| Message ID | 20220510113809.80626-1-zhengqi.arch@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] mm: fix missing handler for __GFP_NOWARN | expand |
On Tue, 10 May 2022 19:38:08 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote: > We expect no warnings to be issued when we specify __GFP_NOWARN, but > currently in paths like alloc_pages() and kmalloc(), there are still > some warnings printed, fix it. Looks sane to me. > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -35,6 +35,17 @@ struct folio_batch; > /* Do not use these with a slab allocator */ > #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) > > +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ > + static bool __section(".data.once") __warned; \ > + int __ret_warn_once = !!(cond); \ > + \ > + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ > + __warned = true; \ > + WARN_ON(1); \ > + } \ > + unlikely(__ret_warn_once); \ > +}) I don't think WARN_ON_ONCE_GFP is a good name for this. But WARN_ON_ONCE_IF_NOT_GFP_NOWARN is too long :( WARN_ON_ONCE_NOWARN might be better. No strong opinion here, really. > @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > * We also sanity check to catch abuse of atomic reserves being used by > * callers that are not in atomic context. > */ > - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) > + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) > gfp_mask &= ~__GFP_ATOMIC; > > retry_cpuset: I dropped this hunk - Neil's "mm: discard __GFP_ATOMIC" (https://lkml.kernel.org/r/163712397076.13692.4727608274002939094@noble.neil.brown.name) deleted this code.
On 2022/5/11 2:59 AM, Andrew Morton wrote: > On Tue, 10 May 2022 19:38:08 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote: > >> We expect no warnings to be issued when we specify __GFP_NOWARN, but >> currently in paths like alloc_pages() and kmalloc(), there are still >> some warnings printed, fix it. > > Looks sane to me. > >> --- a/mm/internal.h >> +++ b/mm/internal.h >> @@ -35,6 +35,17 @@ struct folio_batch; >> /* Do not use these with a slab allocator */ >> #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) >> >> +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ >> + static bool __section(".data.once") __warned; \ >> + int __ret_warn_once = !!(cond); \ >> + \ >> + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ >> + __warned = true; \ >> + WARN_ON(1); \ >> + } \ >> + unlikely(__ret_warn_once); \ >> +}) > > I don't think WARN_ON_ONCE_GFP is a good name for this. But > WARN_ON_ONCE_IF_NOT_GFP_NOWARN is too long :( > > WARN_ON_ONCE_NOWARN might be better. No strong opinion here, really. I've thought about WARN_ON_ONCE_NOWARN, but I feel a little weird putting 'WARN' and 'NOWARN' together, how about WARN_ON_ONCE_IF_ALLOWED? > >> @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, >> * We also sanity check to catch abuse of atomic reserves being used by >> * callers that are not in atomic context. >> */ >> - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >> - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) >> + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >> + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) >> gfp_mask &= ~__GFP_ATOMIC; >> >> retry_cpuset: > > I dropped this hunk - Neil's "mm: discard __GFP_ATOMIC" > (https://lkml.kernel.org/r/163712397076.13692.4727608274002939094@noble.neil.brown.name) > deleted this code. > This series is based on v5.18-rc5, I will rebase it to the latest next branch and check if there are any missing WARN_ON_ONCEs that are not being handled. Thanks, Qi
On Wed, 11 May 2022 10:19:48 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote: > > ,,, > >> --- a/mm/internal.h > >> +++ b/mm/internal.h > >> @@ -35,6 +35,17 @@ struct folio_batch; > >> /* Do not use these with a slab allocator */ > >> #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) > >> > >> +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ > >> + static bool __section(".data.once") __warned; \ > >> + int __ret_warn_once = !!(cond); \ > >> + \ > >> + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ > >> + __warned = true; \ > >> + WARN_ON(1); \ > >> + } \ > >> + unlikely(__ret_warn_once); \ > >> +}) > > > > I don't think WARN_ON_ONCE_GFP is a good name for this. But > > WARN_ON_ONCE_IF_NOT_GFP_NOWARN is too long :( > > > > WARN_ON_ONCE_NOWARN might be better. No strong opinion here, really. > > I've thought about WARN_ON_ONCE_NOWARN, but I feel a little weird > putting 'WARN' and 'NOWARN' together, how about WARN_ON_ONCE_IF_ALLOWED? I dunno. WARN_ON_ONCE_GFP isn't too bad I suppose. Add a comment over the definition explaining it? > > > >> @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > >> * We also sanity check to catch abuse of atomic reserves being used by > >> * callers that are not in atomic context. > >> */ > >> - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > >> - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) > >> + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > >> + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) > >> gfp_mask &= ~__GFP_ATOMIC; > >> > >> retry_cpuset: > > > > I dropped this hunk - Neil's "mm: discard __GFP_ATOMIC" > > (https://lkml.kernel.org/r/163712397076.13692.4727608274002939094@noble.neil.brown.name) > > deleted this code. > > > > This series is based on v5.18-rc5, I will rebase it to the latest next > branch and check if there are any missing WARN_ON_ONCEs that are not > being handled. Against git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm branch mm-unstable, please. That ends up in linux-next, with a delay.
On 2022/5/11 10:32 AM, Andrew Morton wrote: > On Wed, 11 May 2022 10:19:48 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote: > >> >> ,,, >>>> --- a/mm/internal.h >>>> +++ b/mm/internal.h >>>> @@ -35,6 +35,17 @@ struct folio_batch; >>>> /* Do not use these with a slab allocator */ >>>> #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) >>>> >>>> +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ >>>> + static bool __section(".data.once") __warned; \ >>>> + int __ret_warn_once = !!(cond); \ >>>> + \ >>>> + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ >>>> + __warned = true; \ >>>> + WARN_ON(1); \ >>>> + } \ >>>> + unlikely(__ret_warn_once); \ >>>> +}) >>> >>> I don't think WARN_ON_ONCE_GFP is a good name for this. But >>> WARN_ON_ONCE_IF_NOT_GFP_NOWARN is too long :( >>> >>> WARN_ON_ONCE_NOWARN might be better. No strong opinion here, really. >> >> I've thought about WARN_ON_ONCE_NOWARN, but I feel a little weird >> putting 'WARN' and 'NOWARN' together, how about WARN_ON_ONCE_IF_ALLOWED? > > I dunno. WARN_ON_ONCE_GFP isn't too bad I suppose. Add a comment over > the definition explaining it? OK, I will add a comment to it. > >>> >>>> @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, >>>> * We also sanity check to catch abuse of atomic reserves being used by >>>> * callers that are not in atomic context. >>>> */ >>>> - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >>>> - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) >>>> + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >>>> + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) >>>> gfp_mask &= ~__GFP_ATOMIC; >>>> >>>> retry_cpuset: >>> >>> I dropped this hunk - Neil's "mm: discard __GFP_ATOMIC" >>> (https://lkml.kernel.org/r/163712397076.13692.4727608274002939094@noble.neil.brown.name) >>> deleted this code. >>> >> >> This series is based on v5.18-rc5, I will rebase it to the latest next >> branch and check if there are any missing WARN_ON_ONCEs that are not >> being handled. > > Against git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm branch > mm-unstable, please. That ends up in linux-next, with a delay. OK, will do.
On 2022/5/10 7:38 PM, Qi Zheng wrote: > We expect no warnings to be issued when we specify __GFP_NOWARN, but > currently in paths like alloc_pages() and kmalloc(), there are still > some warnings printed, fix it. Hi Andrew, Maybe we only need to deal with memory allocation failures, such as should_fail() (This leads to deadlock in PATCH[2/2]). These WARN_ON_ONCE()s report usage problems and should not be printed. If they are printed, we should fix these usage problems. Thanks, Qi > > Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> > --- > include/linux/fault-inject.h | 2 ++ > lib/fault-inject.c | 3 +++ > mm/failslab.c | 3 +++ > mm/internal.h | 11 +++++++++++ > mm/page_alloc.c | 22 ++++++++++++---------- > 5 files changed, 31 insertions(+), 10 deletions(-) > > diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h > index 2d04f6448cde..9f6e25467844 100644 > --- a/include/linux/fault-inject.h > +++ b/include/linux/fault-inject.h > @@ -20,6 +20,7 @@ struct fault_attr { > atomic_t space; > unsigned long verbose; > bool task_filter; > + bool no_warn; > unsigned long stacktrace_depth; > unsigned long require_start; > unsigned long require_end; > @@ -39,6 +40,7 @@ struct fault_attr { > .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED, \ > .verbose = 2, \ > .dname = NULL, \ > + .no_warn = false, \ > } > > #define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER > diff --git a/lib/fault-inject.c b/lib/fault-inject.c > index ce12621b4275..423784d9c058 100644 > --- a/lib/fault-inject.c > +++ b/lib/fault-inject.c > @@ -41,6 +41,9 @@ EXPORT_SYMBOL_GPL(setup_fault_attr); > > static void fail_dump(struct fault_attr *attr) > { > + if (attr->no_warn) > + return; > + > if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) { > printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n" > "name %pd, interval %lu, probability %lu, " > diff --git a/mm/failslab.c b/mm/failslab.c > index f92fed91ac23..58df9789f1d2 100644 > --- a/mm/failslab.c > +++ b/mm/failslab.c > @@ -30,6 +30,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags) > if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB)) > return false; > > + if (gfpflags & __GFP_NOWARN) > + failslab.attr.no_warn = true; > + > return should_fail(&failslab.attr, s->object_size); > } > > diff --git a/mm/internal.h b/mm/internal.h > index cf16280ce132..7a268fac6559 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -35,6 +35,17 @@ struct folio_batch; > /* Do not use these with a slab allocator */ > #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) > > +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ > + static bool __section(".data.once") __warned; \ > + int __ret_warn_once = !!(cond); \ > + \ > + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ > + __warned = true; \ > + WARN_ON(1); \ > + } \ > + unlikely(__ret_warn_once); \ > +}) > + > void page_writeback_init(void); > > static inline void *folio_raw_mapping(struct folio *folio) > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 0e42038382c1..2bf4ce4d0e2f 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -3722,7 +3722,7 @@ struct page *rmqueue(struct zone *preferred_zone, > * We most definitely don't want callers attempting to > * allocate greater than order-1 page units with __GFP_NOFAIL. > */ > - WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); > + WARN_ON_ONCE_GFP((gfp_flags & __GFP_NOFAIL) && (order > 1), gfp_flags); > > do { > page = NULL; > @@ -3799,6 +3799,9 @@ static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) > (gfp_mask & __GFP_DIRECT_RECLAIM)) > return false; > > + if (gfp_mask & __GFP_NOWARN) > + fail_page_alloc.attr.no_warn = true; > + > return should_fail(&fail_page_alloc.attr, 1 << order); > } > > @@ -4346,7 +4349,8 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, > */ > > /* Exhausted what can be done so it's blame time */ > - if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { > + if (out_of_memory(&oc) || > + WARN_ON_ONCE_GFP(gfp_mask & __GFP_NOFAIL, gfp_mask)) { > *did_some_progress = 1; > > /* > @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > * We also sanity check to catch abuse of atomic reserves being used by > * callers that are not in atomic context. > */ > - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) > + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == > + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) > gfp_mask &= ~__GFP_ATOMIC; > > retry_cpuset: > @@ -5117,7 +5121,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > * All existing users of the __GFP_NOFAIL are blockable, so warn > * of any new users that actually require GFP_NOWAIT > */ > - if (WARN_ON_ONCE(!can_direct_reclaim)) > + if (WARN_ON_ONCE_GFP(!can_direct_reclaim, gfp_mask)) > goto fail; > > /* > @@ -5125,7 +5129,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > * because we cannot reclaim anything and only can loop waiting > * for somebody to do a work for us > */ > - WARN_ON_ONCE(current->flags & PF_MEMALLOC); > + WARN_ON_ONCE_GFP(current->flags & PF_MEMALLOC, gfp_mask); > > /* > * non failing costly orders are a hard requirement which we > @@ -5133,7 +5137,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > * so that we can identify them and convert them to something > * else. > */ > - WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); > + WARN_ON_ONCE_GFP(order > PAGE_ALLOC_COSTLY_ORDER, gfp_mask); > > /* > * Help non-failing allocations by giving them access to memory > @@ -5379,10 +5383,8 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, > * There are several places where we assume that the order value is sane > * so bail out early if the request is out of bound. > */ > - if (unlikely(order >= MAX_ORDER)) { > - WARN_ON_ONCE(!(gfp & __GFP_NOWARN)); > + if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) > return NULL; > - } > > gfp &= gfp_allowed_mask; > /*
On 2022/5/11 1:12 PM, Qi Zheng wrote: > > > On 2022/5/10 7:38 PM, Qi Zheng wrote: >> We expect no warnings to be issued when we specify __GFP_NOWARN, but >> currently in paths like alloc_pages() and kmalloc(), there are still >> some warnings printed, fix it. > > Hi Andrew, > > Maybe we only need to deal with memory allocation failures, such as > should_fail() (This leads to deadlock in PATCH[2/2]). These > WARN_ON_ONCE()s report usage problems and should not be printed. If they such as WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1), gfp_flags). > are printed, we should fix these usage problems. > > Thanks, > Qi > > >> >> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> >> --- >> include/linux/fault-inject.h | 2 ++ >> lib/fault-inject.c | 3 +++ >> mm/failslab.c | 3 +++ >> mm/internal.h | 11 +++++++++++ >> mm/page_alloc.c | 22 ++++++++++++---------- >> 5 files changed, 31 insertions(+), 10 deletions(-) >> >> diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h >> index 2d04f6448cde..9f6e25467844 100644 >> --- a/include/linux/fault-inject.h >> +++ b/include/linux/fault-inject.h >> @@ -20,6 +20,7 @@ struct fault_attr { >> atomic_t space; >> unsigned long verbose; >> bool task_filter; >> + bool no_warn; >> unsigned long stacktrace_depth; >> unsigned long require_start; >> unsigned long require_end; >> @@ -39,6 +40,7 @@ struct fault_attr { >> .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED, \ >> .verbose = 2, \ >> .dname = NULL, \ >> + .no_warn = false, \ >> } >> #define DECLARE_FAULT_ATTR(name) struct fault_attr name = >> FAULT_ATTR_INITIALIZER >> diff --git a/lib/fault-inject.c b/lib/fault-inject.c >> index ce12621b4275..423784d9c058 100644 >> --- a/lib/fault-inject.c >> +++ b/lib/fault-inject.c >> @@ -41,6 +41,9 @@ EXPORT_SYMBOL_GPL(setup_fault_attr); >> static void fail_dump(struct fault_attr *attr) >> { >> + if (attr->no_warn) >> + return; >> + >> if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) { >> printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n" >> "name %pd, interval %lu, probability %lu, " >> diff --git a/mm/failslab.c b/mm/failslab.c >> index f92fed91ac23..58df9789f1d2 100644 >> --- a/mm/failslab.c >> +++ b/mm/failslab.c >> @@ -30,6 +30,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t >> gfpflags) >> if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB)) >> return false; >> + if (gfpflags & __GFP_NOWARN) >> + failslab.attr.no_warn = true; >> + >> return should_fail(&failslab.attr, s->object_size); >> } >> diff --git a/mm/internal.h b/mm/internal.h >> index cf16280ce132..7a268fac6559 100644 >> --- a/mm/internal.h >> +++ b/mm/internal.h >> @@ -35,6 +35,17 @@ struct folio_batch; >> /* Do not use these with a slab allocator */ >> #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) >> +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ >> + static bool __section(".data.once") __warned; \ >> + int __ret_warn_once = !!(cond); \ >> + \ >> + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && >> !__warned)) { \ >> + __warned = true; \ >> + WARN_ON(1); \ >> + } \ >> + unlikely(__ret_warn_once); \ >> +}) >> + >> void page_writeback_init(void); >> static inline void *folio_raw_mapping(struct folio *folio) >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 0e42038382c1..2bf4ce4d0e2f 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -3722,7 +3722,7 @@ struct page *rmqueue(struct zone *preferred_zone, >> * We most definitely don't want callers attempting to >> * allocate greater than order-1 page units with __GFP_NOFAIL. >> */ >> - WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); >> + WARN_ON_ONCE_GFP((gfp_flags & __GFP_NOFAIL) && (order > 1), >> gfp_flags); >> do { >> page = NULL; >> @@ -3799,6 +3799,9 @@ static bool __should_fail_alloc_page(gfp_t >> gfp_mask, unsigned int order) >> (gfp_mask & __GFP_DIRECT_RECLAIM)) >> return false; >> + if (gfp_mask & __GFP_NOWARN) >> + fail_page_alloc.attr.no_warn = true; >> + >> return should_fail(&fail_page_alloc.attr, 1 << order); >> } >> @@ -4346,7 +4349,8 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned >> int order, >> */ >> /* Exhausted what can be done so it's blame time */ >> - if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { >> + if (out_of_memory(&oc) || >> + WARN_ON_ONCE_GFP(gfp_mask & __GFP_NOFAIL, gfp_mask)) { >> *did_some_progress = 1; >> /* >> @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned >> int order, >> * We also sanity check to catch abuse of atomic reserves being >> used by >> * callers that are not in atomic context. >> */ >> - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >> - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) >> + if (WARN_ON_ONCE_GFP((gfp_mask & >> (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == >> + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) >> gfp_mask &= ~__GFP_ATOMIC; >> retry_cpuset: >> @@ -5117,7 +5121,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned >> int order, >> * All existing users of the __GFP_NOFAIL are blockable, so >> warn >> * of any new users that actually require GFP_NOWAIT >> */ >> - if (WARN_ON_ONCE(!can_direct_reclaim)) >> + if (WARN_ON_ONCE_GFP(!can_direct_reclaim, gfp_mask)) >> goto fail; >> /* >> @@ -5125,7 +5129,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned >> int order, >> * because we cannot reclaim anything and only can loop waiting >> * for somebody to do a work for us >> */ >> - WARN_ON_ONCE(current->flags & PF_MEMALLOC); >> + WARN_ON_ONCE_GFP(current->flags & PF_MEMALLOC, gfp_mask); >> /* >> * non failing costly orders are a hard requirement which we >> @@ -5133,7 +5137,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned >> int order, >> * so that we can identify them and convert them to something >> * else. >> */ >> - WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); >> + WARN_ON_ONCE_GFP(order > PAGE_ALLOC_COSTLY_ORDER, gfp_mask); >> /* >> * Help non-failing allocations by giving them access to memory >> @@ -5379,10 +5383,8 @@ struct page *__alloc_pages(gfp_t gfp, unsigned >> int order, int preferred_nid, >> * There are several places where we assume that the order value >> is sane >> * so bail out early if the request is out of bound. >> */ >> - if (unlikely(order >= MAX_ORDER)) { >> - WARN_ON_ONCE(!(gfp & __GFP_NOWARN)); >> + if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) >> return NULL; >> - } >> gfp &= gfp_allowed_mask; >> /* >
diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index 2d04f6448cde..9f6e25467844 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -20,6 +20,7 @@ struct fault_attr { atomic_t space; unsigned long verbose; bool task_filter; + bool no_warn; unsigned long stacktrace_depth; unsigned long require_start; unsigned long require_end; @@ -39,6 +40,7 @@ struct fault_attr { .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED, \ .verbose = 2, \ .dname = NULL, \ + .no_warn = false, \ } #define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER diff --git a/lib/fault-inject.c b/lib/fault-inject.c index ce12621b4275..423784d9c058 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -41,6 +41,9 @@ EXPORT_SYMBOL_GPL(setup_fault_attr); static void fail_dump(struct fault_attr *attr) { + if (attr->no_warn) + return; + if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) { printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n" "name %pd, interval %lu, probability %lu, " diff --git a/mm/failslab.c b/mm/failslab.c index f92fed91ac23..58df9789f1d2 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -30,6 +30,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags) if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB)) return false; + if (gfpflags & __GFP_NOWARN) + failslab.attr.no_warn = true; + return should_fail(&failslab.attr, s->object_size); } diff --git a/mm/internal.h b/mm/internal.h index cf16280ce132..7a268fac6559 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -35,6 +35,17 @@ struct folio_batch; /* Do not use these with a slab allocator */ #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ + static bool __section(".data.once") __warned; \ + int __ret_warn_once = !!(cond); \ + \ + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ + __warned = true; \ + WARN_ON(1); \ + } \ + unlikely(__ret_warn_once); \ +}) + void page_writeback_init(void); static inline void *folio_raw_mapping(struct folio *folio) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0e42038382c1..2bf4ce4d0e2f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3722,7 +3722,7 @@ struct page *rmqueue(struct zone *preferred_zone, * We most definitely don't want callers attempting to * allocate greater than order-1 page units with __GFP_NOFAIL. */ - WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); + WARN_ON_ONCE_GFP((gfp_flags & __GFP_NOFAIL) && (order > 1), gfp_flags); do { page = NULL; @@ -3799,6 +3799,9 @@ static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) (gfp_mask & __GFP_DIRECT_RECLAIM)) return false; + if (gfp_mask & __GFP_NOWARN) + fail_page_alloc.attr.no_warn = true; + return should_fail(&fail_page_alloc.attr, 1 << order); } @@ -4346,7 +4349,8 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, */ /* Exhausted what can be done so it's blame time */ - if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { + if (out_of_memory(&oc) || + WARN_ON_ONCE_GFP(gfp_mask & __GFP_NOFAIL, gfp_mask)) { *did_some_progress = 1; /* @@ -4902,8 +4906,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * We also sanity check to catch abuse of atomic reserves being used by * callers that are not in atomic context. */ - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) + if (WARN_ON_ONCE_GFP((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == + (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM), gfp_mask)) gfp_mask &= ~__GFP_ATOMIC; retry_cpuset: @@ -5117,7 +5121,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * All existing users of the __GFP_NOFAIL are blockable, so warn * of any new users that actually require GFP_NOWAIT */ - if (WARN_ON_ONCE(!can_direct_reclaim)) + if (WARN_ON_ONCE_GFP(!can_direct_reclaim, gfp_mask)) goto fail; /* @@ -5125,7 +5129,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * because we cannot reclaim anything and only can loop waiting * for somebody to do a work for us */ - WARN_ON_ONCE(current->flags & PF_MEMALLOC); + WARN_ON_ONCE_GFP(current->flags & PF_MEMALLOC, gfp_mask); /* * non failing costly orders are a hard requirement which we @@ -5133,7 +5137,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * so that we can identify them and convert them to something * else. */ - WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); + WARN_ON_ONCE_GFP(order > PAGE_ALLOC_COSTLY_ORDER, gfp_mask); /* * Help non-failing allocations by giving them access to memory @@ -5379,10 +5383,8 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, * There are several places where we assume that the order value is sane * so bail out early if the request is out of bound. */ - if (unlikely(order >= MAX_ORDER)) { - WARN_ON_ONCE(!(gfp & __GFP_NOWARN)); + if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) return NULL; - } gfp &= gfp_allowed_mask; /*
We expect no warnings to be issued when we specify __GFP_NOWARN, but currently in paths like alloc_pages() and kmalloc(), there are still some warnings printed, fix it. Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> --- include/linux/fault-inject.h | 2 ++ lib/fault-inject.c | 3 +++ mm/failslab.c | 3 +++ mm/internal.h | 11 +++++++++++ mm/page_alloc.c | 22 ++++++++++++---------- 5 files changed, 31 insertions(+), 10 deletions(-)