diff options
| author | Eli Billauer <eli.billauer@gmail.com> | 2014-08-16 19:57:57 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-08-31 00:14:41 +0400 |
| commit | f66a49766fdfcb8186056bd44a407594c6a3d5ff (patch) | |
| tree | 022de300eb05a08a97ab2d69cb9bb7193de40f90 /drivers/staging/xillybus | |
| parent | a5b2e028bb47b4d6f4508e41120cfb2ea8aa9cac (diff) | |
| download | linux-f66a49766fdfcb8186056bd44a407594c6a3d5ff.tar.xz | |
staging: xillybus: Removed mmiowb() before mutex_unlock()
The relevant sequences consist of two I/O memory writes. The second write
depends on the first one. mmiowb() was inserted to make sure that no other
thread inserts a "first write" before the current one finished its second.
As a mutex protects this critical sequence, mmiowb() is unnecessary.
Signed-off-by: Eli Billauer <eli.billauer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/xillybus')
| -rw-r--r-- | drivers/staging/xillybus/xillybus_core.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/drivers/staging/xillybus/xillybus_core.c b/drivers/staging/xillybus/xillybus_core.c index 93a3c61b1cd5..138c0695e290 100644 --- a/drivers/staging/xillybus/xillybus_core.c +++ b/drivers/staging/xillybus/xillybus_core.c @@ -908,8 +908,6 @@ static ssize_t xillybus_read(struct file *filp, char __user *userbuf, channel->endpoint->registers + fpga_buf_ctrl_reg); - mmiowb(); /* Just to appear safe */ - mutex_unlock(&channel->endpoint-> register_mutex); } @@ -1118,7 +1116,6 @@ static int xillybus_myflush(struct xilly_channel *channel, long timeout) (2 << 24) | /* Opcode 2, submit buffer */ (bufidx << 12), channel->endpoint->registers + fpga_buf_ctrl_reg); - mmiowb(); /* Just to appear safe */ mutex_unlock(&channel->endpoint->register_mutex); } else if (bufidx == 0) @@ -1369,7 +1366,6 @@ static ssize_t xillybus_write(struct file *filp, const char __user *userbuf, (bufidx << 12), channel->endpoint->registers + fpga_buf_ctrl_reg); - mmiowb(); /* Just to appear safe */ mutex_unlock(&channel->endpoint-> register_mutex); |