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| author | Oliver Hartkopp <socketcan@hartkopp.net> | 2011-09-23 08:23:47 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-09-29 00:32:09 -0400 |
| commit | aabdcb0b553b9c9547b1a506b34d55a764745870 (patch) | |
| tree | 4902665fccb2e69ecf1591302531a802b687a430 /net | |
| parent | d3c52173be57ec920deda28923d80b68e5630594 (diff) | |
| download | lwn-aabdcb0b553b9c9547b1a506b34d55a764745870.tar.gz lwn-aabdcb0b553b9c9547b1a506b34d55a764745870.zip | |
can bcm: fix tx_setup off-by-one errors
This patch fixes two off-by-one errors that canceled each other out.
Checking for the same condition two times in bcm_tx_timeout_tsklet() reduced
the count of frames to be sent by one. This did not show up the first time
tx_setup is invoked as an additional frame is sent due to TX_ANNONCE.
Invoking a second tx_setup on the same item led to a reduced (by 1) number of
sent frames.
Reported-by: Andre Naujoks <nautsch@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/can/bcm.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c index d6c8ae5b2e6a..c9cdb8d78e70 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -365,9 +365,6 @@ static void bcm_tx_timeout_tsklet(unsigned long data) bcm_send_to_user(op, &msg_head, NULL, 0); } - } - - if (op->kt_ival1.tv64 && (op->count > 0)) { /* send (next) frame */ bcm_can_tx(op); @@ -970,8 +967,9 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, /* spec: send can_frame when starting timer */ op->flags |= TX_ANNOUNCE; - if (op->kt_ival1.tv64 && (op->count > 0)) { - /* op->count-- is done in bcm_tx_timeout_handler */ + /* only start timer when having more frames than sent below */ + if (op->kt_ival1.tv64 && (op->count > 1)) { + /* op->count-- is done in bcm_tx_timeout_tsklet */ hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL); } else @@ -979,8 +977,11 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, HRTIMER_MODE_REL); } - if (op->flags & TX_ANNOUNCE) + if (op->flags & TX_ANNOUNCE) { bcm_can_tx(op); + if (op->kt_ival1.tv64 && (op->count > 0)) + op->count--; + } return msg_head->nframes * CFSIZ + MHSIZ; } |