Messages in this thread Patch in this message |  | | From | Frederic Weisbecker <> | Subject | [RFC PATCH 17/30] isdn: Prepare isdn_net_get_locked_lp() for handling softirq mask | Date | Thu, 11 Oct 2018 01:12:04 +0200 |
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This function is implemented on top of spin_lock_bh() that is going to handle a softirq mask in order to apply finegrained vector disablement. The lock function is going to return the previous vectors enabled mask prior to the last call to local_bh_disable(), following a similar model to that of local_irq_save/restore. Subsequent calls to local_bh_disable() and friends can then stack up:
bh = local_bh_disable(vec_mask); isdn_net_get_locked_lp(&bh2) { spin_lock(...) *bh2 = local_bh_disable(...) } ... spin_unlock_bh(bh2, ...); local_bh_enable(bh);
To prepare for that, make isdn_net_get_locked_lp() able to return a saved vector enabled mask. We'll plug it to spin_[un]lock_bh() in a subsequent patch.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: David S. Miller <davem@davemloft.net> Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> --- drivers/isdn/i4l/isdn_concap.c | 3 ++- drivers/isdn/i4l/isdn_net.c | 3 ++- drivers/isdn/i4l/isdn_net.h | 3 ++- drivers/isdn/i4l/isdn_ppp.c | 3 ++- 4 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/isdn/i4l/isdn_concap.c b/drivers/isdn/i4l/isdn_concap.c index 336523e..4352bec 100644 --- a/drivers/isdn/i4l/isdn_concap.c +++ b/drivers/isdn/i4l/isdn_concap.c @@ -41,9 +41,10 @@ static int isdn_concap_dl_data_req(struct concap_proto *concap, struct sk_buff *skb) { + unsigned int bh; struct net_device *ndev = concap->net_dev; isdn_net_dev *nd = ((isdn_net_local *) netdev_priv(ndev))->netdev; - isdn_net_local *lp = isdn_net_get_locked_lp(nd); + isdn_net_local *lp = isdn_net_get_locked_lp(nd, &bh); IX25DEBUG("isdn_concap_dl_data_req: %s \n", concap->net_dev->name); if (!lp) { diff --git a/drivers/isdn/i4l/isdn_net.c b/drivers/isdn/i4l/isdn_net.c index c138f66..a9687ca 100644 --- a/drivers/isdn/i4l/isdn_net.c +++ b/drivers/isdn/i4l/isdn_net.c @@ -1054,6 +1054,7 @@ isdn_net_xmit(struct net_device *ndev, struct sk_buff *skb) isdn_net_local *slp; isdn_net_local *lp = netdev_priv(ndev); int retv = NETDEV_TX_OK; + unsigned int bh; if (((isdn_net_local *) netdev_priv(ndev))->master) { printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__); @@ -1068,7 +1069,7 @@ isdn_net_xmit(struct net_device *ndev, struct sk_buff *skb) } #endif nd = ((isdn_net_local *) netdev_priv(ndev))->netdev; - lp = isdn_net_get_locked_lp(nd); + lp = isdn_net_get_locked_lp(nd, &bh); if (!lp) { printk(KERN_WARNING "%s: all channels busy - requeuing!\n", ndev->name); return NETDEV_TX_BUSY; diff --git a/drivers/isdn/i4l/isdn_net.h b/drivers/isdn/i4l/isdn_net.h index cca6d68..f4621b1 100644 --- a/drivers/isdn/i4l/isdn_net.h +++ b/drivers/isdn/i4l/isdn_net.h @@ -76,7 +76,8 @@ static __inline__ int isdn_net_lp_busy(isdn_net_local *lp) * For the given net device, this will get a non-busy channel out of the * corresponding bundle. The returned channel is locked. */ -static __inline__ isdn_net_local *isdn_net_get_locked_lp(isdn_net_dev *nd) +static __inline__ isdn_net_local *isdn_net_get_locked_lp(isdn_net_dev *nd, + unsigned int *bh) { unsigned long flags; isdn_net_local *lp; diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c index a7b275e..4c5ac13 100644 --- a/drivers/isdn/i4l/isdn_ppp.c +++ b/drivers/isdn/i4l/isdn_ppp.c @@ -1258,6 +1258,7 @@ isdn_ppp_xmit(struct sk_buff *skb, struct net_device *netdev) unsigned int proto = PPP_IP; /* 0x21 */ struct ippp_struct *ipt, *ipts; int slot, retval = NETDEV_TX_OK; + unsigned int bh; mlp = netdev_priv(netdev); nd = mlp->netdev; /* get master lp */ @@ -1292,7 +1293,7 @@ isdn_ppp_xmit(struct sk_buff *skb, struct net_device *netdev) goto out; } - lp = isdn_net_get_locked_lp(nd); + lp = isdn_net_get_locked_lp(nd, &bh); if (!lp) { printk(KERN_WARNING "%s: all channels busy - requeuing!\n", netdev->name); retval = NETDEV_TX_BUSY; -- 2.7.4
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