| Message ID | 164298422000.3018233.4106867312927858722.stgit@dwillia2-desk3.amr.corp.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | CXL.mem Topology Discovery and Hotplug Support | expand |
On Sun, 23 Jan 2022 16:30:20 -0800 Dan Williams <dan.j.williams@intel.com> wrote: > In preparation for moving dport enumeration into the core, require the > port device lock to be acquired by the caller. > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> Why does it make sense to drop the cxl_device_lock() lockdep stuff in the paths affected here? > --- > drivers/cxl/acpi.c | 2 ++ > drivers/cxl/core/port.c | 3 +-- > tools/testing/cxl/mock_acpi.c | 4 ++++ > 3 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c > index ab2b76532272..e596dc375267 100644 > --- a/drivers/cxl/acpi.c > +++ b/drivers/cxl/acpi.c > @@ -342,7 +342,9 @@ static int add_host_bridge_dport(struct device *match, void *arg) > return 0; > } > > + device_lock(&root_port->dev); > rc = cxl_add_dport(root_port, match, uid, ctx.chbcr); > + device_unlock(&root_port->dev); > if (rc) { > dev_err(host, "failed to add downstream port: %s\n", > dev_name(match)); > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c > index ec9587e52423..c51a10154e29 100644 > --- a/drivers/cxl/core/port.c > +++ b/drivers/cxl/core/port.c > @@ -516,7 +516,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > { > struct cxl_dport *dup; > > - cxl_device_lock(&port->dev); > + device_lock_assert(&port->dev); > dup = find_dport(port, new->port_id); > if (dup) > dev_err(&port->dev, > @@ -525,7 +525,6 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > dev_name(dup->dport)); > else > list_add_tail(&new->list, &port->dports); > - cxl_device_unlock(&port->dev); > > return dup ? -EEXIST : 0; > } > diff --git a/tools/testing/cxl/mock_acpi.c b/tools/testing/cxl/mock_acpi.c > index 4c8a493ace56..667c032ccccf 100644 > --- a/tools/testing/cxl/mock_acpi.c > +++ b/tools/testing/cxl/mock_acpi.c > @@ -57,7 +57,9 @@ static int match_add_root_port(struct pci_dev *pdev, void *data) > > /* TODO walk DVSEC to find component register base */ > port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); > + device_lock(&port->dev); > rc = cxl_add_dport(port, &pdev->dev, port_num, CXL_RESOURCE_NONE); > + device_unlock(&port->dev); > if (rc) { > dev_err(dev, "failed to add dport: %s (%d)\n", > dev_name(&pdev->dev), rc); > @@ -78,7 +80,9 @@ static int mock_add_root_port(struct platform_device *pdev, void *data) > struct device *dev = ctx->dev; > int rc; > > + device_lock(&port->dev); > rc = cxl_add_dport(port, &pdev->dev, pdev->id, CXL_RESOURCE_NONE); > + device_unlock(&port->dev); > if (rc) { > dev_err(dev, "failed to add dport: %s (%d)\n", > dev_name(&pdev->dev), rc); >
On 22-01-23 16:30:20, Dan Williams wrote: > In preparation for moving dport enumeration into the core, require the > port device lock to be acquired by the caller. > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > --- > drivers/cxl/acpi.c | 2 ++ > drivers/cxl/core/port.c | 3 +-- > tools/testing/cxl/mock_acpi.c | 4 ++++ > 3 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c > index ab2b76532272..e596dc375267 100644 > --- a/drivers/cxl/acpi.c > +++ b/drivers/cxl/acpi.c > @@ -342,7 +342,9 @@ static int add_host_bridge_dport(struct device *match, void *arg) > return 0; > } > > + device_lock(&root_port->dev); > rc = cxl_add_dport(root_port, match, uid, ctx.chbcr); > + device_unlock(&root_port->dev); > if (rc) { > dev_err(host, "failed to add downstream port: %s\n", > dev_name(match)); > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c > index ec9587e52423..c51a10154e29 100644 > --- a/drivers/cxl/core/port.c > +++ b/drivers/cxl/core/port.c > @@ -516,7 +516,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > { > struct cxl_dport *dup; > > - cxl_device_lock(&port->dev); > + device_lock_assert(&port->dev); > dup = find_dport(port, new->port_id); > if (dup) > dev_err(&port->dev, > @@ -525,7 +525,6 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > dev_name(dup->dport)); > else > list_add_tail(&new->list, &port->dports); > - cxl_device_unlock(&port->dev); > > return dup ? -EEXIST : 0; > } > diff --git a/tools/testing/cxl/mock_acpi.c b/tools/testing/cxl/mock_acpi.c > index 4c8a493ace56..667c032ccccf 100644 > --- a/tools/testing/cxl/mock_acpi.c > +++ b/tools/testing/cxl/mock_acpi.c > @@ -57,7 +57,9 @@ static int match_add_root_port(struct pci_dev *pdev, void *data) > > /* TODO walk DVSEC to find component register base */ > port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); > + device_lock(&port->dev); > rc = cxl_add_dport(port, &pdev->dev, port_num, CXL_RESOURCE_NONE); > + device_unlock(&port->dev); > if (rc) { > dev_err(dev, "failed to add dport: %s (%d)\n", > dev_name(&pdev->dev), rc); > @@ -78,7 +80,9 @@ static int mock_add_root_port(struct platform_device *pdev, void *data) > struct device *dev = ctx->dev; > int rc; > > + device_lock(&port->dev); > rc = cxl_add_dport(port, &pdev->dev, pdev->id, CXL_RESOURCE_NONE); > + device_unlock(&port->dev); > if (rc) { > dev_err(dev, "failed to add dport: %s (%d)\n", > dev_name(&pdev->dev), rc); > Since I really don't understand, perhaps an explanation as to why you aren't using cxl_device_lock would help? (Is it just to get around not having a cxl_device_lock_assert())?
On Mon, Jan 31, 2022 at 3:47 PM Ben Widawsky <ben.widawsky@intel.com> wrote: > > On 22-01-23 16:30:20, Dan Williams wrote: > > In preparation for moving dport enumeration into the core, require the > > port device lock to be acquired by the caller. > > > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > > --- > > drivers/cxl/acpi.c | 2 ++ > > drivers/cxl/core/port.c | 3 +-- > > tools/testing/cxl/mock_acpi.c | 4 ++++ > > 3 files changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c > > index ab2b76532272..e596dc375267 100644 > > --- a/drivers/cxl/acpi.c > > +++ b/drivers/cxl/acpi.c > > @@ -342,7 +342,9 @@ static int add_host_bridge_dport(struct device *match, void *arg) > > return 0; > > } > > > > + device_lock(&root_port->dev); > > rc = cxl_add_dport(root_port, match, uid, ctx.chbcr); > > + device_unlock(&root_port->dev); > > if (rc) { > > dev_err(host, "failed to add downstream port: %s\n", > > dev_name(match)); > > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c > > index ec9587e52423..c51a10154e29 100644 > > --- a/drivers/cxl/core/port.c > > +++ b/drivers/cxl/core/port.c > > @@ -516,7 +516,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > > { > > struct cxl_dport *dup; > > > > - cxl_device_lock(&port->dev); > > + device_lock_assert(&port->dev); > > dup = find_dport(port, new->port_id); > > if (dup) > > dev_err(&port->dev, > > @@ -525,7 +525,6 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) > > dev_name(dup->dport)); > > else > > list_add_tail(&new->list, &port->dports); > > - cxl_device_unlock(&port->dev); > > > > return dup ? -EEXIST : 0; > > } > > diff --git a/tools/testing/cxl/mock_acpi.c b/tools/testing/cxl/mock_acpi.c > > index 4c8a493ace56..667c032ccccf 100644 > > --- a/tools/testing/cxl/mock_acpi.c > > +++ b/tools/testing/cxl/mock_acpi.c > > @@ -57,7 +57,9 @@ static int match_add_root_port(struct pci_dev *pdev, void *data) > > > > /* TODO walk DVSEC to find component register base */ > > port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); > > + device_lock(&port->dev); > > rc = cxl_add_dport(port, &pdev->dev, port_num, CXL_RESOURCE_NONE); > > + device_unlock(&port->dev); > > if (rc) { > > dev_err(dev, "failed to add dport: %s (%d)\n", > > dev_name(&pdev->dev), rc); > > @@ -78,7 +80,9 @@ static int mock_add_root_port(struct platform_device *pdev, void *data) > > struct device *dev = ctx->dev; > > int rc; > > > > + device_lock(&port->dev); > > rc = cxl_add_dport(port, &pdev->dev, pdev->id, CXL_RESOURCE_NONE); > > + device_unlock(&port->dev); > > if (rc) { > > dev_err(dev, "failed to add dport: %s (%d)\n", > > dev_name(&pdev->dev), rc); > > > > Since I really don't understand, perhaps an explanation as to why you aren't > using cxl_device_lock would help? (Is it just to get around not having a > cxl_device_lock_assert())? Whoops, this gets fixed up later on in , but I rebased this patch and didn't notice that I inadvertently dropped the lockdep stuff. Will rebase this hiccup out of the history.
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c index ab2b76532272..e596dc375267 100644 --- a/drivers/cxl/acpi.c +++ b/drivers/cxl/acpi.c @@ -342,7 +342,9 @@ static int add_host_bridge_dport(struct device *match, void *arg) return 0; } + device_lock(&root_port->dev); rc = cxl_add_dport(root_port, match, uid, ctx.chbcr); + device_unlock(&root_port->dev); if (rc) { dev_err(host, "failed to add downstream port: %s\n", dev_name(match)); diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index ec9587e52423..c51a10154e29 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -516,7 +516,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) { struct cxl_dport *dup; - cxl_device_lock(&port->dev); + device_lock_assert(&port->dev); dup = find_dport(port, new->port_id); if (dup) dev_err(&port->dev, @@ -525,7 +525,6 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) dev_name(dup->dport)); else list_add_tail(&new->list, &port->dports); - cxl_device_unlock(&port->dev); return dup ? -EEXIST : 0; } diff --git a/tools/testing/cxl/mock_acpi.c b/tools/testing/cxl/mock_acpi.c index 4c8a493ace56..667c032ccccf 100644 --- a/tools/testing/cxl/mock_acpi.c +++ b/tools/testing/cxl/mock_acpi.c @@ -57,7 +57,9 @@ static int match_add_root_port(struct pci_dev *pdev, void *data) /* TODO walk DVSEC to find component register base */ port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); + device_lock(&port->dev); rc = cxl_add_dport(port, &pdev->dev, port_num, CXL_RESOURCE_NONE); + device_unlock(&port->dev); if (rc) { dev_err(dev, "failed to add dport: %s (%d)\n", dev_name(&pdev->dev), rc); @@ -78,7 +80,9 @@ static int mock_add_root_port(struct platform_device *pdev, void *data) struct device *dev = ctx->dev; int rc; + device_lock(&port->dev); rc = cxl_add_dport(port, &pdev->dev, pdev->id, CXL_RESOURCE_NONE); + device_unlock(&port->dev); if (rc) { dev_err(dev, "failed to add dport: %s (%d)\n", dev_name(&pdev->dev), rc);
In preparation for moving dport enumeration into the core, require the port device lock to be acquired by the caller. Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- drivers/cxl/acpi.c | 2 ++ drivers/cxl/core/port.c | 3 +-- tools/testing/cxl/mock_acpi.c | 4 ++++ 3 files changed, 7 insertions(+), 2 deletions(-)