEAD(swap_active_head); /* * all available (active, not full) swap_info_structs
Since we are supported to delay zswap initializaton, we need to invoke ops->init for the swap device which is already online when register backend. This patch is a revert of f328c1d16e4c ("frontswap: simplify frontswap_register_ops") and 633423a09cb5 ("mm: mark swap_lock and swap_active_head static") Signed-off-by: Liu Shixin <liushixin2@huawei.com> --- include/linux/swapfile.h | 2 ++ mm/frontswap.c | 47 ++++++++++++++++++++++++++++++++++++++++ mm/swapfile.c | 4 ++-- 3 files changed, 51 insertions(+), 2 deletions(-)