diff mbox series

[v2,06/39] mm: enumerate all gfp flags

Message ID 20231024134637.3120277-7-surenb@google.com (mailing list archive)
State New, archived
Headers show
Series Memory allocation profiling | expand

Commit Message

Suren Baghdasaryan Oct. 24, 2023, 1:46 p.m. UTC
Introduce GFP bits enumeration to let compiler track the number of used
bits (which depends on the config options) instead of hardcoding them.
That simplifies __GFP_BITS_SHIFT calculation.

Suggested-by: Petr Tesařík <petr@tesarici.cz>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 include/linux/gfp_types.h | 90 +++++++++++++++++++++++++++------------
 1 file changed, 62 insertions(+), 28 deletions(-)

Comments

Petr Tesařík Oct. 25, 2023, 5:46 a.m. UTC | #1
On Tue, 24 Oct 2023 06:46:03 -0700
Suren Baghdasaryan <surenb@google.com> wrote:

> Introduce GFP bits enumeration to let compiler track the number of used
> bits (which depends on the config options) instead of hardcoding them.
> That simplifies __GFP_BITS_SHIFT calculation.
> Suggested-by: Petr Tesařík <petr@tesarici.cz>
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> ---
>  include/linux/gfp_types.h | 90 +++++++++++++++++++++++++++------------
>  1 file changed, 62 insertions(+), 28 deletions(-)
> 
> diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
> index 6583a58670c5..3fbe624763d9 100644
> --- a/include/linux/gfp_types.h
> +++ b/include/linux/gfp_types.h
> @@ -21,44 +21,78 @@ typedef unsigned int __bitwise gfp_t;
>   * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
>   */
>  
> +enum {
> +	___GFP_DMA_BIT,
> +	___GFP_HIGHMEM_BIT,
> +	___GFP_DMA32_BIT,
> +	___GFP_MOVABLE_BIT,
> +	___GFP_RECLAIMABLE_BIT,
> +	___GFP_HIGH_BIT,
> +	___GFP_IO_BIT,
> +	___GFP_FS_BIT,
> +	___GFP_ZERO_BIT,
> +	___GFP_UNUSED_BIT,	/* 0x200u unused */
> +	___GFP_DIRECT_RECLAIM_BIT,
> +	___GFP_KSWAPD_RECLAIM_BIT,
> +	___GFP_WRITE_BIT,
> +	___GFP_NOWARN_BIT,
> +	___GFP_RETRY_MAYFAIL_BIT,
> +	___GFP_NOFAIL_BIT,
> +	___GFP_NORETRY_BIT,
> +	___GFP_MEMALLOC_BIT,
> +	___GFP_COMP_BIT,
> +	___GFP_NOMEMALLOC_BIT,
> +	___GFP_HARDWALL_BIT,
> +	___GFP_THISNODE_BIT,
> +	___GFP_ACCOUNT_BIT,
> +	___GFP_ZEROTAGS_BIT,
> +#ifdef CONFIG_KASAN_HW_TAGS
> +	___GFP_SKIP_ZERO_BIT,
> +	___GFP_SKIP_KASAN_BIT,
> +#endif
> +#ifdef CONFIG_LOCKDEP
> +	___GFP_NOLOCKDEP_BIT,
> +#endif
> +	___GFP_LAST_BIT
> +};
> +
>  /* Plain integer GFP bitmasks. Do not use this directly. */
> -#define ___GFP_DMA		0x01u
> -#define ___GFP_HIGHMEM		0x02u
> -#define ___GFP_DMA32		0x04u
> -#define ___GFP_MOVABLE		0x08u
> -#define ___GFP_RECLAIMABLE	0x10u
> -#define ___GFP_HIGH		0x20u
> -#define ___GFP_IO		0x40u
> -#define ___GFP_FS		0x80u
> -#define ___GFP_ZERO		0x100u
> +#define ___GFP_DMA		BIT(___GFP_DMA_BIT)
> +#define ___GFP_HIGHMEM		BIT(___GFP_HIGHMEM_BIT)
> +#define ___GFP_DMA32		BIT(___GFP_DMA32_BIT)
> +#define ___GFP_MOVABLE		BIT(___GFP_MOVABLE_BIT)
> +#define ___GFP_RECLAIMABLE	BIT(___GFP_RECLAIMABLE_BIT)
> +#define ___GFP_HIGH		BIT(___GFP_HIGH_BIT)
> +#define ___GFP_IO		BIT(___GFP_IO_BIT)
> +#define ___GFP_FS		BIT(___GFP_FS_BIT)
> +#define ___GFP_ZERO		BIT(___GFP_ZERO_BIT)
>  /* 0x200u unused */

This comment can be also removed here, because it is already stated
above with the definition of ___GFP_UNUSED_BIT.

Then again, I think that the GFP bits have never been compacted after
Neil Brown removed __GFP_ATOMIC with commit 2973d8229b78 simply because
that would mean changing definitions of all subsequent GFP flags. FWIW
I am not aware of any code that would depend on the numeric value of
___GFP_* macros, so this patch seems like a good opportunity to change
the numbering and get rid of this unused 0x200u altogether.

@Neil: I have added you to the conversation in case you want to correct
my understanding of the unused bit.

Other than that LGTM.

Petr T

> -#define ___GFP_DIRECT_RECLAIM	0x400u
> -#define ___GFP_KSWAPD_RECLAIM	0x800u
> -#define ___GFP_WRITE		0x1000u
> -#define ___GFP_NOWARN		0x2000u
> -#define ___GFP_RETRY_MAYFAIL	0x4000u
> -#define ___GFP_NOFAIL		0x8000u
> -#define ___GFP_NORETRY		0x10000u
> -#define ___GFP_MEMALLOC		0x20000u
> -#define ___GFP_COMP		0x40000u
> -#define ___GFP_NOMEMALLOC	0x80000u
> -#define ___GFP_HARDWALL		0x100000u
> -#define ___GFP_THISNODE		0x200000u
> -#define ___GFP_ACCOUNT		0x400000u
> -#define ___GFP_ZEROTAGS		0x800000u
> +#define ___GFP_DIRECT_RECLAIM	BIT(___GFP_DIRECT_RECLAIM_BIT)
> +#define ___GFP_KSWAPD_RECLAIM	BIT(___GFP_KSWAPD_RECLAIM_BIT)
> +#define ___GFP_WRITE		BIT(___GFP_WRITE_BIT)
> +#define ___GFP_NOWARN		BIT(___GFP_NOWARN_BIT)
> +#define ___GFP_RETRY_MAYFAIL	BIT(___GFP_RETRY_MAYFAIL_BIT)
> +#define ___GFP_NOFAIL		BIT(___GFP_NOFAIL_BIT)
> +#define ___GFP_NORETRY		BIT(___GFP_NORETRY_BIT)
> +#define ___GFP_MEMALLOC		BIT(___GFP_MEMALLOC_BIT)
> +#define ___GFP_COMP		BIT(___GFP_COMP_BIT)
> +#define ___GFP_NOMEMALLOC	BIT(___GFP_NOMEMALLOC_BIT)
> +#define ___GFP_HARDWALL		BIT(___GFP_HARDWALL_BIT)
> +#define ___GFP_THISNODE		BIT(___GFP_THISNODE_BIT)
> +#define ___GFP_ACCOUNT		BIT(___GFP_ACCOUNT_BIT)
> +#define ___GFP_ZEROTAGS		BIT(___GFP_ZEROTAGS_BIT)
>  #ifdef CONFIG_KASAN_HW_TAGS
> -#define ___GFP_SKIP_ZERO	0x1000000u
> -#define ___GFP_SKIP_KASAN	0x2000000u
> +#define ___GFP_SKIP_ZERO	BIT(___GFP_SKIP_ZERO_BIT)
> +#define ___GFP_SKIP_KASAN	BIT(___GFP_SKIP_KASAN_BIT)
>  #else
>  #define ___GFP_SKIP_ZERO	0
>  #define ___GFP_SKIP_KASAN	0
>  #endif
>  #ifdef CONFIG_LOCKDEP
> -#define ___GFP_NOLOCKDEP	0x4000000u
> +#define ___GFP_NOLOCKDEP	BIT(___GFP_NOLOCKDEP_BIT)
>  #else
>  #define ___GFP_NOLOCKDEP	0
>  #endif
> -/* If the above are modified, __GFP_BITS_SHIFT may need updating */
>  
>  /*
>   * Physical address zone modifiers (see linux/mmzone.h - low four bits)
> @@ -249,7 +283,7 @@ typedef unsigned int __bitwise gfp_t;
>  #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
>  
>  /* Room for N __GFP_FOO bits */
> -#define __GFP_BITS_SHIFT (26 + IS_ENABLED(CONFIG_LOCKDEP))
> +#define __GFP_BITS_SHIFT ___GFP_LAST_BIT
>  #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
>  
>  /**
Suren Baghdasaryan Oct. 25, 2023, 3:28 p.m. UTC | #2
On Tue, Oct 24, 2023 at 10:47 PM Petr Tesařík <petr@tesarici.cz> wrote:
>
> On Tue, 24 Oct 2023 06:46:03 -0700
> Suren Baghdasaryan <surenb@google.com> wrote:
>
> > Introduce GFP bits enumeration to let compiler track the number of used
> > bits (which depends on the config options) instead of hardcoding them.
> > That simplifies __GFP_BITS_SHIFT calculation.
> > Suggested-by: Petr Tesařík <petr@tesarici.cz>
> > Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> > ---
> >  include/linux/gfp_types.h | 90 +++++++++++++++++++++++++++------------
> >  1 file changed, 62 insertions(+), 28 deletions(-)
> >
> > diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
> > index 6583a58670c5..3fbe624763d9 100644
> > --- a/include/linux/gfp_types.h
> > +++ b/include/linux/gfp_types.h
> > @@ -21,44 +21,78 @@ typedef unsigned int __bitwise gfp_t;
> >   * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
> >   */
> >
> > +enum {
> > +     ___GFP_DMA_BIT,
> > +     ___GFP_HIGHMEM_BIT,
> > +     ___GFP_DMA32_BIT,
> > +     ___GFP_MOVABLE_BIT,
> > +     ___GFP_RECLAIMABLE_BIT,
> > +     ___GFP_HIGH_BIT,
> > +     ___GFP_IO_BIT,
> > +     ___GFP_FS_BIT,
> > +     ___GFP_ZERO_BIT,
> > +     ___GFP_UNUSED_BIT,      /* 0x200u unused */
> > +     ___GFP_DIRECT_RECLAIM_BIT,
> > +     ___GFP_KSWAPD_RECLAIM_BIT,
> > +     ___GFP_WRITE_BIT,
> > +     ___GFP_NOWARN_BIT,
> > +     ___GFP_RETRY_MAYFAIL_BIT,
> > +     ___GFP_NOFAIL_BIT,
> > +     ___GFP_NORETRY_BIT,
> > +     ___GFP_MEMALLOC_BIT,
> > +     ___GFP_COMP_BIT,
> > +     ___GFP_NOMEMALLOC_BIT,
> > +     ___GFP_HARDWALL_BIT,
> > +     ___GFP_THISNODE_BIT,
> > +     ___GFP_ACCOUNT_BIT,
> > +     ___GFP_ZEROTAGS_BIT,
> > +#ifdef CONFIG_KASAN_HW_TAGS
> > +     ___GFP_SKIP_ZERO_BIT,
> > +     ___GFP_SKIP_KASAN_BIT,
> > +#endif
> > +#ifdef CONFIG_LOCKDEP
> > +     ___GFP_NOLOCKDEP_BIT,
> > +#endif
> > +     ___GFP_LAST_BIT
> > +};
> > +
> >  /* Plain integer GFP bitmasks. Do not use this directly. */
> > -#define ___GFP_DMA           0x01u
> > -#define ___GFP_HIGHMEM               0x02u
> > -#define ___GFP_DMA32         0x04u
> > -#define ___GFP_MOVABLE               0x08u
> > -#define ___GFP_RECLAIMABLE   0x10u
> > -#define ___GFP_HIGH          0x20u
> > -#define ___GFP_IO            0x40u
> > -#define ___GFP_FS            0x80u
> > -#define ___GFP_ZERO          0x100u
> > +#define ___GFP_DMA           BIT(___GFP_DMA_BIT)
> > +#define ___GFP_HIGHMEM               BIT(___GFP_HIGHMEM_BIT)
> > +#define ___GFP_DMA32         BIT(___GFP_DMA32_BIT)
> > +#define ___GFP_MOVABLE               BIT(___GFP_MOVABLE_BIT)
> > +#define ___GFP_RECLAIMABLE   BIT(___GFP_RECLAIMABLE_BIT)
> > +#define ___GFP_HIGH          BIT(___GFP_HIGH_BIT)
> > +#define ___GFP_IO            BIT(___GFP_IO_BIT)
> > +#define ___GFP_FS            BIT(___GFP_FS_BIT)
> > +#define ___GFP_ZERO          BIT(___GFP_ZERO_BIT)
> >  /* 0x200u unused */
>
> This comment can be also removed here, because it is already stated
> above with the definition of ___GFP_UNUSED_BIT.

Ack.

>
> Then again, I think that the GFP bits have never been compacted after
> Neil Brown removed __GFP_ATOMIC with commit 2973d8229b78 simply because
> that would mean changing definitions of all subsequent GFP flags. FWIW
> I am not aware of any code that would depend on the numeric value of
> ___GFP_* macros, so this patch seems like a good opportunity to change
> the numbering and get rid of this unused 0x200u altogether.
>
> @Neil: I have added you to the conversation in case you want to correct
> my understanding of the unused bit.

Hmm. I would prefer to do that in a separate patch even though it
would be a one-line change. Seems safer to me in case something goes
wrong and we have to bisect and revert it. If that sounds ok I'll post
that in the next version.

>
> Other than that LGTM.

Thanks for the review!
Suren.

>
> Petr T
>
> > -#define ___GFP_DIRECT_RECLAIM        0x400u
> > -#define ___GFP_KSWAPD_RECLAIM        0x800u
> > -#define ___GFP_WRITE         0x1000u
> > -#define ___GFP_NOWARN                0x2000u
> > -#define ___GFP_RETRY_MAYFAIL 0x4000u
> > -#define ___GFP_NOFAIL                0x8000u
> > -#define ___GFP_NORETRY               0x10000u
> > -#define ___GFP_MEMALLOC              0x20000u
> > -#define ___GFP_COMP          0x40000u
> > -#define ___GFP_NOMEMALLOC    0x80000u
> > -#define ___GFP_HARDWALL              0x100000u
> > -#define ___GFP_THISNODE              0x200000u
> > -#define ___GFP_ACCOUNT               0x400000u
> > -#define ___GFP_ZEROTAGS              0x800000u
> > +#define ___GFP_DIRECT_RECLAIM        BIT(___GFP_DIRECT_RECLAIM_BIT)
> > +#define ___GFP_KSWAPD_RECLAIM        BIT(___GFP_KSWAPD_RECLAIM_BIT)
> > +#define ___GFP_WRITE         BIT(___GFP_WRITE_BIT)
> > +#define ___GFP_NOWARN                BIT(___GFP_NOWARN_BIT)
> > +#define ___GFP_RETRY_MAYFAIL BIT(___GFP_RETRY_MAYFAIL_BIT)
> > +#define ___GFP_NOFAIL                BIT(___GFP_NOFAIL_BIT)
> > +#define ___GFP_NORETRY               BIT(___GFP_NORETRY_BIT)
> > +#define ___GFP_MEMALLOC              BIT(___GFP_MEMALLOC_BIT)
> > +#define ___GFP_COMP          BIT(___GFP_COMP_BIT)
> > +#define ___GFP_NOMEMALLOC    BIT(___GFP_NOMEMALLOC_BIT)
> > +#define ___GFP_HARDWALL              BIT(___GFP_HARDWALL_BIT)
> > +#define ___GFP_THISNODE              BIT(___GFP_THISNODE_BIT)
> > +#define ___GFP_ACCOUNT               BIT(___GFP_ACCOUNT_BIT)
> > +#define ___GFP_ZEROTAGS              BIT(___GFP_ZEROTAGS_BIT)
> >  #ifdef CONFIG_KASAN_HW_TAGS
> > -#define ___GFP_SKIP_ZERO     0x1000000u
> > -#define ___GFP_SKIP_KASAN    0x2000000u
> > +#define ___GFP_SKIP_ZERO     BIT(___GFP_SKIP_ZERO_BIT)
> > +#define ___GFP_SKIP_KASAN    BIT(___GFP_SKIP_KASAN_BIT)
> >  #else
> >  #define ___GFP_SKIP_ZERO     0
> >  #define ___GFP_SKIP_KASAN    0
> >  #endif
> >  #ifdef CONFIG_LOCKDEP
> > -#define ___GFP_NOLOCKDEP     0x4000000u
> > +#define ___GFP_NOLOCKDEP     BIT(___GFP_NOLOCKDEP_BIT)
> >  #else
> >  #define ___GFP_NOLOCKDEP     0
> >  #endif
> > -/* If the above are modified, __GFP_BITS_SHIFT may need updating */
> >
> >  /*
> >   * Physical address zone modifiers (see linux/mmzone.h - low four bits)
> > @@ -249,7 +283,7 @@ typedef unsigned int __bitwise gfp_t;
> >  #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
> >
> >  /* Room for N __GFP_FOO bits */
> > -#define __GFP_BITS_SHIFT (26 + IS_ENABLED(CONFIG_LOCKDEP))
> > +#define __GFP_BITS_SHIFT ___GFP_LAST_BIT
> >  #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
> >
> >  /**
>
>
Petr Tesařík Oct. 28, 2023, 5:21 p.m. UTC | #3
On Wed, 25 Oct 2023 08:28:32 -0700
Suren Baghdasaryan <surenb@google.com> wrote:

> On Tue, Oct 24, 2023 at 10:47 PM Petr Tesařík <petr@tesarici.cz> wrote:
> >
> > On Tue, 24 Oct 2023 06:46:03 -0700
> > Suren Baghdasaryan <surenb@google.com> wrote:
> >  
> > > Introduce GFP bits enumeration to let compiler track the number of used
> > > bits (which depends on the config options) instead of hardcoding them.
> > > That simplifies __GFP_BITS_SHIFT calculation.
> > > Suggested-by: Petr Tesařík <petr@tesarici.cz>
> > > Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> > > ---
> > >  include/linux/gfp_types.h | 90 +++++++++++++++++++++++++++------------
> > >  1 file changed, 62 insertions(+), 28 deletions(-)
> > >
> > > diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
> > > index 6583a58670c5..3fbe624763d9 100644
> > > --- a/include/linux/gfp_types.h
> > > +++ b/include/linux/gfp_types.h
> > > @@ -21,44 +21,78 @@ typedef unsigned int __bitwise gfp_t;
> > >   * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
> > >   */
> > >
> > > +enum {
> > > +     ___GFP_DMA_BIT,
> > > +     ___GFP_HIGHMEM_BIT,
> > > +     ___GFP_DMA32_BIT,
> > > +     ___GFP_MOVABLE_BIT,
> > > +     ___GFP_RECLAIMABLE_BIT,
> > > +     ___GFP_HIGH_BIT,
> > > +     ___GFP_IO_BIT,
> > > +     ___GFP_FS_BIT,
> > > +     ___GFP_ZERO_BIT,
> > > +     ___GFP_UNUSED_BIT,      /* 0x200u unused */
> > > +     ___GFP_DIRECT_RECLAIM_BIT,
> > > +     ___GFP_KSWAPD_RECLAIM_BIT,
> > > +     ___GFP_WRITE_BIT,
> > > +     ___GFP_NOWARN_BIT,
> > > +     ___GFP_RETRY_MAYFAIL_BIT,
> > > +     ___GFP_NOFAIL_BIT,
> > > +     ___GFP_NORETRY_BIT,
> > > +     ___GFP_MEMALLOC_BIT,
> > > +     ___GFP_COMP_BIT,
> > > +     ___GFP_NOMEMALLOC_BIT,
> > > +     ___GFP_HARDWALL_BIT,
> > > +     ___GFP_THISNODE_BIT,
> > > +     ___GFP_ACCOUNT_BIT,
> > > +     ___GFP_ZEROTAGS_BIT,
> > > +#ifdef CONFIG_KASAN_HW_TAGS
> > > +     ___GFP_SKIP_ZERO_BIT,
> > > +     ___GFP_SKIP_KASAN_BIT,
> > > +#endif
> > > +#ifdef CONFIG_LOCKDEP
> > > +     ___GFP_NOLOCKDEP_BIT,
> > > +#endif
> > > +     ___GFP_LAST_BIT
> > > +};
> > > +
> > >  /* Plain integer GFP bitmasks. Do not use this directly. */
> > > -#define ___GFP_DMA           0x01u
> > > -#define ___GFP_HIGHMEM               0x02u
> > > -#define ___GFP_DMA32         0x04u
> > > -#define ___GFP_MOVABLE               0x08u
> > > -#define ___GFP_RECLAIMABLE   0x10u
> > > -#define ___GFP_HIGH          0x20u
> > > -#define ___GFP_IO            0x40u
> > > -#define ___GFP_FS            0x80u
> > > -#define ___GFP_ZERO          0x100u
> > > +#define ___GFP_DMA           BIT(___GFP_DMA_BIT)
> > > +#define ___GFP_HIGHMEM               BIT(___GFP_HIGHMEM_BIT)
> > > +#define ___GFP_DMA32         BIT(___GFP_DMA32_BIT)
> > > +#define ___GFP_MOVABLE               BIT(___GFP_MOVABLE_BIT)
> > > +#define ___GFP_RECLAIMABLE   BIT(___GFP_RECLAIMABLE_BIT)
> > > +#define ___GFP_HIGH          BIT(___GFP_HIGH_BIT)
> > > +#define ___GFP_IO            BIT(___GFP_IO_BIT)
> > > +#define ___GFP_FS            BIT(___GFP_FS_BIT)
> > > +#define ___GFP_ZERO          BIT(___GFP_ZERO_BIT)
> > >  /* 0x200u unused */  
> >
> > This comment can be also removed here, because it is already stated
> > above with the definition of ___GFP_UNUSED_BIT.  
> 
> Ack.
> 
> >
> > Then again, I think that the GFP bits have never been compacted after
> > Neil Brown removed __GFP_ATOMIC with commit 2973d8229b78 simply because
> > that would mean changing definitions of all subsequent GFP flags. FWIW
> > I am not aware of any code that would depend on the numeric value of
> > ___GFP_* macros, so this patch seems like a good opportunity to change
> > the numbering and get rid of this unused 0x200u altogether.
> >
> > @Neil: I have added you to the conversation in case you want to correct
> > my understanding of the unused bit.  
> 
> Hmm. I would prefer to do that in a separate patch even though it
> would be a one-line change. Seems safer to me in case something goes
> wrong and we have to bisect and revert it. If that sounds ok I'll post
> that in the next version.

You're right. If something does go wrong, it will be easier to fix if
the removal of the unused bit is in a commit of its own.

Petr T
diff mbox series

Patch

diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
index 6583a58670c5..3fbe624763d9 100644
--- a/include/linux/gfp_types.h
+++ b/include/linux/gfp_types.h
@@ -21,44 +21,78 @@  typedef unsigned int __bitwise gfp_t;
  * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
  */
 
+enum {
+	___GFP_DMA_BIT,
+	___GFP_HIGHMEM_BIT,
+	___GFP_DMA32_BIT,
+	___GFP_MOVABLE_BIT,
+	___GFP_RECLAIMABLE_BIT,
+	___GFP_HIGH_BIT,
+	___GFP_IO_BIT,
+	___GFP_FS_BIT,
+	___GFP_ZERO_BIT,
+	___GFP_UNUSED_BIT,	/* 0x200u unused */
+	___GFP_DIRECT_RECLAIM_BIT,
+	___GFP_KSWAPD_RECLAIM_BIT,
+	___GFP_WRITE_BIT,
+	___GFP_NOWARN_BIT,
+	___GFP_RETRY_MAYFAIL_BIT,
+	___GFP_NOFAIL_BIT,
+	___GFP_NORETRY_BIT,
+	___GFP_MEMALLOC_BIT,
+	___GFP_COMP_BIT,
+	___GFP_NOMEMALLOC_BIT,
+	___GFP_HARDWALL_BIT,
+	___GFP_THISNODE_BIT,
+	___GFP_ACCOUNT_BIT,
+	___GFP_ZEROTAGS_BIT,
+#ifdef CONFIG_KASAN_HW_TAGS
+	___GFP_SKIP_ZERO_BIT,
+	___GFP_SKIP_KASAN_BIT,
+#endif
+#ifdef CONFIG_LOCKDEP
+	___GFP_NOLOCKDEP_BIT,
+#endif
+	___GFP_LAST_BIT
+};
+
 /* Plain integer GFP bitmasks. Do not use this directly. */
-#define ___GFP_DMA		0x01u
-#define ___GFP_HIGHMEM		0x02u
-#define ___GFP_DMA32		0x04u
-#define ___GFP_MOVABLE		0x08u
-#define ___GFP_RECLAIMABLE	0x10u
-#define ___GFP_HIGH		0x20u
-#define ___GFP_IO		0x40u
-#define ___GFP_FS		0x80u
-#define ___GFP_ZERO		0x100u
+#define ___GFP_DMA		BIT(___GFP_DMA_BIT)
+#define ___GFP_HIGHMEM		BIT(___GFP_HIGHMEM_BIT)
+#define ___GFP_DMA32		BIT(___GFP_DMA32_BIT)
+#define ___GFP_MOVABLE		BIT(___GFP_MOVABLE_BIT)
+#define ___GFP_RECLAIMABLE	BIT(___GFP_RECLAIMABLE_BIT)
+#define ___GFP_HIGH		BIT(___GFP_HIGH_BIT)
+#define ___GFP_IO		BIT(___GFP_IO_BIT)
+#define ___GFP_FS		BIT(___GFP_FS_BIT)
+#define ___GFP_ZERO		BIT(___GFP_ZERO_BIT)
 /* 0x200u unused */
-#define ___GFP_DIRECT_RECLAIM	0x400u
-#define ___GFP_KSWAPD_RECLAIM	0x800u
-#define ___GFP_WRITE		0x1000u
-#define ___GFP_NOWARN		0x2000u
-#define ___GFP_RETRY_MAYFAIL	0x4000u
-#define ___GFP_NOFAIL		0x8000u
-#define ___GFP_NORETRY		0x10000u
-#define ___GFP_MEMALLOC		0x20000u
-#define ___GFP_COMP		0x40000u
-#define ___GFP_NOMEMALLOC	0x80000u
-#define ___GFP_HARDWALL		0x100000u
-#define ___GFP_THISNODE		0x200000u
-#define ___GFP_ACCOUNT		0x400000u
-#define ___GFP_ZEROTAGS		0x800000u
+#define ___GFP_DIRECT_RECLAIM	BIT(___GFP_DIRECT_RECLAIM_BIT)
+#define ___GFP_KSWAPD_RECLAIM	BIT(___GFP_KSWAPD_RECLAIM_BIT)
+#define ___GFP_WRITE		BIT(___GFP_WRITE_BIT)
+#define ___GFP_NOWARN		BIT(___GFP_NOWARN_BIT)
+#define ___GFP_RETRY_MAYFAIL	BIT(___GFP_RETRY_MAYFAIL_BIT)
+#define ___GFP_NOFAIL		BIT(___GFP_NOFAIL_BIT)
+#define ___GFP_NORETRY		BIT(___GFP_NORETRY_BIT)
+#define ___GFP_MEMALLOC		BIT(___GFP_MEMALLOC_BIT)
+#define ___GFP_COMP		BIT(___GFP_COMP_BIT)
+#define ___GFP_NOMEMALLOC	BIT(___GFP_NOMEMALLOC_BIT)
+#define ___GFP_HARDWALL		BIT(___GFP_HARDWALL_BIT)
+#define ___GFP_THISNODE		BIT(___GFP_THISNODE_BIT)
+#define ___GFP_ACCOUNT		BIT(___GFP_ACCOUNT_BIT)
+#define ___GFP_ZEROTAGS		BIT(___GFP_ZEROTAGS_BIT)
 #ifdef CONFIG_KASAN_HW_TAGS
-#define ___GFP_SKIP_ZERO	0x1000000u
-#define ___GFP_SKIP_KASAN	0x2000000u
+#define ___GFP_SKIP_ZERO	BIT(___GFP_SKIP_ZERO_BIT)
+#define ___GFP_SKIP_KASAN	BIT(___GFP_SKIP_KASAN_BIT)
 #else
 #define ___GFP_SKIP_ZERO	0
 #define ___GFP_SKIP_KASAN	0
 #endif
 #ifdef CONFIG_LOCKDEP
-#define ___GFP_NOLOCKDEP	0x4000000u
+#define ___GFP_NOLOCKDEP	BIT(___GFP_NOLOCKDEP_BIT)
 #else
 #define ___GFP_NOLOCKDEP	0
 #endif
-/* If the above are modified, __GFP_BITS_SHIFT may need updating */
 
 /*
  * Physical address zone modifiers (see linux/mmzone.h - low four bits)
@@ -249,7 +283,7 @@  typedef unsigned int __bitwise gfp_t;
 #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
 
 /* Room for N __GFP_FOO bits */
-#define __GFP_BITS_SHIFT (26 + IS_ENABLED(CONFIG_LOCKDEP))
+#define __GFP_BITS_SHIFT ___GFP_LAST_BIT
 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
 
 /**