| Message ID | 20220811094237.77632-3-manivannan.sadhasivam@linaro.org (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Lorenzo Pieralisi |
| Headers | show |
| Series | PCI: endpoint: Rework the EPC to EPF notification | expand |
Hi Mani, On 11/08/22 15:12, Manivannan Sadhasivam wrote: > As a part of the transition towards callback mechanism for signalling the > events from EPC to EPF, let's use the link_up() callback in the place of > the LINK_UP notifier. This also removes the notifier support completely > from the PCI endpoint framework. > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > --- > drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++------------- > drivers/pci/endpoint/pci-epc-core.c | 8 +++-- > include/linux/pci-epc.h | 8 ----- > include/linux/pci-epf.h | 8 ++--- > 4 files changed, 18 insertions(+), 39 deletions(-) > . . <snip> . . > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > index 805f3d64f93b..a51ba9f158c3 100644 > --- a/drivers/pci/endpoint/pci-epc-core.c > +++ b/drivers/pci/endpoint/pci-epc-core.c > @@ -690,10 +690,15 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf); > */ > void pci_epc_linkup(struct pci_epc *epc) > { > + struct pci_epf *epf; > + > if (!epc || IS_ERR(epc)) > return; > > - atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); > + list_for_each_entry(epf, &epc->pci_epf, list) { > + if (epf->event_ops->link_up) > + epf->event_ops->link_up(epf); > + } how do you ensure there is no race while invoking the call back functions during add/remove of epf? Thanks, Kishon
On Thu, Aug 25, 2022 at 03:47:10PM +0530, Kishon Vijay Abraham I wrote: > Hi Mani, > > On 11/08/22 15:12, Manivannan Sadhasivam wrote: > > As a part of the transition towards callback mechanism for signalling the > > events from EPC to EPF, let's use the link_up() callback in the place of > > the LINK_UP notifier. This also removes the notifier support completely > > from the PCI endpoint framework. > > > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > > --- > > drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++------------- > > drivers/pci/endpoint/pci-epc-core.c | 8 +++-- > > include/linux/pci-epc.h | 8 ----- > > include/linux/pci-epf.h | 8 ++--- > > 4 files changed, 18 insertions(+), 39 deletions(-) > > > > . > . > <snip> > . > . > > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > > index 805f3d64f93b..a51ba9f158c3 100644 > > --- a/drivers/pci/endpoint/pci-epc-core.c > > +++ b/drivers/pci/endpoint/pci-epc-core.c > > @@ -690,10 +690,15 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf); > > */ > > void pci_epc_linkup(struct pci_epc *epc) > > { > > + struct pci_epf *epf; > > + > > if (!epc || IS_ERR(epc)) > > return; > > > > - atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); > > + list_for_each_entry(epf, &epc->pci_epf, list) { > > + if (epf->event_ops->link_up) > > + epf->event_ops->link_up(epf); > > + } > > how do you ensure there is no race while invoking the call back > functions during add/remove of epf? > Good catch! These should be guarded by epf->lock. Thanks, Mani > Thanks, > Kishon
On Wed, Aug 31, 2022 at 01:50:25PM +0530, Manivannan Sadhasivam wrote: > On Thu, Aug 25, 2022 at 03:47:10PM +0530, Kishon Vijay Abraham I wrote: > > Hi Mani, > > > > On 11/08/22 15:12, Manivannan Sadhasivam wrote: > > > As a part of the transition towards callback mechanism for signalling the > > > events from EPC to EPF, let's use the link_up() callback in the place of > > > the LINK_UP notifier. This also removes the notifier support completely > > > from the PCI endpoint framework. > > > > > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > > > --- > > > drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++------------- > > > drivers/pci/endpoint/pci-epc-core.c | 8 +++-- > > > include/linux/pci-epc.h | 8 ----- > > > include/linux/pci-epf.h | 8 ++--- > > > 4 files changed, 18 insertions(+), 39 deletions(-) > > > > > > > . > > . > > <snip> > > . > > . > > > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > > > index 805f3d64f93b..a51ba9f158c3 100644 > > > --- a/drivers/pci/endpoint/pci-epc-core.c > > > +++ b/drivers/pci/endpoint/pci-epc-core.c > > > @@ -690,10 +690,15 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf); > > > */ > > > void pci_epc_linkup(struct pci_epc *epc) > > > { > > > + struct pci_epf *epf; > > > + > > > if (!epc || IS_ERR(epc)) > > > return; > > > > > > - atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); > > > + list_for_each_entry(epf, &epc->pci_epf, list) { > > > + if (epf->event_ops->link_up) > > > + epf->event_ops->link_up(epf); > > > + } > > > > how do you ensure there is no race while invoking the call back > > functions during add/remove of epf? > > > > Good catch! These should be guarded by epf->lock. I shall wait for v2 then and mark this one as "Changes requested". Lorenzo
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index 069943b57029..37454538c000 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -731,30 +731,21 @@ static int pci_epf_test_core_init(struct pci_epf *epf) return 0; } -static const struct pci_epc_event_ops pci_epf_test_event_ops = { - .core_init = pci_epf_test_core_init, -}; - -static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val, - void *data) +int pci_epf_test_link_up(struct pci_epf *epf) { - struct pci_epf *epf = container_of(nb, struct pci_epf, nb); struct pci_epf_test *epf_test = epf_get_drvdata(epf); - switch (val) { - case LINK_UP: - queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler, - msecs_to_jiffies(1)); - break; - - default: - dev_err(&epf->dev, "Invalid EPF test notifier event\n"); - return NOTIFY_BAD; - } + queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler, + msecs_to_jiffies(1)); - return NOTIFY_OK; + return 0; } +static const struct pci_epc_event_ops pci_epf_test_event_ops = { + .core_init = pci_epf_test_core_init, + .link_up = pci_epf_test_link_up, +}; + static int pci_epf_test_alloc_space(struct pci_epf *epf) { struct pci_epf_test *epf_test = epf_get_drvdata(epf); @@ -881,12 +872,8 @@ static int pci_epf_test_bind(struct pci_epf *epf) if (ret) epf_test->dma_supported = false; - if (linkup_notifier || core_init_notifier) { - epf->nb.notifier_call = pci_epf_test_notifier; - pci_epc_register_notifier(epc, &epf->nb); - } else { + if (!linkup_notifier && !core_init_notifier) queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work); - } return 0; } diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 805f3d64f93b..a51ba9f158c3 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -690,10 +690,15 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf); */ void pci_epc_linkup(struct pci_epc *epc) { + struct pci_epf *epf; + if (!epc || IS_ERR(epc)) return; - atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); + list_for_each_entry(epf, &epc->pci_epf, list) { + if (epf->event_ops->link_up) + epf->event_ops->link_up(epf); + } } EXPORT_SYMBOL_GPL(pci_epc_linkup); @@ -779,7 +784,6 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, mutex_init(&epc->lock); INIT_LIST_HEAD(&epc->pci_epf); - ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier); device_initialize(&epc->dev); epc->dev.class = pci_epc_class; diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index a48778e1a4ee..05604fe0ede0 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -134,7 +134,6 @@ struct pci_epc_mem { * @group: configfs group representing the PCI EPC device * @lock: mutex to protect pci_epc ops * @function_num_map: bitmap to manage physical function number - * @notifier: used to notify EPF of any EPC events (like linkup) */ struct pci_epc { struct device dev; @@ -149,7 +148,6 @@ struct pci_epc { /* mutex to protect against concurrent access of EP controller */ struct mutex lock; unsigned long function_num_map; - struct atomic_notifier_head notifier; }; /** @@ -192,12 +190,6 @@ static inline void *epc_get_drvdata(struct pci_epc *epc) return dev_get_drvdata(&epc->dev); } -static inline int -pci_epc_register_notifier(struct pci_epc *epc, struct notifier_block *nb) -{ - return atomic_notifier_chain_register(&epc->notifier, nb); -} - struct pci_epc * __devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, struct module *owner); diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index a06f3b4c8bee..bc613f0df7e3 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -17,10 +17,6 @@ struct pci_epf; enum pci_epc_interface_type; -enum pci_notify_event { - LINK_UP, -}; - enum pci_barno { NO_BAR = -1, BAR_0, @@ -74,9 +70,11 @@ struct pci_epf_ops { /** * struct pci_epf_event_ops - Callbacks for capturing the EPC events * @core_init: Callback for the EPC initialization complete event + * @link_up: Callback for the EPC link up event */ struct pci_epc_event_ops { int (*core_init)(struct pci_epf *epf); + int (*link_up)(struct pci_epf *epf); }; /** @@ -135,7 +133,6 @@ struct pci_epf_bar { * @driver: the EPF driver to which this EPF device is bound * @id: Pointer to the EPF device ID * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc - * @nb: notifier block to notify EPF of any EPC events (like linkup) * @lock: mutex to protect pci_epf_ops * @sec_epc: the secondary EPC device to which this EPF device is bound * @sec_epc_list: to add pci_epf as list of PCI endpoint functions to secondary @@ -164,7 +161,6 @@ struct pci_epf { struct pci_epf_driver *driver; const struct pci_epf_device_id *id; struct list_head list; - struct notifier_block nb; /* mutex to protect against concurrent access of pci_epf_ops */ struct mutex lock;
As a part of the transition towards callback mechanism for signalling the events from EPC to EPF, let's use the link_up() callback in the place of the LINK_UP notifier. This also removes the notifier support completely from the PCI endpoint framework. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> --- drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++------------- drivers/pci/endpoint/pci-epc-core.c | 8 +++-- include/linux/pci-epc.h | 8 ----- include/linux/pci-epf.h | 8 ++--- 4 files changed, 18 insertions(+), 39 deletions(-)