diff options
| author | Steven Rostedt <srostedt@redhat.com> | 2009-09-14 09:31:35 -0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2009-09-14 09:41:57 -0400 |
| commit | 08a408161749d2406f94f4e3d47cfdbc826ad1cc (patch) | |
| tree | 6132140fe47c4825159dda8f8f438ac8baae6055 | |
| parent | 60ba77022712c7cda0eda286154bae160446b24a (diff) | |
ring-buffer: typecast cmpxchg to fix PowerPC warning
The cmpxchg used by PowerPC does the following:
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
(__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
(unsigned long)_n_, sizeof(*(ptr))); \
})
This does a type check of *ptr to both o and n.
Unfortunately, the code in ring-buffer.c assigns longs to pointers
and pointers to longs and causes a warning on PowerPC:
ring_buffer.c: In function 'rb_head_page_set':
ring_buffer.c:704: warning: initialization makes pointer from integer without a cast
ring_buffer.c:704: warning: initialization makes pointer from integer without a cast
ring_buffer.c: In function 'rb_head_page_replace':
ring_buffer.c:797: warning: initialization makes integer from pointer without a cast
This patch adds the typecasts inside cmpxchg to annotate that a long is
being cast to a pointer and a pointer is being casted to a long and this
removes the PowerPC warnings.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/ring_buffer.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 8786c350b4ca..6eef38923b07 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -701,8 +701,8 @@ static int rb_head_page_set(struct ring_buffer_per_cpu *cpu_buffer, val &= ~RB_FLAG_MASK; - ret = (unsigned long)cmpxchg(&list->next, - val | old_flag, val | new_flag); + ret = cmpxchg((unsigned long *)&list->next, + val | old_flag, val | new_flag); /* check if the reader took the page */ if ((ret & ~RB_FLAG_MASK) != val) @@ -794,7 +794,7 @@ static int rb_head_page_replace(struct buffer_page *old, val = *ptr & ~RB_FLAG_MASK; val |= RB_PAGE_HEAD; - ret = cmpxchg(ptr, val, &new->list); + ret = cmpxchg(ptr, val, (unsigned long)&new->list); return ret == val; } |