diff mbox series

[v4,06/36] mm: enumerate all gfp flags

Message ID 20240221194052.927623-7-surenb@google.com (mailing list archive)
State New
Headers show
Series Memory allocation profiling | expand

Commit Message

Suren Baghdasaryan Feb. 21, 2024, 7:40 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>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 include/linux/gfp_types.h | 90 +++++++++++++++++++++++++++------------
 1 file changed, 62 insertions(+), 28 deletions(-)

Comments

Pasha Tatashin Feb. 21, 2024, 9:25 p.m. UTC | #1 
On Wed, Feb 21, 2024 at 2:41 PM 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>
> Reviewed-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Michal Hocko Feb. 22, 2024, 12:12 p.m. UTC | #2 
On Wed 21-02-24 11:40:19, Suren Baghdasaryan 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>
> Reviewed-by: Kees Cook <keescook@chromium.org>

I thought I have responded to this patch but obviously not the case.
I like this change. Makes sense even without the rest of the series.
Acked-by: Michal Hocko <mhocko@suse.com>

It seems that KASAN flags already __GFP_BITS_SHIFT which just proves how
fragile this existing scheme is.

> ---
>  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 1b6053da8754..868c8fb1bbc1 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))
>  
>  /**
> -- 
> 2.44.0.rc0.258.g7320e95886-goog
Petr Tesařík Feb. 22, 2024, 12:24 p.m. UTC | #3 
On Thu, 22 Feb 2024 13:12:29 +0100
Michal Hocko <mhocko@suse.com> wrote:

> On Wed 21-02-24 11:40:19, Suren Baghdasaryan 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>
> > Reviewed-by: Kees Cook <keescook@chromium.org>  
> 
> I thought I have responded to this patch but obviously not the case.
> I like this change. Makes sense even without the rest of the series.
> Acked-by: Michal Hocko <mhocko@suse.com>

Thank you, Michal. I also hope it can be merged without waiting for the
rest of the series.

Petr T
Suren Baghdasaryan Feb. 23, 2024, 7:26 p.m. UTC | #4 
On Thu, Feb 22, 2024 at 4:24 AM 'Petr Tesařík' via kernel-team
<kernel-team@android.com> wrote:
>
> On Thu, 22 Feb 2024 13:12:29 +0100
> Michal Hocko <mhocko@suse.com> wrote:
>
> > On Wed 21-02-24 11:40:19, Suren Baghdasaryan 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>
> > > Reviewed-by: Kees Cook <keescook@chromium.org>
> >
> > I thought I have responded to this patch but obviously not the case.
> > I like this change. Makes sense even without the rest of the series.
> > Acked-by: Michal Hocko <mhocko@suse.com>
>
> Thank you, Michal. I also hope it can be merged without waiting for the
> rest of the series.

Thanks Michal! I can post it separately. With the Ack I don't think it
will delay the rest of the series.
Thanks,
Suren.

>
> Petr T
>
> --
> To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com.
>
Suren Baghdasaryan Feb. 24, 2024, 1:59 a.m. UTC | #5 
On Fri, Feb 23, 2024 at 11:26 AM Suren Baghdasaryan <surenb@google.com> wrote:
>
> On Thu, Feb 22, 2024 at 4:24 AM 'Petr Tesařík' via kernel-team
> <kernel-team@android.com> wrote:
> >
> > On Thu, 22 Feb 2024 13:12:29 +0100
> > Michal Hocko <mhocko@suse.com> wrote:
> >
> > > On Wed 21-02-24 11:40:19, Suren Baghdasaryan 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>
> > > > Reviewed-by: Kees Cook <keescook@chromium.org>
> > >
> > > I thought I have responded to this patch but obviously not the case.
> > > I like this change. Makes sense even without the rest of the series.
> > > Acked-by: Michal Hocko <mhocko@suse.com>
> >
> > Thank you, Michal. I also hope it can be merged without waiting for the
> > rest of the series.
>
> Thanks Michal! I can post it separately. With the Ack I don't think it
> will delay the rest of the series.

Stand-alone version is posted as v5 here:
https://lore.kernel.org/all/20240224015800.2569851-1-surenb@google.com/

> Thanks,
> Suren.
>
> >
> > Petr T
> >
> > --
> > To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com.
> >
diff mbox series

Patch

diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
index 1b6053da8754..868c8fb1bbc1 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))
 
 /**