[PATCH v2] mm: remove redundant __GFP_NOWARN

[PATCH v2] mm: remove redundant __GFP_NOWARN

[Qianfeng Rong]

Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
GFP_NOWAIT implicitly include __GFP_NOWARN.

Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
`GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
redundant flags across subsystems.

No functional changes.

Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
---
v1->v2:
- Added a modification to remove redundant __GFP_NOWARN in
  mm/damon/ops-common.c
---
 mm/damon/ops-common.c | 2 +-
 mm/filemap.c          | 2 +-
 mm/mmu_gather.c       | 4 ++--
 mm/rmap.c             | 2 +-
 mm/vmalloc.c          | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
index 99321ff5cb92..b43595730f08 100644
--- a/mm/damon/ops-common.c
+++ b/mm/damon/ops-common.c
@@ -303,7 +303,7 @@ static unsigned int __damon_migrate_folio_list(
 		 * instead of migrated.
 		 */
 		.gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) |
-			__GFP_NOWARN | __GFP_NOMEMALLOC | GFP_NOWAIT,
+			__GFP_NOMEMALLOC | GFP_NOWAIT,
 		.nid = target_nid,
 	};
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 4e5c9544fee4..c21e98657e0b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1961,7 +1961,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index,
 			gfp &= ~__GFP_FS;
 		if (fgp_flags & FGP_NOWAIT) {
 			gfp &= ~GFP_KERNEL;
-			gfp |= GFP_NOWAIT | __GFP_NOWARN;
+			gfp |= GFP_NOWAIT;
 		}
 		if (WARN_ON_ONCE(!(fgp_flags & (FGP_LOCK | FGP_FOR_MMAP))))
 			fgp_flags |= FGP_LOCK;
diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
index b49cc6385f1f..374aa6f021c6 100644
--- a/mm/mmu_gather.c
+++ b/mm/mmu_gather.c
@@ -32,7 +32,7 @@ static bool tlb_next_batch(struct mmu_gather *tlb)
 	if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
 		return false;
 
-	batch = (void *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
+	batch = (void *)__get_free_page(GFP_NOWAIT);
 	if (!batch)
 		return false;
 
@@ -364,7 +364,7 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
 	struct mmu_table_batch **batch = &tlb->batch;
 
 	if (*batch == NULL) {
-		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
+		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT);
 		if (*batch == NULL) {
 			tlb_table_invalidate(tlb);
 			tlb_remove_table_one(table);
diff --git a/mm/rmap.c b/mm/rmap.c
index 568198e9efc2..7baa7385e1ce 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -285,7 +285,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
 	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
 		struct anon_vma *anon_vma;
 
-		avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN);
+		avc = anon_vma_chain_alloc(GFP_NOWAIT);
 		if (unlikely(!avc)) {
 			unlock_anon_vma_root(root);
 			root = NULL;
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6dbcdceecae1..90c3de1a0417 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -5177,7 +5177,7 @@ static void vmap_init_nodes(void)
 	int n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
 
 	if (n > 1) {
-		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
+		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT);
 		if (vn) {
 			/* Node partition is 16 pages. */
 			vmap_zone_size = (1 << 4) * PAGE_SIZE;
-- 
2.34.1

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Liam R. Howlett]

* Qianfeng Rong <rongqianfeng@vivo.com> [250812 09:52]:
> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> GFP_NOWAIT implicitly include __GFP_NOWARN.
> 
> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> redundant flags across subsystems.
> 
> No functional changes.
> 
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
> v1->v2:
> - Added a modification to remove redundant __GFP_NOWARN in
>   mm/damon/ops-common.c
> ---
>  mm/damon/ops-common.c | 2 +-
>  mm/filemap.c          | 2 +-
>  mm/mmu_gather.c       | 4 ++--
>  mm/rmap.c             | 2 +-
>  mm/vmalloc.c          | 2 +-
>  5 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
> index 99321ff5cb92..b43595730f08 100644
> --- a/mm/damon/ops-common.c
> +++ b/mm/damon/ops-common.c
> @@ -303,7 +303,7 @@ static unsigned int __damon_migrate_folio_list(
>  		 * instead of migrated.
>  		 */
>  		.gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) |
> -			__GFP_NOWARN | __GFP_NOMEMALLOC | GFP_NOWAIT,
> +			__GFP_NOMEMALLOC | GFP_NOWAIT,
>  		.nid = target_nid,
>  	};
>  
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 4e5c9544fee4..c21e98657e0b 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -1961,7 +1961,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index,
>  			gfp &= ~__GFP_FS;
>  		if (fgp_flags & FGP_NOWAIT) {
>  			gfp &= ~GFP_KERNEL;
> -			gfp |= GFP_NOWAIT | __GFP_NOWARN;
> +			gfp |= GFP_NOWAIT;
>  		}
>  		if (WARN_ON_ONCE(!(fgp_flags & (FGP_LOCK | FGP_FOR_MMAP))))
>  			fgp_flags |= FGP_LOCK;
> diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
> index b49cc6385f1f..374aa6f021c6 100644
> --- a/mm/mmu_gather.c
> +++ b/mm/mmu_gather.c
> @@ -32,7 +32,7 @@ static bool tlb_next_batch(struct mmu_gather *tlb)
>  	if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
>  		return false;
>  
> -	batch = (void *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> +	batch = (void *)__get_free_page(GFP_NOWAIT);
>  	if (!batch)
>  		return false;
>  
> @@ -364,7 +364,7 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
>  	struct mmu_table_batch **batch = &tlb->batch;
>  
>  	if (*batch == NULL) {
> -		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> +		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT);
>  		if (*batch == NULL) {
>  			tlb_table_invalidate(tlb);
>  			tlb_remove_table_one(table);
> diff --git a/mm/rmap.c b/mm/rmap.c
> index 568198e9efc2..7baa7385e1ce 100644
> --- a/mm/rmap.c
> +++ b/mm/rmap.c
> @@ -285,7 +285,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
>  	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
>  		struct anon_vma *anon_vma;
>  
> -		avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN);
> +		avc = anon_vma_chain_alloc(GFP_NOWAIT);
>  		if (unlikely(!avc)) {
>  			unlock_anon_vma_root(root);
>  			root = NULL;
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 6dbcdceecae1..90c3de1a0417 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -5177,7 +5177,7 @@ static void vmap_init_nodes(void)
>  	int n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
>  
>  	if (n > 1) {
> -		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
> +		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT);
>  		if (vn) {
>  			/* Node partition is 16 pages. */
>  			vmap_zone_size = (1 << 4) * PAGE_SIZE;
> -- 
> 2.34.1
> 

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Lorenzo Stoakes]

On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> GFP_NOWAIT implicitly include __GFP_NOWARN.
>
> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> redundant flags across subsystems.
>
> No functional changes.
>
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>

LGTM, I wonder if there are other such redundancies in the kernel?

Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

> ---
> v1->v2:
> - Added a modification to remove redundant __GFP_NOWARN in
>   mm/damon/ops-common.c
> ---
>  mm/damon/ops-common.c | 2 +-
>  mm/filemap.c          | 2 +-
>  mm/mmu_gather.c       | 4 ++--
>  mm/rmap.c             | 2 +-
>  mm/vmalloc.c          | 2 +-
>  5 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
> index 99321ff5cb92..b43595730f08 100644
> --- a/mm/damon/ops-common.c
> +++ b/mm/damon/ops-common.c
> @@ -303,7 +303,7 @@ static unsigned int __damon_migrate_folio_list(
>  		 * instead of migrated.
>  		 */
>  		.gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) |
> -			__GFP_NOWARN | __GFP_NOMEMALLOC | GFP_NOWAIT,
> +			__GFP_NOMEMALLOC | GFP_NOWAIT,
>  		.nid = target_nid,
>  	};
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 4e5c9544fee4..c21e98657e0b 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -1961,7 +1961,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index,
>  			gfp &= ~__GFP_FS;
>  		if (fgp_flags & FGP_NOWAIT) {
>  			gfp &= ~GFP_KERNEL;
> -			gfp |= GFP_NOWAIT | __GFP_NOWARN;
> +			gfp |= GFP_NOWAIT;
>  		}
>  		if (WARN_ON_ONCE(!(fgp_flags & (FGP_LOCK | FGP_FOR_MMAP))))
>  			fgp_flags |= FGP_LOCK;
> diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
> index b49cc6385f1f..374aa6f021c6 100644
> --- a/mm/mmu_gather.c
> +++ b/mm/mmu_gather.c
> @@ -32,7 +32,7 @@ static bool tlb_next_batch(struct mmu_gather *tlb)
>  	if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
>  		return false;
>
> -	batch = (void *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> +	batch = (void *)__get_free_page(GFP_NOWAIT);
>  	if (!batch)
>  		return false;
>
> @@ -364,7 +364,7 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
>  	struct mmu_table_batch **batch = &tlb->batch;
>
>  	if (*batch == NULL) {
> -		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> +		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT);
>  		if (*batch == NULL) {
>  			tlb_table_invalidate(tlb);
>  			tlb_remove_table_one(table);
> diff --git a/mm/rmap.c b/mm/rmap.c
> index 568198e9efc2..7baa7385e1ce 100644
> --- a/mm/rmap.c
> +++ b/mm/rmap.c
> @@ -285,7 +285,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
>  	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
>  		struct anon_vma *anon_vma;
>
> -		avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN);
> +		avc = anon_vma_chain_alloc(GFP_NOWAIT);
>  		if (unlikely(!avc)) {
>  			unlock_anon_vma_root(root);
>  			root = NULL;
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 6dbcdceecae1..90c3de1a0417 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -5177,7 +5177,7 @@ static void vmap_init_nodes(void)
>  	int n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
>
>  	if (n > 1) {
> -		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
> +		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT);
>  		if (vn) {
>  			/* Node partition is 16 pages. */
>  			vmap_zone_size = (1 << 4) * PAGE_SIZE;
> --
> 2.34.1
>

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Vishal Moola (Oracle)]

On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> GFP_NOWAIT implicitly include __GFP_NOWARN.
> 
> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> redundant flags across subsystems.
> 
> No functional changes.
> 
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>

Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Vishal Moola (Oracle)]

On Tue, Aug 12, 2025 at 05:46:47PM +0100, Lorenzo Stoakes wrote:
> On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
> > Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> > GFP_NOWAIT implicitly include __GFP_NOWARN.
> >
> > Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> > `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> > redundant flags across subsystems.
> >
> > No functional changes.
> >
> > Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> > Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
> 
> LGTM, I wonder if there are other such redundancies in the kernel?

Looks like theres a lot left for this specific case. At least 48 show up
that are spread out across subsystems when running 'git grep
"GFP_NOWAIT.*GFP_NOWARN"'.

I think they should be cleaned up in sets per-subsystem to minimize
merge conflicts, as suggested in the commit mentioned above (16f5dfbc851b).

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Uladzislau Rezki]

On Tue, Aug 12, 2025 at 05:46:47PM +0100, Lorenzo Stoakes wrote:
> On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
> > Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> > GFP_NOWAIT implicitly include __GFP_NOWARN.
> >
> > Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> > `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> > redundant flags across subsystems.
> >
> > No functional changes.
> >
> > Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> > Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
> 
> LGTM, I wonder if there are other such redundancies in the kernel?
> 
> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
> 
> > ---
> > v1->v2:
> > - Added a modification to remove redundant __GFP_NOWARN in
> >   mm/damon/ops-common.c
> > ---
> >  mm/damon/ops-common.c | 2 +-
> >  mm/filemap.c          | 2 +-
> >  mm/mmu_gather.c       | 4 ++--
> >  mm/rmap.c             | 2 +-
> >  mm/vmalloc.c          | 2 +-
> >  5 files changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
> > index 99321ff5cb92..b43595730f08 100644
> > --- a/mm/damon/ops-common.c
> > +++ b/mm/damon/ops-common.c
> > @@ -303,7 +303,7 @@ static unsigned int __damon_migrate_folio_list(
> >  		 * instead of migrated.
> >  		 */
> >  		.gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) |
> > -			__GFP_NOWARN | __GFP_NOMEMALLOC | GFP_NOWAIT,
> > +			__GFP_NOMEMALLOC | GFP_NOWAIT,
> >  		.nid = target_nid,
> >  	};
> >
> > diff --git a/mm/filemap.c b/mm/filemap.c
> > index 4e5c9544fee4..c21e98657e0b 100644
> > --- a/mm/filemap.c
> > +++ b/mm/filemap.c
> > @@ -1961,7 +1961,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index,
> >  			gfp &= ~__GFP_FS;
> >  		if (fgp_flags & FGP_NOWAIT) {
> >  			gfp &= ~GFP_KERNEL;
> > -			gfp |= GFP_NOWAIT | __GFP_NOWARN;
> > +			gfp |= GFP_NOWAIT;
> >  		}
> >  		if (WARN_ON_ONCE(!(fgp_flags & (FGP_LOCK | FGP_FOR_MMAP))))
> >  			fgp_flags |= FGP_LOCK;
> > diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
> > index b49cc6385f1f..374aa6f021c6 100644
> > --- a/mm/mmu_gather.c
> > +++ b/mm/mmu_gather.c
> > @@ -32,7 +32,7 @@ static bool tlb_next_batch(struct mmu_gather *tlb)
> >  	if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
> >  		return false;
> >
> > -	batch = (void *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> > +	batch = (void *)__get_free_page(GFP_NOWAIT);
> >  	if (!batch)
> >  		return false;
> >
> > @@ -364,7 +364,7 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
> >  	struct mmu_table_batch **batch = &tlb->batch;
> >
> >  	if (*batch == NULL) {
> > -		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
> > +		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT);
> >  		if (*batch == NULL) {
> >  			tlb_table_invalidate(tlb);
> >  			tlb_remove_table_one(table);
> > diff --git a/mm/rmap.c b/mm/rmap.c
> > index 568198e9efc2..7baa7385e1ce 100644
> > --- a/mm/rmap.c
> > +++ b/mm/rmap.c
> > @@ -285,7 +285,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
> >  	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
> >  		struct anon_vma *anon_vma;
> >
> > -		avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN);
> > +		avc = anon_vma_chain_alloc(GFP_NOWAIT);
> >  		if (unlikely(!avc)) {
> >  			unlock_anon_vma_root(root);
> >  			root = NULL;
> > diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> > index 6dbcdceecae1..90c3de1a0417 100644
> > --- a/mm/vmalloc.c
> > +++ b/mm/vmalloc.c
> > @@ -5177,7 +5177,7 @@ static void vmap_init_nodes(void)
> >  	int n = clamp_t(unsigned int, num_possible_cpus(), 1, 128);
> >
> >  	if (n > 1) {
> > -		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT | __GFP_NOWARN);
> > +		vn = kmalloc_array(n, sizeof(*vn), GFP_NOWAIT);
> >  		if (vn) {
> >  			/* Node partition is 16 pages. */
> >  			vmap_zone_size = (1 << 4) * PAGE_SIZE;
> > --
> > 2.34.1
> >
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>

--
Uladzislau Rezki

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[SeongJae Park]

On Tue, 12 Aug 2025 21:52:25 +0800 Qianfeng Rong <rongqianfeng@vivo.com> wrote:

> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> GFP_NOWAIT implicitly include __GFP_NOWARN.
> 
> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> redundant flags across subsystems.
> 
> No functional changes.
> 
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>

Reviewed-by: SeongJae Park <sj@kernel.org>


Thanks,
SJ

[...]

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[David Hildenbrand]

On 12.08.25 15:52, Qianfeng Rong wrote:
> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
> GFP_NOWAIT implicitly include __GFP_NOWARN.
> 
> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
> redundant flags across subsystems.
> 
> No functional changes.
> 
> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
> ---

Acked-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Qianfeng Rong]

在 2025/8/13 0:46, Lorenzo Stoakes 写道:
> On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
>> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
>> GFP_NOWAIT implicitly include __GFP_NOWARN.
>>
>> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
>> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
>> redundant flags across subsystems.
>>
>> No functional changes.
>>
>> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
>> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
> LGTM, I wonder if there are other such redundancies in the kernel?
For similar redundancies in other subsystems, I submitted separate patches
to minimize potential merge conflicts.

Best regards,
Qianfeng
>
> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
>
>

Re: [PATCH v2] mm: remove redundant __GFP_NOWARN

[Qianfeng Rong]

在 2025/8/13 1:55, Vishal Moola (Oracle) 写道:
> [You don't often get email from vishal.moola@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> On Tue, Aug 12, 2025 at 05:46:47PM +0100, Lorenzo Stoakes wrote:
>> On Tue, Aug 12, 2025 at 09:52:25PM +0800, Qianfeng Rong wrote:
>>> Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
>>> GFP_NOWAIT implicitly include __GFP_NOWARN.
>>>
>>> Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
>>> `GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
>>> redundant flags across subsystems.
>>>
>>> No functional changes.
>>>
>>> Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
>>> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
>> LGTM, I wonder if there are other such redundancies in the kernel?
> Looks like theres a lot left for this specific case. At least 48 show up
> that are spread out across subsystems when running 'git grep
> "GFP_NOWAIT.*GFP_NOWARN"'.
>
> I think they should be cleaned up in sets per-subsystem to minimize
> merge conflicts, as suggested in the commit mentioned above (16f5dfbc851b).

I agree. I submitted similar patches for each subsystem separately.
It may take some time to see the code merged into the next branch.

Best regards,
Qianfeng