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dpaa2-eth: Remove preempt_disable() from seed_pool() 

According to the comment, the preempt_disable() statement is required
due to synchronisation in napi_alloc_frag(). The awful truth is that
local_bh_disable() is required because otherwise the NAPI poll callback
can be invoked while the open function setup buffers. This isn't
unlikely since the dpaa2 provides multiple devices.

The usage of napi_alloc_frag() has been removed in commit

 27c874867c ("dpaa2-eth: Use a single page per Rx buffer")

which means that the comment is not accurate and the preempt_disable()
statement is not required.

Remove the outdated comment and the no longer required
preempt_disable().

Cc: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Acked-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sebastian Andrzej Siewior 2019-06-07 21:20:36 +02:00 committed by David S. Miller
parent 92dcabd7a0
commit f9dae5554a
1 changed files with 0 additions and 9 deletions
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9
drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
View File

@ -997,13 +997,6 @@ static int seed_pool(struct dpaa2_eth_priv *priv, u16 bpid)
int i, j;
int new_count;
/* This is the lazy seeding of Rx buffer pools.
* dpaa2_add_bufs() is also used on the Rx hotpath and calls
* napi_alloc_frag(). The trouble with that is that it in turn ends up
* calling this_cpu_ptr(), which mandates execution in atomic context.
* Rather than splitting up the code, do a one-off preempt disable.
*/
preempt_disable();
for (j = 0; j < priv->num_channels; j++) {
for (i = 0; i < DPAA2_ETH_NUM_BUFS;
i += DPAA2_ETH_BUFS_PER_CMD) {
@ -1011,12 +1004,10 @@ static int seed_pool(struct dpaa2_eth_priv *priv, u16 bpid)
priv->channel[j]->buf_count += new_count;
if (new_count < DPAA2_ETH_BUFS_PER_CMD) {
preempt_enable();
return -ENOMEM;
}
}
}
preempt_enable();
return 0;
}