Re: 2.6.18-rc1-mm2

[Dave Jones <davej@redhat.com>]

On Fri, Jul 14, 2006 at 10:40:01PM -0700, David Miller wrote:
 > From: Herbert Xu <herbert@gondor.apana.org.au>
 > Date: Sat, 15 Jul 2006 11:06:45 +1000
 > 
 > > -	__ret;						\
 > > +	unlikely(__ret);				\
 > 
 > Wouldn't it be cleaner to wrap this unlikely around
 > the top-level "({ })"?  When it sits on a line by
 > itself it looks strange, that much is true :)
 > 
 > Actually, the last time I saw a construct like this
 > it was a bug, someone was doing:
 > 
 > 	return unlikely(someval);
 > 
 > which turned someval into a boolean, even though what
 > was intended was that the full value was returned.

Ick, nasty.  Seems there's quite a few instances of that construct around.

arch/frv/kernel/gdb-stub.c:     return likely(!brr);
arch/frv/kernel/gdb-stub.c:     return likely(!brr);
arch/frv/kernel/gdb-stub.c:     return likely(!brr);
arch/frv/kernel/gdb-stub.c:     return likely(!brr);
arch/frv/kernel/gdb-stub.c:     return likely(!brr);
arch/frv/kernel/gdb-stub.c:     return likely(!brr);
net/sched/em_cmp.c:     return unlikely(cmp->flags & TCF_EM_CMP_TRANS);
net/dccp/options.c:     return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
fs/hugetlbfs/inode.c:   return likely(capable(CAP_IPC_LOCK) ||
fs/hugetlbfs/inode.c:   return likely(capable(CAP_IPC_LOCK) ||
include/linux/seccomp.h:        return unlikely(test_ti_thread_flag(ti, TIF_SECCOMP));
include/linux/ipv6.h:   return likely(sk->sk_state != TCP_TIME_WAIT) ?
include/linux/ipv6.h:   return likely(sk->sk_state != TCP_TIME_WAIT) ?
include/linux/tracehook.h:      return unlikely(p->utrace != NULL);
include/linux/tracehook.h:      return unlikely(tsk->utrace_flags & UTRACE_ACTION_QUIESCE);
include/linux/swapops.h:        return unlikely(swp_type(entry) == SWP_MIGRATION_READ ||
include/linux/swapops.h:        return unlikely(swp_type(entry) == SWP_MIGRATION_WRITE);
include/linux/mm.h:     return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
include/linux/mm.h:     return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
include/linux/sched.h:  return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
include/linux/sched.h:  return unlikely(test_thread_flag(TIF_NEED_RESCHED));
include/linux/skbuff.h: return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
include/linux/skbuff.h: return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
include/net/inet_timewait_sock.h:       return likely(sk->sk_state != TCP_TIME_WAIT) ?
include/net/pkt_cls.h:  return unlikely((ptr + len) < skb->tail && ptr > skb->head);
include/asm-frv/uaccess.h:      return likely(__access_ok(to, n)) ? __copy_to_user(to, from, n) : n; 

		Dave

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