On 1 April 2014 12:03, Viresh Kumar viresh.kumar@linaro.org wrote:
So here is the patch by patch analysis (With x86_64_defconfig):
Initial details: text data bss dec hex filename 7989 408 0 8397 20cd ../bx86/kernel/hrtimer.o
73a6cd8 hrtimer: replace 'tab' with 'space' after comma ',' 04223a8 hrtimer: Coalesce format fragments in printk() 52fac3f hrtimer: call hrtimer_set_expires_range() from hrtimer_set_expires_range_ns() 535a552 hrtimer: use base->index instead of basenum in switch_hrtimer_base()
7989 408 0 8397 20cd ../bx86/kernel/hrtimer.o
f3a2cdd hrtimer: no need to rewrite '1' to hrtimer_hres_enabled
7974 408 0 8382 20be ../bx86/kernel/hrtimer.o
This one actually made a smaller :)
479d66f hrtimer: don't rewrite same value to expires_next in hrtimer_force_reprogram()
7990 408 0 8398 20ce ../bx86/kernel/hrtimer.o
0e134df hrtimer: use base->hres_active directly instead of hrtimer_hres_active()
8006 408 0 8414 20de ../bx86/kernel/hrtimer.o
So, reading from a per-cpu variable is efficient as compared to base->hres_active. In that case this patch can be dropped :)
Its a bit awkward now. When I keep this patch at this location it exactly generates above numbers, i.e. 7990 -> 8006.
But if I revert this patch over top of all 30 commits I have, it doesn't make a difference. Even applying it again over the revert doesn't make a difference.
There are no other changes to the concerned routine, retrigger_next_event() in my commits..