diff options
| author | Allan Stephens | 2008-03-06 15:08:10 -0800 |
|---|---|---|
| committer | David S. Miller | 2008-03-06 15:08:10 -0800 |
| commit | c0cb7ef08667374f0cbe8c94c819f74a6c935135 (patch) | |
| tree | 9f609c48c03f8cf03002f1b00e6708ee79808de4 | |
| parent | 37695420a233aa8aef40c68cb338ad09e0241ec3 (diff) | |
[TIPC]: Enhancements to message header writing
This patch makes two enhancements to the routine used to
set bit fields within a TIPC message header:
1) It now ignores any bits of the new field value that are not
covered by the mask being used. (Previously, if the new value
exceeded the size of the mask the extra bits could corrupt
other fields in the message header word being updated.)
2) The code has been optimized to minimize the number of run-time
endianness conversion operations by leveraging the fact that the
mask (and, in some cases, the value as well) is constant and the
necessary conversion can be performed by the compiler.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/tipc/msg.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/tipc/msg.h b/net/tipc/msg.h index 88a2ee03bb2a..6ad070d87702 100644 --- a/net/tipc/msg.h +++ b/net/tipc/msg.h @@ -70,8 +70,10 @@ static inline void msg_set_bits(struct tipc_msg *m, u32 w, u32 pos, u32 mask, u32 val) { val = (val & mask) << pos; - m->hdr[w] &= ~htonl(mask << pos); - m->hdr[w] |= htonl(val); + val = htonl(val); + mask = htonl(mask << pos); + m->hdr[w] &= ~mask; + m->hdr[w] |= val; } /* |