Searched hist:"7 bb7a83f" (Results 1 – 1 of 1) sorted by relevance
| /openbmc/linux/drivers/soc/qcom/ |
| H A D | rpmh-rsc.c | 7bb7a83f Mon Oct 05 00:59:55 CDT 2020 Maulik Shah <mkshah@codeaurora.org> Revert "drivers: qcom: rpmh-rsc: Use rcuidle tracepoints for rpmh"
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>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1601877596-32676-2-git-send-email-mkshah@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
|