| Message ID | 1680601458-9105-1-git-send-email-quic_vpernami@quicinc.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [V6] bus: mhi: host: Avoid ringing EV DB if there is no elements to process | expand |
On Tue, Apr 04, 2023 at 03:14:16PM +0530, Vivek Pernamitta wrote: > currently mhi_process_data_event_ring()/mhi_process_ctrl_ev_ring() > will ring DB even if there no ring elements to process. > This could cause doorbell event to be processed by MHI device > to check for any ring elements even it is none. > So ring event DB only if any event ring elements are processed. > > Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com> Slightly reworded the commit message and applied to mhi-next! - Mani > Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com> > Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > --- > changes since v6: > updating the commit text. > changes since v5: > updating the commit text. > changes since v4: > updating the commit text with more information. > changes since v3: > - Updating commit text for multiple versions of patches. > changes since v2: > - Updated comments in code. > changes since v1: > - Add an check to avoid ringing EV DB in mhi_process_ctrl_ev_ring(). > --- > drivers/bus/mhi/host/main.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c > index df0fbfe..1bbdb75 100644 > --- a/drivers/bus/mhi/host/main.c > +++ b/drivers/bus/mhi/host/main.c > @@ -961,7 +961,9 @@ int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl, > } > > read_lock_bh(&mhi_cntrl->pm_lock); > - if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) > + > + /* Ring EV DB only if there is any pending element to process */ > + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && count) > mhi_ring_er_db(mhi_event); > read_unlock_bh(&mhi_cntrl->pm_lock); > > @@ -1031,7 +1033,9 @@ int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl, > count++; > } > read_lock_bh(&mhi_cntrl->pm_lock); > - if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) > + > + /* Ring EV DB only if there is any pending element to process */ > + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && count) > mhi_ring_er_db(mhi_event); > read_unlock_bh(&mhi_cntrl->pm_lock); > > -- > 2.7.4 >
diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c index df0fbfe..1bbdb75 100644 --- a/drivers/bus/mhi/host/main.c +++ b/drivers/bus/mhi/host/main.c @@ -961,7 +961,9 @@ int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl, } read_lock_bh(&mhi_cntrl->pm_lock); - if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) + + /* Ring EV DB only if there is any pending element to process */ + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && count) mhi_ring_er_db(mhi_event); read_unlock_bh(&mhi_cntrl->pm_lock); @@ -1031,7 +1033,9 @@ int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl, count++; } read_lock_bh(&mhi_cntrl->pm_lock); - if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) + + /* Ring EV DB only if there is any pending element to process */ + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)) && count) mhi_ring_er_db(mhi_event); read_unlock_bh(&mhi_cntrl->pm_lock);