lkml.org 
[lkml]   [2020]   [Sep]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v2 1/2] Revert "drivers: qcom: rpmh-rsc: Use rcuidle tracepoints for rpmh"
On Tue, Aug 25, 2020 at 4:22 AM Maulik Shah <mkshah@codeaurora.org> wrote:
>
> 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.
>
> 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.
>
> 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).
>
> 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@codeaurora.org>
> Cc: John Stultz <john.stultz@linaro.org>
> Cc: Stephen Rothwell <sfr@canb.auug.org.au>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Maulik Shah <mkshah@codeaurora.org>

Hey Maulik!
Thanks so much for sending out this series! I noticed this hasn't
made it to -next yet, so would it be good to resubmit it?

thanks
-john

\
 
 \ /
  Last update: 2020-09-28 22:48    [W:0.055 / U:2.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site