Hi,
On 8/19/2020 11:34 PM, Stephen Boyd wrote:
Quoting Maulik Shah (2020-08-19 03:07:49)
This change was done based on an test results of unmerged series of
adding RSC power domain and using .power_off callback of genpd to
invoke rpmh_flush().
Perhaps:
Commit efde2659b0fe ("drivers: qcom: rpmh-rsc: Use rcuidle tracepoints
for rpmh") was written to fix a bug seen in an unmerged series that
implemented a struct generic_pm_domain::power_off() callback calling
rpmh_flush(). See stack trace below.
Sure i will update in v2.
Call trace:
dump_backtrace+0x0/0x174
show_stack+0x20/0x2c
dump_stack+0xc8/0x124
lockdep_rcu_suspicious+0xe4/0x104
__tcs_buffer_write+0x230/0x2d0
rpmh_rsc_write_ctrl_data+0x210/0x270
rpmh_flush+0x84/0x24c
rpmh_domain_power_off+0x78/0x98
_genpd_power_off+0x40/0xc0
genpd_power_off+0x168/0x208
Later the final merged solution is to use CPU PM notification to invoke
rpmh_flush() and .power_off callback of genpd is not implemented in the
driver.
I'd also add:
CPU PM notifiers are run with RCU enabled/watching (see cpu_pm_notify()
and how it calls rcu_irq_enter_irqson() before calling the notifiers).
Sure i will update in v2.
Remove this change since RCU will not be idle during CPU PM notifications
hence not required to use _rcuidle tracepoint. Using _rcuidle tracepoint
prevented rpmh driver to be loadable module as these are not exported
symbols.
This reverts commit efde2659b0fe835732047357b2902cca14f054d9.
Cc: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>
Cc: John Stultz <john.stultz@xxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Maulik Shah <mkshah@xxxxxxxxxxxxxx>
---
Otherwise
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Thanks for the review.
Thanks,
Maulik
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
