On Wednesday 13 May 2015 16:47:07 Pawel Moll wrote:
On Wed, 2015-05-13 at 16:32 +0100, Arnd Bergmann wrote:
On Wednesday 13 May 2015 16:21:24 Pawel Moll wrote:
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index df5f307..7d9879e 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -921,9 +921,8 @@ static void arm_ccn_pmu_event_start(struct perf_event *event, int flags) * attribute). */ if (!ccn->irq)
__hrtimer_start_range_ns(&ccn->dt.hrtimer,arm_ccn_pmu_timer_period(), 0,HRTIMER_MODE_REL_PINNED, 0);
hrtimer_start(&ccn->dt.hrtimer, arm_ccn_pmu_timer_period(),HRTIMER_MODE_REL_PINNED);/* Set the DT bus input, engaging the counter */ arm_ccn_pmu_xp_dt_config(event, 1);
Is this correct by itself, or do we need to pull in the branch that contains c6eb3f70d44828 ("hrtimer: Get rid of hrtimer softirq") from Thomas? The other similar patches that Thomas did contain a comment about the conversion being safe after hrtimer_start() no longer uses a softirq, but it is still in use in 4.1-rc3.
That's why I asked who should carry this patch
Now, the answer to your question is: the result will not be worse than the what was there before you pulled my updates, as the code was using normal hrtimer_start(). It's just when I realised that it should be pinned I looked at what x86 uncore pmu is doing and shamelessly (and probably a bit mindlessly) copied the "do not wakeup" version from there.
Ok, got it. I've rewritten the commit message now to reflect this, and have applied your patch on top of the next/drivers branch.
Thanks a lot for the fast roundtrip in fixing it. Hopefully, tomorrow's linux-next works better now.
Arnd
commit a78a3c8ef715b94de3ab27633866d4bde3e2226f Author: Pawel Moll pawel.moll@arm.com Date: Wed May 13 16:21:24 2015 +0100
bus: arm-ccn: Use hrtimer_start() again
hrtimer_start() will no longer defer already expired timers to the softirq in 4.2, and the __hrtimer_start_range_ns() function is getting removed, causing build errors when both the tip tree and the arm-ccn changes are merged.
This changes the code back to using hrtimer_start, which will do the right thing after this branch gets merged with the timers update from tip.
As pointed out after a discussion on the mailing list, the result will not be worse than the what was there before you pulled my updates, as the code was using normal hrtimer_start(). It's just when I realised that it should be pinned I looked at what x86 uncore pmu is doing and shamelessly (and probably a bit mindlessly) copied the "do not wakeup" version from there.
Reported-by: Mark Brown mark.brown@arm.com Signed-off-by: Pawel Moll pawel.moll@arm.com Signed-off-by: Arnd Bergmann arnd@arndb.de
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index df5f307f3244..7d9879e166cf 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -921,9 +921,8 @@ static void arm_ccn_pmu_event_start(struct perf_event *event, int flags) * attribute). */ if (!ccn->irq) - __hrtimer_start_range_ns(&ccn->dt.hrtimer, - arm_ccn_pmu_timer_period(), 0, - HRTIMER_MODE_REL_PINNED, 0); + hrtimer_start(&ccn->dt.hrtimer, arm_ccn_pmu_timer_period(), + HRTIMER_MODE_REL_PINNED);
/* Set the DT bus input, engaging the counter */ arm_ccn_pmu_xp_dt_config(event, 1);