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| author | Maulik Shah <mkshah@codeaurora.org> | 2020-10-05 11:29:55 +0530 |
|---|---|---|
| committer | Bjorn Andersson <bjorn.andersson@linaro.org> | 2020-10-26 09:55:01 -0500 |
| commit | 7bb7a83f4d91a09ed02f6c22d10842d26528ba40 (patch) | |
| tree | bea7f537482542f88ba2f4d74f77d39b9cb83d2f /drivers/soc/qcom | |
| parent | c14e64b46944fe480d94ff33512e1855b246e690 (diff) | |
| download | linux-7bb7a83f4d91a09ed02f6c22d10842d26528ba40.tar.bz2 | |
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>
Diffstat (limited to 'drivers/soc/qcom')
| -rw-r--r-- | drivers/soc/qcom/rpmh-rsc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index a297911afe57..35a7a503f92e 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); |