In message <Pine.LNX.4.44.0206190907520.2053-100000@home.transmeta.com> you wri
te:
>
>
> On Thu, 20 Jun 2002, Rusty Russell wrote:
> > > and then add a few simple operations like
> > >
> > > cpumask_and(cpu_mask_t * res, cpu_mask_t *a, cpu_mask_t *b);
> >
> > Sure... or just make all archs supply a "cpus_online_of(mask)" which
> > does that, unless there are other interesting cases. Or we can go the
> > other way and have a general "and_region(void *res, void *a, void *b,
> > int len)". Which one do you want?
>
> There are definitely other "interesting" cases that already do the full
> bitwise and/or on bitmasks - see sigset_t and sigaddset/sigdelset/
> sigfillset. It's really the exact same code, and the exact same issues.
>
> The problem with a generic "and_region" is that it's a slight amount of
> work to make sure that we optimize for the common cases (and since I'm not
> a huge believer in hundreds of nodes, I consider the common case to be a
> single word). And do things like just automatically get the UP case right:
> which we do right now by just virtue of having a constant cpu_online_mask,
> and letting the compiler just do the (obvious) optimizations.
Sure, completely agreed.
Normal tricks here: 1 long turns into equivalent to dst = a & b, the
other cases are handled with varying amount of suckiness. Code and
optimization tested on 2.95.4 and 3.0.4 (both PPC), kernel compiled on
my x86 box back in .au.
> It would probably make sense to make a real <linux/bitmap.h>, move the
> bitmap_member() there (and rename to "bitmap_declare()" - it's called
> member because all the places I first looked at were structure members),
> and add some simple generic routines for handling these things.
I renamed it to DECLARE_BITMAP() to match list, mutex et al. and moved
it to linux/bitops.h.
PS. Please sort out merging with Paulus's stuff: I'd like to compile
on PPC soon since I'm laptop-only for two more weeks 8)
Rusty.
-- Anyone who quotes me in their sig is an idiot. -- Rusty Russell.diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/include/linux/bitops.h working-2.5.23-bitops/include/linux/bitops.h --- linux-2.5.23/include/linux/bitops.h Fri Jun 7 13:59:07 2002 +++ working-2.5.23-bitops/include/linux/bitops.h Thu Jun 20 06:55:51 2002 @@ -2,6 +2,27 @@ #define _LINUX_BITOPS_H #include <asm/bitops.h> +#define DECLARE_BITMAP(name,bits) \ + unsigned long name[((bits)+BITS_PER_LONG-1)/BITS_PER_LONG] + +#ifndef HAVE_ARCH_AND_REGION +void __and_region(unsigned long num, unsigned char *dst, + const unsigned char *a, const unsigned char *b); +#endif + +/* For the moment, handle 1 long case fast, leave rest to __and_region. */ +#define and_region(num,dst,a,b) \ +do { \ + if (__alignof__(*(a)) == __alignof__(long) \ + && __alignof__(*(b)) == __alignof__(long) \ + && __builtin_constant_p(num) \ + && (num) == sizeof(long)) { \ + *((unsigned long *)(dst)) = \ + (*(unsigned long *)(a) & *(unsigned long *)(b)); \ + } else \ + __and_region((num), (void*)(dst), (void*)(a), (void*)(b)); \ +} while(0) + /* * ffs: find first bit set. This is defined the same way as * the libc and compiler builtin ffs routines, therefore @@ -106,8 +127,5 @@ res = (res & 0x33) + ((res >> 2) & 0x33); return (res & 0x0F) + ((res >> 4) & 0x0F); } - -#include <asm/bitops.h> - #endif diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/include/linux/types.h working-2.5.23-bitops/include/linux/types.h --- linux-2.5.23/include/linux/types.h Mon Jun 17 23:19:25 2002 +++ working-2.5.23-bitops/include/linux/types.h Thu Jun 20 06:14:39 2002 @@ -3,9 +3,6 @@ #ifdef __KERNEL__ #include <linux/config.h> - -#define bitmap_member(name,bits) \ - unsigned long name[((bits)+BITS_PER_LONG-1)/BITS_PER_LONG] #endif #include <linux/posix_types.h> diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/include/sound/ac97_codec.h working-2.5.23-bitops/include/sound/ac97_codec.h --- linux-2.5.23/include/sound/ac97_codec.h Mon Jun 17 23:19:25 2002 +++ working-2.5.23-bitops/include/sound/ac97_codec.h Thu Jun 20 06:31:35 2002 @@ -25,6 +25,7 @@ * */ +#include <linux/bitops.h> #include "control.h" #include "info.h" @@ -160,7 +161,7 @@ unsigned int rates_mic_adc; unsigned int spdif_status; unsigned short regs[0x80]; /* register cache */ - bitmap_member(reg_accessed, 0x80); /* bit flags */ + DECLARE_BITMAP(reg_accessed, 0x80); /* bit flags */ union { /* vendor specific code */ struct { unsigned short unchained[3]; // 0 = C34, 1 = C79, 2 = C69 diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/kernel/Makefile working-2.5.23-bitops/kernel/Makefile --- linux-2.5.23/kernel/Makefile Mon Jun 10 16:03:56 2002 +++ working-2.5.23-bitops/kernel/Makefile Thu Jun 20 06:27:29 2002 @@ -10,12 +10,12 @@ O_TARGET := kernel.o export-objs = signal.o sys.o kmod.o context.o ksyms.o pm.o exec_domain.o \ - printk.o platform.o suspend.o + printk.o platform.o suspend.o bitops.o obj-y = sched.o dma.o fork.o exec_domain.o panic.o printk.o \ module.o exit.o itimer.o time.o softirq.o resource.o \ sysctl.o capability.o ptrace.o timer.o user.o \ - signal.o sys.o kmod.o context.o futex.o platform.o + signal.o sys.o kmod.o context.o futex.o platform.o bitops.o obj-$(CONFIG_UID16) += uid16.o obj-$(CONFIG_MODULES) += ksyms.o diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/kernel/bitops.c working-2.5.23-bitops/kernel/bitops.c --- linux-2.5.23/kernel/bitops.c Thu Jan 1 10:00:00 1970 +++ working-2.5.23-bitops/kernel/bitops.c Thu Jun 20 06:52:29 2002 @@ -0,0 +1,32 @@ +#include <linux/config.h> +#include <linux/bitops.h> +#include <linux/module.h> + +#ifndef HAVE_ARCH_AND_REGION +/* Generic is fairly stupid: archs should optimize properly. */ +void __and_region(unsigned long num, unsigned char *dst, + const unsigned char *a, const unsigned char *b) +{ + unsigned long i; + + /* Copy first bytes, until one is long aligned. */ + for (i = 0; i < num && ((unsigned long)a+i) % __alignof__(long); i++) + dst[i] = (a[i] & b[i]); + + /* If they are all aligned, do long-at-a-time copy */ + if (((unsigned long)b+i)%__alignof__(long) == 0 + && ((unsigned long)dst+i)%__alignof__(long) == 0) { + for (; i + sizeof(long) <= num; i += sizeof(long)) { + *(unsigned long *)(dst+i) + = (*(unsigned long *)(a+i) + & *(unsigned long *)(b+i)); + } + } + + /* Do whatever is left. */ + for (; i < num; i++) + dst[i] = (a[i] & b[i]); +} + +EXPORT_SYMBOL(__and_region); +#endif diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/sound/core/seq/seq_clientmgr.h working-2.5.23-bitops/sound/core/seq/seq_clientmgr.h --- linux-2.5.23/sound/core/seq/seq_clientmgr.h Mon Jun 17 23:19:26 2002 +++ working-2.5.23-bitops/sound/core/seq/seq_clientmgr.h Thu Jun 20 06:34:16 2002 @@ -53,8 +53,8 @@ char name[64]; /* client name */ int number; /* client number */ unsigned int filter; /* filter flags */ - bitmap_member(client_filter, 256); - bitmap_member(event_filter, 256); + DECLARE_BITMAP(client_filter, 256); + DECLARE_BITMAP(event_filter, 256); snd_use_lock_t use_lock; int event_lost; /* ports */ diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.23/sound/core/seq/seq_queue.h working-2.5.23-bitops/sound/core/seq/seq_queue.h --- linux-2.5.23/sound/core/seq/seq_queue.h Mon Jun 17 23:19:26 2002 +++ working-2.5.23-bitops/sound/core/seq/seq_queue.h Thu Jun 20 06:34:11 2002 @@ -26,6 +26,7 @@ #include "seq_lock.h" #include <linux/interrupt.h> #include <linux/list.h> +#include <linux/bitops.h> #define SEQ_QUEUE_NO_OWNER (-1) @@ -51,7 +52,7 @@ spinlock_t check_lock; /* clients which uses this queue (bitmap) */ - bitmap_member(clients_bitmap,SNDRV_SEQ_MAX_CLIENTS); + DECLARE_BITMAP(clients_bitmap,SNDRV_SEQ_MAX_CLIENTS); unsigned int clients; /* users of this queue */ struct semaphore timer_mutex; 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This archive was generated by hypermail 2b29 : Sun Jun 23 2002 - 22:00:20 EST