| Message ID | 1601877596-32676-2-git-send-email-mkshah@codeaurora.org |
|---|---|
| State | Accepted |
| Commit | 7bb7a83f4d91a09ed02f6c22d10842d26528ba40 |
| Headers | show |
| Series | Modularize RPMH driver | expand |
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index a297911..35a7a50 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -497,7 +497,7 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, write_tcs_cmd(drv, RSC_DRV_CMD_MSGID, tcs_id, j, msgid); write_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j, cmd->addr); write_tcs_cmd(drv, RSC_DRV_CMD_DATA, tcs_id, j, cmd->data); - trace_rpmh_send_msg_rcuidle(drv, tcs_id, j, msgid, cmd); + trace_rpmh_send_msg(drv, tcs_id, j, msgid, cmd); } write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, cmd_complete);
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> --- drivers/soc/qcom/rpmh-rsc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)