RE: [PATCH v12 14/20] cxl/pci: Map RCH downstream AER registers for logging protocol errors

From: Dan Williams
Date: Fri Oct 27 2023 - 23:23:42 EST


Dan Williams wrote:
> Robert Richter wrote:
> > @@ -730,6 +731,38 @@ static bool cxl_handle_endpoint_ras(struct cxl_dev_state *cxlds)
> >
> > #ifdef CONFIG_PCIEAER_CXL
>
> Here is more code in an ifdef block that has no compile time dependency
> on the config symbol. Please do not use ifdef blocks for runtime
> dependencies.
>
> Again, this will need to be a post -rc1 cleanup.

Here is that patch:

-- >8 --
Subject: PCI/AER: Increase compile coverage of CONFIG_PCIEAER_CXL implementation

From: Dan Williams <dan.j.williams@xxxxxxxxx>

Per coding-style, avoid usage of conditional compilation for
CONFIG_PCIEAER_CXL related helpers. Instead use
IS_ENABLED(CONFIG_PCIEAER_CXL) to check when CXL error handling is
compile-time disabled.

Cc: Terry Bowman <terry.bowman@xxxxxxx>
Cc: Robert Richter <rrichter@xxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/cxl/core/pci.c | 9 +++------
drivers/cxl/cxl.h | 6 ------
drivers/pci/pcie/aer.c | 15 +++++----------
3 files changed, 8 insertions(+), 22 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 3da195caa4ad..2d7ba1899ea2 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -729,8 +729,6 @@ static bool cxl_handle_endpoint_ras(struct cxl_dev_state *cxlds)
return __cxl_handle_ras(cxlds, cxlds->regs.ras);
}

-#ifdef CONFIG_PCIEAER_CXL
-
static void cxl_dport_map_rch_aer(struct cxl_dport *dport)
{
struct cxl_rcrb_info *ri = &dport->rcrb;
@@ -797,6 +795,9 @@ void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport)
struct device *dport_dev = dport->dport_dev;
struct pci_host_bridge *host_bridge;

+ if (!IS_ENABLED(CONFIG_PCIEAER_CXL))
+ return;
+
host_bridge = to_pci_host_bridge(dport_dev);
if (host_bridge->native_cxl_error)
dport->rcrb.aer_cap = cxl_rcrb_to_aer(dport_dev, dport->rcrb.base);
@@ -897,10 +898,6 @@ static void cxl_handle_rdport_errors(struct cxl_dev_state *cxlds)
cxl_handle_rdport_ras(cxlds, dport);
}

-#else
-static void cxl_handle_rdport_errors(struct cxl_dev_state *cxlds) { }
-#endif
-
void cxl_cor_error_detected(struct pci_dev *pdev)
{
struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 378fc96ff7ff..0bf0d13346c2 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -712,13 +712,7 @@ struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
struct device *dport_dev, int port_id,
resource_size_t rcrb);
-
-#ifdef CONFIG_PCIEAER_CXL
void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport);
-#else
-static inline void cxl_setup_parent_dport(struct device *host,
- struct cxl_dport *dport) { }
-#endif

struct cxl_decoder *to_cxl_decoder(struct device *dev);
struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 41076cb2956e..36541bfab688 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -934,8 +934,6 @@ static bool find_source_device(struct pci_dev *parent,
return true;
}

-#ifdef CONFIG_PCIEAER_CXL
-
/**
* pci_aer_unmask_internal_errors - unmask internal errors
* @dev: pointer to the pcie_dev data structure
@@ -1000,7 +998,8 @@ static int cxl_rch_handle_error_iter(struct pci_dev *dev, void *data)
struct aer_err_info *info = (struct aer_err_info *)data;
const struct pci_error_handlers *err_handler;

- if (!is_cxl_mem_dev(dev) || !cxl_error_is_native(dev))
+ if (!is_cxl_mem_dev(dev) || !cxl_error_is_native(dev) ||
+ !IS_ENABLED(CONFIG_PCIEAER_CXL))
return 0;

/* protect dev->driver */
@@ -1041,7 +1040,9 @@ static int handles_cxl_error_iter(struct pci_dev *dev, void *data)
bool *handles_cxl = data;

if (!*handles_cxl)
- *handles_cxl = is_cxl_mem_dev(dev) && cxl_error_is_native(dev);
+ *handles_cxl = is_cxl_mem_dev(dev) &&
+ cxl_error_is_native(dev) &&
+ IS_ENABLED(CONFIG_PCIEAER_CXL);

/* Non-zero terminates iteration */
return *handles_cxl;
@@ -1067,12 +1068,6 @@ static void cxl_rch_enable_rcec(struct pci_dev *rcec)
pci_info(rcec, "CXL: Internal errors unmasked");
}

-#else
-static inline void cxl_rch_enable_rcec(struct pci_dev *dev) { }
-static inline void cxl_rch_handle_error(struct pci_dev *dev,
- struct aer_err_info *info) { }
-#endif
-
/**
* pci_aer_handle_error - handle logging error into an event log
* @dev: pointer to pci_dev data structure of error source device