Re: [RESEND PATCH 2/2] lib/nodemask: inline next_node_in() and node_random()
On Fri, Aug 12, 2022 at 10:46:57AM +0530, Aneesh Kumar K.V wrote:
> Yury Norov writes:
>
> > The functions are pretty thin wrappers around find_bit engine, and
> > keeping them in c-file prevents compiler from small_const_nbits()
> > optimization, which must take place for all systems with MAX_NUMNODES
> > less than BITS_PER_LONG (default is 16 for me).
> >
> > Moving them to header file doesn't blow up the kernel size:
> > add/remove: 1/2 grow/shrink: 9/5 up/down: 968/-88 (880)
> >
> > CC: Andy Shevchenko
> > CC: Rasmus Villemoes
> > Signed-off-by: Yury Norov
> > ---
> > MAINTAINERS | 1 -
> > include/linux/nodemask.h | 27 ++-
> > lib/Makefile | 2 +-
> > lib/nodemask.c | 30 --
> > 4 files changed, 23 insertions(+), 37 deletions(-)
> > delete mode 100644 lib/nodemask.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 7c0b8f28aa25..19c8d0ef1177 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -3540,7 +3540,6 @@ F:lib/bitmap.c
> > F: lib/cpumask.c
> > F: lib/find_bit.c
> > F: lib/find_bit_benchmark.c
> > -F: lib/nodemask.c
> > F: lib/test_bitmap.c
> > F: tools/include/linux/bitmap.h
> > F: tools/include/linux/find.h
> > diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> > index 0f233b76c9ce..48ebe4007955 100644
> > --- a/include/linux/nodemask.h
> > +++ b/include/linux/nodemask.h
> > @@ -94,6 +94,7 @@
> > #include
> > #include
> > #include
> > +#include
> >
> > typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t;
> > extern nodemask_t _unused_nodemask_arg_;
> > @@ -276,7 +277,14 @@ static inline unsigned int __next_node(int n, const
> > nodemask_t *srcp)
> > * the first node in src if needed. Returns MAX_NUMNODES if src is empty.
> > */
> > #define next_node_in(n, src) __next_node_in((n), &(src))
> > -unsigned int __next_node_in(int node, const nodemask_t *srcp);
> > +static inline unsigned int __next_node_in(int node, const nodemask_t *srcp)
> > +{
> > + unsigned int ret = __next_node(node, srcp);
> > +
> > + if (ret == MAX_NUMNODES)
> > + ret = __first_node(srcp);
> > + return ret;
> > +}
> >
> > static inline void init_nodemask_of_node(nodemask_t *mask, int node)
> > {
> > @@ -493,14 +501,23 @@ static inline int num_node_state(enum node_states
> > state)
> >
> > #endif
> >
> > +/*
> > + * Return the bit number of a random bit set in the nodemask.
> > + * (returns NUMA_NO_NODE if nodemask is empty)
> > + */
> > +static inline int node_random(const nodemask_t *maskp)
> > +{
> > #if defined(CONFIG_NUMA) && (MAX_NUMNODES > 1)
> > -extern int node_random(const nodemask_t *maskp);
> > + int w, bit = NUMA_NO_NODE;
> > +
> > + w = nodes_weight(*maskp);
> > + if (w)
> > + bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
> > % w);
> > + return bit;
> > #else
> > -static inline int node_random(const nodemask_t *mask)
> > -{
> > return 0;
> > -}
> > #endif
> > +}
> >
> > #define node_online_mapnode_states[N_ONLINE]
> > #define node_possible_map node_states[N_POSSIBLE]
> > diff --git a/lib/Makefile b/lib/Makefile
> > index f99bf61f8bbc..731cea0342d1 100644
> > --- a/lib/Makefile
> > +++ b/lib/Makefile
> > @@ -33,7 +33,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
> > flex_proportions.o ratelimit.o show_mem.o \
> > is_single_threaded.o plist.o decompress.o kobject_uevent.o \
> > earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
> > -nmi_backtrace.o nodemask.o win_minmax.o memcat_p.o \
> > +nmi_backtrace.o win_minmax.o memcat_p.o \
> > buildid.o
> >
> > lib-$(CONFIG_PRINTK) += dump_stack.o
> > diff --git a/lib/nodemask.c b/lib/nodemask.c
> > deleted file mode 100644
> > index 7dad4ce8ff59..
> > --- a/lib/nodemask.c
> > +++ /dev/null
> > @@ -1,30 +0,0 @@
> > -// SPDX-License-Identifier: GPL-2.0
> > -#include
> > -#include
> > -#include
> > -
> > -unsigned int __next_node_in(int node, const nodemask_t *srcp)
> > -{
> > - unsigned int ret = __next_node(node, srcp);
> > -
> > - if (ret == MAX_NUMNODES)
> > - ret = __first_node(srcp);
> > - return ret;
> > -}
> > -EXPORT_SYMBOL(__next_node_in);
> > -
> > -#ifdef CONFIG_NUMA
> > -/*
> > - * Return the bit number of a random bit set in the nodemask.
> > - * (returns NUMA_NO_NODE if nodemask is empty)
> > - */
> > -int node_random(const nodemask_t *maskp)
> > -{
> > - int w, bit = NUMA_NO_NODE;
> > -
> > - w = nodes_weight(*maskp);
> > - if (w)
> > - bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
> > % w);
> > - return bit;
> > -}
> > -#endif
> > --
> > 2.34.1
>
> The patch that got merged (36d4b36b69590fed99356a4426c940a253a93800) still
> have lib/nodemask.c
Thanks Aneesh. I'll send a fix shortly.
Re: [RESEND PATCH 2/2] lib/nodemask: inline next_node_in() and node_random()
Yury Norov writes:
> The functions are pretty thin wrappers around find_bit engine, and
> keeping them in c-file prevents compiler from small_const_nbits()
> optimization, which must take place for all systems with MAX_NUMNODES
> less than BITS_PER_LONG (default is 16 for me).
>
> Moving them to header file doesn't blow up the kernel size:
> add/remove: 1/2 grow/shrink: 9/5 up/down: 968/-88 (880)
>
> CC: Andy Shevchenko
> CC: Rasmus Villemoes
> Signed-off-by: Yury Norov
> ---
> MAINTAINERS | 1 -
> include/linux/nodemask.h | 27 ++-
> lib/Makefile | 2 +-
> lib/nodemask.c | 30 --
> 4 files changed, 23 insertions(+), 37 deletions(-)
> delete mode 100644 lib/nodemask.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7c0b8f28aa25..19c8d0ef1177 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3540,7 +3540,6 @@ F: lib/bitmap.c
> F: lib/cpumask.c
> F: lib/find_bit.c
> F: lib/find_bit_benchmark.c
> -F: lib/nodemask.c
> F: lib/test_bitmap.c
> F: tools/include/linux/bitmap.h
> F: tools/include/linux/find.h
> diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> index 0f233b76c9ce..48ebe4007955 100644
> --- a/include/linux/nodemask.h
> +++ b/include/linux/nodemask.h
> @@ -94,6 +94,7 @@
> #include
> #include
> #include
> +#include
>
> typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t;
> extern nodemask_t _unused_nodemask_arg_;
> @@ -276,7 +277,14 @@ static inline unsigned int __next_node(int n, const
> nodemask_t *srcp)
> * the first node in src if needed. Returns MAX_NUMNODES if src is empty.
> */
> #define next_node_in(n, src) __next_node_in((n), &(src))
> -unsigned int __next_node_in(int node, const nodemask_t *srcp);
> +static inline unsigned int __next_node_in(int node, const nodemask_t *srcp)
> +{
> + unsigned int ret = __next_node(node, srcp);
> +
> + if (ret == MAX_NUMNODES)
> + ret = __first_node(srcp);
> + return ret;
> +}
>
> static inline void init_nodemask_of_node(nodemask_t *mask, int node)
> {
> @@ -493,14 +501,23 @@ static inline int num_node_state(enum node_states state)
>
> #endif
>
> +/*
> + * Return the bit number of a random bit set in the nodemask.
> + * (returns NUMA_NO_NODE if nodemask is empty)
> + */
> +static inline int node_random(const nodemask_t *maskp)
> +{
> #if defined(CONFIG_NUMA) && (MAX_NUMNODES > 1)
> -extern int node_random(const nodemask_t *maskp);
> + int w, bit = NUMA_NO_NODE;
> +
> + w = nodes_weight(*maskp);
> + if (w)
> + bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
> % w);
> + return bit;
> #else
> -static inline int node_random(const nodemask_t *mask)
> -{
> return 0;
> -}
> #endif
> +}
>
> #define node_online_map node_states[N_ONLINE]
> #define node_possible_mapnode_states[N_POSSIBLE]
> diff --git a/lib/Makefile b/lib/Makefile
> index f99bf61f8bbc..731cea0342d1 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -33,7 +33,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
>flex_proportions.o ratelimit.o show_mem.o \
>is_single_threaded.o plist.o decompress.o kobject_uevent.o \
>earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
> - nmi_backtrace.o nodemask.o win_minmax.o memcat_p.o \
> + nmi_backtrace.o win_minmax.o memcat_p.o \
>buildid.o
>
> lib-$(CONFIG_PRINTK) += dump_stack.o
> diff --git a/lib/nodemask.c b/lib/nodemask.c
> deleted file mode 100644
> index 7dad4ce8ff59..
> --- a/lib/nodemask.c
> +++ /dev/null
> @@ -1,30 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0
> -#include
> -#include
> -#include
> -
> -unsigned int __next_node_in(int node, const nodemask_t *srcp)
> -{
> - unsigned int ret = __next_node(node, srcp);
> -
> - if (ret == MAX_NUMNODES)
> - ret = __first_node(srcp);
> - return ret;
> -}
> -EXPORT_SYMBOL(__next_node_in);
> -
> -#ifdef CONFIG_NUMA
> -/*
> - * Return the bit number of a random bit set in the nodemask.
> - * (returns NUMA_NO_NODE if nodemask is empty)
> - */
> -int node_random(const nodemask_t *maskp)
> -{
> - int w, bit = NUMA_NO_NODE;
> -
> - w = nodes_weight(*maskp);
> - if (w)
> - bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
> % w);
> - return bit;
> -}
> -#endif
> --
> 2.34.1
The patch that got merged (36d4b36b69590fed99356a4426c940a253a93800) still have
lib/nodemask.c
[RESEND PATCH 2/2] lib/nodemask: inline next_node_in() and node_random()
The functions are pretty thin wrappers around find_bit engine, and
keeping them in c-file prevents compiler from small_const_nbits()
optimization, which must take place for all systems with MAX_NUMNODES
less than BITS_PER_LONG (default is 16 for me).
Moving them to header file doesn't blow up the kernel size:
add/remove: 1/2 grow/shrink: 9/5 up/down: 968/-88 (880)
CC: Andy Shevchenko
CC: Rasmus Villemoes
Signed-off-by: Yury Norov
---
MAINTAINERS | 1 -
include/linux/nodemask.h | 27 ++-
lib/Makefile | 2 +-
lib/nodemask.c | 30 --
4 files changed, 23 insertions(+), 37 deletions(-)
delete mode 100644 lib/nodemask.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7c0b8f28aa25..19c8d0ef1177 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3540,7 +3540,6 @@ F:lib/bitmap.c
F: lib/cpumask.c
F: lib/find_bit.c
F: lib/find_bit_benchmark.c
-F: lib/nodemask.c
F: lib/test_bitmap.c
F: tools/include/linux/bitmap.h
F: tools/include/linux/find.h
diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
index 0f233b76c9ce..48ebe4007955 100644
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -94,6 +94,7 @@
#include
#include
#include
+#include
typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t;
extern nodemask_t _unused_nodemask_arg_;
@@ -276,7 +277,14 @@ static inline unsigned int __next_node(int n, const
nodemask_t *srcp)
* the first node in src if needed. Returns MAX_NUMNODES if src is empty.
*/
#define next_node_in(n, src) __next_node_in((n), &(src))
-unsigned int __next_node_in(int node, const nodemask_t *srcp);
+static inline unsigned int __next_node_in(int node, const nodemask_t *srcp)
+{
+ unsigned int ret = __next_node(node, srcp);
+
+ if (ret == MAX_NUMNODES)
+ ret = __first_node(srcp);
+ return ret;
+}
static inline void init_nodemask_of_node(nodemask_t *mask, int node)
{
@@ -493,14 +501,23 @@ static inline int num_node_state(enum node_states state)
#endif
+/*
+ * Return the bit number of a random bit set in the nodemask.
+ * (returns NUMA_NO_NODE if nodemask is empty)
+ */
+static inline int node_random(const nodemask_t *maskp)
+{
#if defined(CONFIG_NUMA) && (MAX_NUMNODES > 1)
-extern int node_random(const nodemask_t *maskp);
+ int w, bit = NUMA_NO_NODE;
+
+ w = nodes_weight(*maskp);
+ if (w)
+ bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
% w);
+ return bit;
#else
-static inline int node_random(const nodemask_t *mask)
-{
return 0;
-}
#endif
+}
#define node_online_mapnode_states[N_ONLINE]
#define node_possible_map node_states[N_POSSIBLE]
diff --git a/lib/Makefile b/lib/Makefile
index f99bf61f8bbc..731cea0342d1 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -33,7 +33,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
flex_proportions.o ratelimit.o show_mem.o \
is_single_threaded.o plist.o decompress.o kobject_uevent.o \
earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
-nmi_backtrace.o nodemask.o win_minmax.o memcat_p.o \
+nmi_backtrace.o win_minmax.o memcat_p.o \
buildid.o
lib-$(CONFIG_PRINTK) += dump_stack.o
diff --git a/lib/nodemask.c b/lib/nodemask.c
deleted file mode 100644
index 7dad4ce8ff59..
--- a/lib/nodemask.c
+++ /dev/null
@@ -1,30 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include
-#include
-#include
-
-unsigned int __next_node_in(int node, const nodemask_t *srcp)
-{
- unsigned int ret = __next_node(node, srcp);
-
- if (ret == MAX_NUMNODES)
- ret = __first_node(srcp);
- return ret;
-}
-EXPORT_SYMBOL(__next_node_in);
-
-#ifdef CONFIG_NUMA
-/*
- * Return the bit number of a random bit set in the nodemask.
- * (returns NUMA_NO_NODE if nodemask is empty)
- */
-int node_random(const nodemask_t *maskp)
-{
- int w, bit = NUMA_NO_NODE;
-
- w = nodes_weight(*maskp);
- if (w)
- bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int()
% w);
- return bit;
-}
-#endif
--
2.34.1
