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net_sched: move TCQ_F_THROTTLED flag

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In commit 3711210576 (net: QDISC_STATE_RUNNING dont need atomic bit
ops) I moved QDISC_STATE_RUNNING flag to __state container, located in
the cache line containing qdisc lock and often dirtied fields.

I now move TCQ_F_THROTTLED bit too, so that we let first cache line read
mostly, and shared by all cpus. This should speedup HTB/CBQ for example.

Not using test_bit()/__clear_bit()/__test_and_set_bit allows to use an
"unsigned int" for __state container, reducing by 8 bytes Qdisc size.

Introduce helpers to hide implementation details.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
CC: Jesper Dangaard Brouer <hawk@diku.dk>
CC: Jarek Poplawski <jarkao2@gmail.com>
CC: Jamal Hadi Salim <hadi@cyberus.ca>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2011-01-20 05:27:16 +00:00
committed by David S. Miller
parent 817fb15dfd
commit fd245a4adb
7 changed files with 39 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
include/net/sch_generic.h
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@@ -31,7 +31,8 @@ enum qdisc_state_t {
* following bits are only changed while qdisc lock is held
*/
enum qdisc___state_t {
__QDISC___STATE_RUNNING,
__QDISC___STATE_RUNNING = 1,
__QDISC___STATE_THROTTLED = 2,
};
struct qdisc_size_table {
@@ -46,10 +47,9 @@ struct Qdisc {
struct sk_buff * (*dequeue)(struct Qdisc *dev);
unsigned flags;
#define TCQ_F_BUILTIN 1
#define TCQ_F_THROTTLED 2
#define TCQ_F_INGRESS 4
#define TCQ_F_CAN_BYPASS 8
#define TCQ_F_MQROOT 16
#define TCQ_F_INGRESS 2
#define TCQ_F_CAN_BYPASS 4
#define TCQ_F_MQROOT 8
#define TCQ_F_WARN_NONWC (1 << 16)
int padded;
struct Qdisc_ops *ops;
@@ -78,25 +78,43 @@ struct Qdisc {
unsigned long state;
struct sk_buff_head q;
struct gnet_stats_basic_packed bstats;
unsigned long __state;
unsigned int __state;
struct gnet_stats_queue qstats;
struct rcu_head rcu_head;
spinlock_t busylock;
};
static inline bool qdisc_is_running(struct Qdisc *qdisc)
static inline bool qdisc_is_running(const struct Qdisc *qdisc)
{
return test_bit(__QDISC___STATE_RUNNING, &qdisc->__state);
return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
}
static inline bool qdisc_run_begin(struct Qdisc *qdisc)
{
return !__test_and_set_bit(__QDISC___STATE_RUNNING, &qdisc->__state);
if (qdisc_is_running(qdisc))
return false;
qdisc->__state |= __QDISC___STATE_RUNNING;
return true;
}
static inline void qdisc_run_end(struct Qdisc *qdisc)
{
__clear_bit(__QDISC___STATE_RUNNING, &qdisc->__state);
qdisc->__state &= ~__QDISC___STATE_RUNNING;
}
static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
{
return (qdisc->__state & __QDISC___STATE_THROTTLED) ? true : false;
}
static inline void qdisc_throttled(struct Qdisc *qdisc)
{
qdisc->__state |= __QDISC___STATE_THROTTLED;
}
static inline void qdisc_unthrottled(struct Qdisc *qdisc)
{
qdisc->__state &= ~__QDISC___STATE_THROTTLED;
}
struct Qdisc_class_ops {