Messages in this thread | | | Date | Tue, 07 Dec 2010 16:08:15 +0100 | From | Tejun Heo <> | Subject | Re: [Use cpuops V1 09/11] Connector: Use this_cpu operations |
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On 12/06/2010 06:16 PM, Christoph Lameter wrote: > get_seq can benefit from this_cpu_operations. Address calculation is avoided > and the increment is done using an xadd. > > Cc: Scott James Remnant <scott@ubuntu.com> > Cc: Mike Frysinger <vapier@gentoo.org> > Signed-off-by: Christoph Lameter <cl@linux.com> > > --- > drivers/connector/cn_proc.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > Index: linux-2.6/drivers/connector/cn_proc.c > =================================================================== > --- linux-2.6.orig/drivers/connector/cn_proc.c 2010-11-30 09:38:33.000000000 -0600 > +++ linux-2.6/drivers/connector/cn_proc.c 2010-11-30 09:39:38.000000000 -0600 > @@ -43,9 +43,10 @@ static DEFINE_PER_CPU(__u32, proc_event_ > > static inline void get_seq(__u32 *ts, int *cpu) > { > - *ts = get_cpu_var(proc_event_counts)++; > + preempt_disable(); > + *ts = __this_cpu_inc(proc_event_counts);
Eh? __this_cpu_inc() evaluates to the incremented value?
-- tejun
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