diff options
| author | Eliezer Tamir <eliezer.tamir@linux.intel.com> | 2013-06-28 15:59:26 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-07-01 14:06:47 -0700 |
| commit | ad6276e0fe724b1c8ac3a0bf138d151665ab2349 (patch) | |
| tree | 53cafc6ff855ac9d671aa6b9a77d9556054294dd | |
| parent | c9ab4d85de222f3390c67aedc9c18a50e767531e (diff) | |
| download | linux-ad6276e0fe724b1c8ac3a0bf138d151665ab2349.tar.bz2 | |
net: fix LLS debug_smp_processor_id() warning
Our use of sched_clock is OK because we don't mind the side effects
of calling it and occasionally waking up on a different CPU.
When CONFIG_DEBUG_PREEMPT is on, disable preempt before calling
sched_clock() so we don't trigger a debug_smp_processor_id() warning.
Reported-by: Cody P Schafer <devel-lists@codyps.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/ll_poll.h | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/include/net/ll_poll.h b/include/net/ll_poll.h index 5bf2b3a6129e..6d45e6f6ff4c 100644 --- a/include/net/ll_poll.h +++ b/include/net/ll_poll.h @@ -37,20 +37,40 @@ extern unsigned int sysctl_net_ll_poll __read_mostly; #define LL_FLUSH_FAILED -1 #define LL_FLUSH_BUSY -2 -/* we can use sched_clock() because we don't care much about precision +/* a wrapper to make debug_smp_processor_id() happy + * we can use sched_clock() because we don't care much about precision * we only care that the average is bounded - * we don't mind a ~2.5% imprecision so <<10 instead of *1000 + */ +#ifdef CONFIG_DEBUG_PREEMPT +static inline u64 ll_sched_clock(void) +{ + u64 rc; + + preempt_disable_notrace(); + rc = sched_clock(); + preempt_enable_no_resched_notrace(); + + return rc; +} +#else /* CONFIG_DEBUG_PREEMPT */ +static inline u64 ll_sched_clock(void) +{ + return sched_clock(); +} +#endif /* CONFIG_DEBUG_PREEMPT */ + +/* we don't mind a ~2.5% imprecision so <<10 instead of *1000 * sk->sk_ll_usec is a u_int so this can't overflow */ static inline u64 ll_sk_end_time(struct sock *sk) { - return ((u64)ACCESS_ONCE(sk->sk_ll_usec) << 10) + sched_clock(); + return ((u64)ACCESS_ONCE(sk->sk_ll_usec) << 10) + ll_sched_clock(); } /* in poll/select we use the global sysctl_net_ll_poll value */ static inline u64 ll_end_time(void) { - return ((u64)ACCESS_ONCE(sysctl_net_ll_poll) << 10) + sched_clock(); + return ((u64)ACCESS_ONCE(sysctl_net_ll_poll) << 10) + ll_sched_clock(); } static inline bool sk_valid_ll(struct sock *sk) @@ -61,7 +81,7 @@ static inline bool sk_valid_ll(struct sock *sk) static inline bool can_poll_ll(u64 end_time) { - return !time_after64(sched_clock(), end_time); + return !time_after64(ll_sched_clock(), end_time); } /* when used in sock_poll() nonblock is known at compile time to be true |