| Message ID | 1582694833-9407-3-git-send-email-mkshah@codeaurora.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Invoke rpmh_flush for non OSI targets | expand |
Quoting Maulik Shah (2020-02-25 21:27:12) > Currently rpmh ctrlr dirty flag is set for all cases regardless > of data is really changed or not. Add changes to update it when > data is updated to newer values. > > Also move dirty flag updates to happen from within cache_lock. > > Signed-off-by: Maulik Shah <mkshah@codeaurora.org> > Reviewed-by: Srinivas Rao L <lsrao@codeaurora.org> Probably worth adding a Fixes tag here? Doesn't make sense to mark something dirty when it isn't changed. > --- > drivers/soc/qcom/rpmh.c | 21 ++++++++++++++++----- > 1 file changed, 16 insertions(+), 5 deletions(-) > > diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c > index eb0ded0..83ba4e0 100644 > --- a/drivers/soc/qcom/rpmh.c > +++ b/drivers/soc/qcom/rpmh.c > @@ -139,20 +139,27 @@ static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr, > existing: > switch (state) { > case RPMH_ACTIVE_ONLY_STATE: > - if (req->sleep_val != UINT_MAX) > + if (req->sleep_val != UINT_MAX) { > req->wake_val = cmd->data; > + ctrlr->dirty = true; > + } > break; > case RPMH_WAKE_ONLY_STATE: > - req->wake_val = cmd->data; > + if (req->wake_val != cmd->data) { > + req->wake_val = cmd->data; > + ctrlr->dirty = true; > + } > break; > case RPMH_SLEEP_STATE: > - req->sleep_val = cmd->data; > + if (req->sleep_val != cmd->data) { > + req->sleep_val = cmd->data; > + ctrlr->dirty = true; > + } > break; > default: > break; Please remove the default case. There are only three states in the enum. The compiler will warn if a switch statement doesn't cover all cases and we'll know to add something here if another enum value is added in the future. > } > > - ctrlr->dirty = true; > unlock: > spin_unlock_irqrestore(&ctrlr->cache_lock, flags); > > @@ -323,6 +331,7 @@ static void invalidate_batch(struct rpmh_ctrlr *ctrlr) > list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list) > kfree(req); > INIT_LIST_HEAD(&ctrlr->batch_cache); > + ctrlr->dirty = true; > spin_unlock_irqrestore(&ctrlr->cache_lock, flags); > } > > @@ -456,6 +465,7 @@ static int send_single(struct rpmh_ctrlr *ctrlr, enum rpmh_state state, > int rpmh_flush(struct rpmh_ctrlr *ctrlr) > { > struct cache_req *p; > + unsigned long flags; > int ret; > > if (!ctrlr->dirty) { > @@ -488,7 +498,9 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr) > return ret; > } > > + spin_lock_irqsave(&ctrlr->cache_lock, flags); > ctrlr->dirty = false; > + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); So we take the spinlock to update it here. But we don't hold the spinlock to test for !dirty up above. Seems like either rpmh_flush() can only be called sequentially, or the lock added here needs to be held during the whole flush. Which way is it?
On 2/27/2020 4:13 AM, Stephen Boyd wrote: > Quoting Maulik Shah (2020-02-25 21:27:12) >> Currently rpmh ctrlr dirty flag is set for all cases regardless >> of data is really changed or not. Add changes to update it when >> data is updated to newer values. >> >> Also move dirty flag updates to happen from within cache_lock. >> >> Signed-off-by: Maulik Shah <mkshah@codeaurora.org> >> Reviewed-by: Srinivas Rao L <lsrao@codeaurora.org> > Probably worth adding a Fixes tag here? Doesn't make sense to mark > something dirty when it isn't changed. Done. will update in v8. >> --- >> drivers/soc/qcom/rpmh.c | 21 ++++++++++++++++----- >> 1 file changed, 16 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c >> index eb0ded0..83ba4e0 100644 >> --- a/drivers/soc/qcom/rpmh.c >> +++ b/drivers/soc/qcom/rpmh.c >> @@ -139,20 +139,27 @@ static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr, >> existing: >> switch (state) { >> case RPMH_ACTIVE_ONLY_STATE: >> - if (req->sleep_val != UINT_MAX) >> + if (req->sleep_val != UINT_MAX) { >> req->wake_val = cmd->data; >> + ctrlr->dirty = true; >> + } >> break; >> case RPMH_WAKE_ONLY_STATE: >> - req->wake_val = cmd->data; >> + if (req->wake_val != cmd->data) { >> + req->wake_val = cmd->data; >> + ctrlr->dirty = true; >> + } >> break; >> case RPMH_SLEEP_STATE: >> - req->sleep_val = cmd->data; >> + if (req->sleep_val != cmd->data) { >> + req->sleep_val = cmd->data; >> + ctrlr->dirty = true; >> + } >> break; >> default: >> break; > Please remove the default case. There are only three states in the enum. The > compiler will warn if a switch statement doesn't cover all cases and > we'll know to add something here if another enum value is added in the > future. Done. >> } >> >> - ctrlr->dirty = true; >> unlock: >> spin_unlock_irqrestore(&ctrlr->cache_lock, flags); >> >> @@ -323,6 +331,7 @@ static void invalidate_batch(struct rpmh_ctrlr *ctrlr) >> list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list) >> kfree(req); >> INIT_LIST_HEAD(&ctrlr->batch_cache); >> + ctrlr->dirty = true; >> spin_unlock_irqrestore(&ctrlr->cache_lock, flags); >> } >> >> @@ -456,6 +465,7 @@ static int send_single(struct rpmh_ctrlr *ctrlr, enum rpmh_state state, >> int rpmh_flush(struct rpmh_ctrlr *ctrlr) >> { >> struct cache_req *p; >> + unsigned long flags; >> int ret; >> >> if (!ctrlr->dirty) { >> @@ -488,7 +498,9 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr) >> return ret; >> } >> >> + spin_lock_irqsave(&ctrlr->cache_lock, flags); >> ctrlr->dirty = false; >> + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); > So we take the spinlock to update it here. But we don't hold the > spinlock to test for !dirty up above. Seems like either rpmh_flush() can > only be called sequentially, or the lock added here needs to be held > during the whole flush. Which way is it? Thanks, i will remove !ctrlr->dirty check within rpmh_flush() as currently we invoke it only when caches are dirty. Last cpu going down can first check dirty flag outside rpmh_flush() and decide to invoke it accoringly.
diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index eb0ded0..83ba4e0 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c @@ -139,20 +139,27 @@ static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr, existing: switch (state) { case RPMH_ACTIVE_ONLY_STATE: - if (req->sleep_val != UINT_MAX) + if (req->sleep_val != UINT_MAX) { req->wake_val = cmd->data; + ctrlr->dirty = true; + } break; case RPMH_WAKE_ONLY_STATE: - req->wake_val = cmd->data; + if (req->wake_val != cmd->data) { + req->wake_val = cmd->data; + ctrlr->dirty = true; + } break; case RPMH_SLEEP_STATE: - req->sleep_val = cmd->data; + if (req->sleep_val != cmd->data) { + req->sleep_val = cmd->data; + ctrlr->dirty = true; + } break; default: break; } - ctrlr->dirty = true; unlock: spin_unlock_irqrestore(&ctrlr->cache_lock, flags); @@ -287,6 +294,7 @@ static void cache_batch(struct rpmh_ctrlr *ctrlr, struct batch_cache_req *req) spin_lock_irqsave(&ctrlr->cache_lock, flags); list_add_tail(&req->list, &ctrlr->batch_cache); + ctrlr->dirty = true; spin_unlock_irqrestore(&ctrlr->cache_lock, flags); } @@ -323,6 +331,7 @@ static void invalidate_batch(struct rpmh_ctrlr *ctrlr) list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list) kfree(req); INIT_LIST_HEAD(&ctrlr->batch_cache); + ctrlr->dirty = true; spin_unlock_irqrestore(&ctrlr->cache_lock, flags); } @@ -456,6 +465,7 @@ static int send_single(struct rpmh_ctrlr *ctrlr, enum rpmh_state state, int rpmh_flush(struct rpmh_ctrlr *ctrlr) { struct cache_req *p; + unsigned long flags; int ret; if (!ctrlr->dirty) { @@ -488,7 +498,9 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr) return ret; } + spin_lock_irqsave(&ctrlr->cache_lock, flags); ctrlr->dirty = false; + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); return 0; } @@ -507,7 +519,6 @@ int rpmh_invalidate(const struct device *dev) int ret; invalidate_batch(ctrlr); - ctrlr->dirty = true; do { ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));