2022-11-11 14:25:11

by Thomas Gleixner

[permalink] [raw]
Subject: [patch 23/39] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

From: Ahmed S. Darwish <[email protected]>

To distangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_alloc_irq_vectors_affinity() and let its kernel-doc reference
pci_alloc_irq_vectors() documentation added in parent commit.

Signed-off-by: Ahmed S. Darwish <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>

---
drivers/pci/msi/api.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++-
drivers/pci/msi/msi.c | 65 +----------------------------------------------------
2 files changed, 59 insertions(+), 65 deletions(-)
---
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index 1714905943fb..8546749afa6e 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -123,3 +123,62 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
flags, NULL);
}
EXPORT_SYMBOL(pci_alloc_irq_vectors);
+
+/**
+ * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
+ * vectors with affinity requirements
+ * @dev: the PCI device to operate on
+ * @min_vecs: minimum required number of vectors (must be >= 1)
+ * @max_vecs: maximum desired number of vectors
+ * @flags: allocation flags, as in pci_alloc_irq_vectors()
+ * @affd: affinity requirements (can be %NULL).
+ *
+ * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
+ * Check that function docs, and &struct irq_affinity, for more details.
+ */
+int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags,
+ struct irq_affinity *affd)
+{
+ struct irq_affinity msi_default_affd = {0};
+ int nvecs = -ENOSPC;
+
+ if (flags & PCI_IRQ_AFFINITY) {
+ if (!affd)
+ affd = &msi_default_affd;
+ } else {
+ if (WARN_ON(affd))
+ affd = NULL;
+ }
+
+ if (flags & PCI_IRQ_MSIX) {
+ nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
+ affd, flags);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ if (flags & PCI_IRQ_MSI) {
+ nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ /* use legacy IRQ if allowed */
+ if (flags & PCI_IRQ_LEGACY) {
+ if (min_vecs == 1 && dev->irq) {
+ /*
+ * Invoke the affinity spreading logic to ensure that
+ * the device driver can adjust queue configuration
+ * for the single interrupt case.
+ */
+ if (affd)
+ irq_create_affinity_masks(1, affd);
+ pci_intx(dev, 1);
+ return 1;
+ }
+ }
+
+ return nvecs;
+}
+EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 6700ef1c734e..a028774f438d 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -887,71 +887,6 @@ int __pci_enable_msix_range(struct pci_dev *dev,
}

/**
- * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
- * @dev: PCI device to operate on
- * @min_vecs: minimum number of vectors required (must be >= 1)
- * @max_vecs: maximum (desired) number of vectors
- * @flags: flags or quirks for the allocation
- * @affd: optional description of the affinity requirements
- *
- * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
- * vectors if available, and fall back to a single legacy vector
- * if neither is available. Return the number of vectors allocated,
- * (which might be smaller than @max_vecs) if successful, or a negative
- * error code on error. If less than @min_vecs interrupt vectors are
- * available for @dev the function will fail with -ENOSPC.
- *
- * To get the Linux IRQ number used for a vector that can be passed to
- * request_irq() use the pci_irq_vector() helper.
- */
-int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
- unsigned int max_vecs, unsigned int flags,
- struct irq_affinity *affd)
-{
- struct irq_affinity msi_default_affd = {0};
- int nvecs = -ENOSPC;
-
- if (flags & PCI_IRQ_AFFINITY) {
- if (!affd)
- affd = &msi_default_affd;
- } else {
- if (WARN_ON(affd))
- affd = NULL;
- }
-
- if (flags & PCI_IRQ_MSIX) {
- nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
- affd, flags);
- if (nvecs > 0)
- return nvecs;
- }
-
- if (flags & PCI_IRQ_MSI) {
- nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
- if (nvecs > 0)
- return nvecs;
- }
-
- /* use legacy IRQ if allowed */
- if (flags & PCI_IRQ_LEGACY) {
- if (min_vecs == 1 && dev->irq) {
- /*
- * Invoke the affinity spreading logic to ensure that
- * the device driver can adjust queue configuration
- * for the single interrupt case.
- */
- if (affd)
- irq_create_affinity_masks(1, affd);
- pci_intx(dev, 1);
- return 1;
- }
- }
-
- return nvecs;
-}
-EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
-
-/**
* pci_free_irq_vectors - free previously allocated IRQs for a device
* @dev: PCI device to operate on
*



2022-11-16 16:52:52

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [patch 23/39] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

On Fri, Nov 11, 2022 at 02:54:51PM +0100, Thomas Gleixner wrote:
> From: Ahmed S. Darwish <[email protected]>
>
> To distangle the maze in msi.c, all exported device-driver MSI APIs are
> now to be grouped in one file, api.c.
>
> Move pci_alloc_irq_vectors_affinity() and let its kernel-doc reference
> pci_alloc_irq_vectors() documentation added in parent commit.
>
> Signed-off-by: Ahmed S. Darwish <[email protected]>
> Signed-off-by: Thomas Gleixner <[email protected]>

Acked-by: Bjorn Helgaas <[email protected]>

One question below.

> ---
> drivers/pci/msi/api.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++-
> drivers/pci/msi/msi.c | 65 +----------------------------------------------------
> 2 files changed, 59 insertions(+), 65 deletions(-)
> ---
> diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
> index 1714905943fb..8546749afa6e 100644
> --- a/drivers/pci/msi/api.c
> +++ b/drivers/pci/msi/api.c
> @@ -123,3 +123,62 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> flags, NULL);
> }
> EXPORT_SYMBOL(pci_alloc_irq_vectors);
> +
> +/**
> + * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
> + * vectors with affinity requirements
> + * @dev: the PCI device to operate on
> + * @min_vecs: minimum required number of vectors (must be >= 1)
> + * @max_vecs: maximum desired number of vectors
> + * @flags: allocation flags, as in pci_alloc_irq_vectors()
> + * @affd: affinity requirements (can be %NULL).
> + *
> + * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
> + * Check that function docs, and &struct irq_affinity, for more details.

Is "&struct irq_affinity" some kernel-doc syntax, or is the "&"
superfluous?

> + */
> +int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
> + unsigned int max_vecs, unsigned int flags,
> + struct irq_affinity *affd)
> +{
> + struct irq_affinity msi_default_affd = {0};
> + int nvecs = -ENOSPC;
> +
> + if (flags & PCI_IRQ_AFFINITY) {
> + if (!affd)
> + affd = &msi_default_affd;
> + } else {
> + if (WARN_ON(affd))
> + affd = NULL;
> + }
> +
> + if (flags & PCI_IRQ_MSIX) {
> + nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
> + affd, flags);
> + if (nvecs > 0)
> + return nvecs;
> + }
> +
> + if (flags & PCI_IRQ_MSI) {
> + nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
> + if (nvecs > 0)
> + return nvecs;
> + }
> +
> + /* use legacy IRQ if allowed */
> + if (flags & PCI_IRQ_LEGACY) {
> + if (min_vecs == 1 && dev->irq) {
> + /*
> + * Invoke the affinity spreading logic to ensure that
> + * the device driver can adjust queue configuration
> + * for the single interrupt case.
> + */
> + if (affd)
> + irq_create_affinity_masks(1, affd);
> + pci_intx(dev, 1);
> + return 1;
> + }
> + }
> +
> + return nvecs;
> +}
> +EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
> diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
> index 6700ef1c734e..a028774f438d 100644
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -887,71 +887,6 @@ int __pci_enable_msix_range(struct pci_dev *dev,
> }
>
> /**
> - * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
> - * @dev: PCI device to operate on
> - * @min_vecs: minimum number of vectors required (must be >= 1)
> - * @max_vecs: maximum (desired) number of vectors
> - * @flags: flags or quirks for the allocation
> - * @affd: optional description of the affinity requirements
> - *
> - * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
> - * vectors if available, and fall back to a single legacy vector
> - * if neither is available. Return the number of vectors allocated,
> - * (which might be smaller than @max_vecs) if successful, or a negative
> - * error code on error. If less than @min_vecs interrupt vectors are
> - * available for @dev the function will fail with -ENOSPC.
> - *
> - * To get the Linux IRQ number used for a vector that can be passed to
> - * request_irq() use the pci_irq_vector() helper.
> - */
> -int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
> - unsigned int max_vecs, unsigned int flags,
> - struct irq_affinity *affd)
> -{
> - struct irq_affinity msi_default_affd = {0};
> - int nvecs = -ENOSPC;
> -
> - if (flags & PCI_IRQ_AFFINITY) {
> - if (!affd)
> - affd = &msi_default_affd;
> - } else {
> - if (WARN_ON(affd))
> - affd = NULL;
> - }
> -
> - if (flags & PCI_IRQ_MSIX) {
> - nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
> - affd, flags);
> - if (nvecs > 0)
> - return nvecs;
> - }
> -
> - if (flags & PCI_IRQ_MSI) {
> - nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
> - if (nvecs > 0)
> - return nvecs;
> - }
> -
> - /* use legacy IRQ if allowed */
> - if (flags & PCI_IRQ_LEGACY) {
> - if (min_vecs == 1 && dev->irq) {
> - /*
> - * Invoke the affinity spreading logic to ensure that
> - * the device driver can adjust queue configuration
> - * for the single interrupt case.
> - */
> - if (affd)
> - irq_create_affinity_masks(1, affd);
> - pci_intx(dev, 1);
> - return 1;
> - }
> - }
> -
> - return nvecs;
> -}
> -EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
> -
> -/**
> * pci_free_irq_vectors - free previously allocated IRQs for a device
> * @dev: PCI device to operate on
> *
>

2022-11-16 17:43:41

by Thomas Gleixner

[permalink] [raw]
Subject: Re: [patch 23/39] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

On Wed, Nov 16 2022 at 10:23, Bjorn Helgaas wrote:
> On Fri, Nov 11, 2022 at 02:54:51PM +0100, Thomas Gleixner wrote:
>> + * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
>> + * Check that function docs, and &struct irq_affinity, for more details.
>
> Is "&struct irq_affinity" some kernel-doc syntax, or is the "&"
> superfluous?

The latter.

Subject: [tip: irq/core] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

The following commit has been merged into the irq/core branch of tip:

Commit-ID: beddb5efb43ee5b1c048e49225f75b03f8d36aac
Gitweb: https://git.kernel.org/tip/beddb5efb43ee5b1c048e49225f75b03f8d36aac
Author: Ahmed S. Darwish <[email protected]>
AuthorDate: Fri, 11 Nov 2022 14:54:51 +01:00
Committer: Thomas Gleixner <[email protected]>
CommitterDate: Thu, 17 Nov 2022 15:15:20 +01:00

PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_alloc_irq_vectors_affinity() and let its kernel-doc reference
pci_alloc_irq_vectors() documentation added in parent commit.

Signed-off-by: Ahmed S. Darwish <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Bjorn Helgaas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]


---
drivers/pci/msi/api.c | 59 ++++++++++++++++++++++++++++++++++++++-
drivers/pci/msi/msi.c | 65 +------------------------------------------
2 files changed, 59 insertions(+), 65 deletions(-)

diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index 1714905..8546749 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -123,3 +123,62 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
flags, NULL);
}
EXPORT_SYMBOL(pci_alloc_irq_vectors);
+
+/**
+ * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
+ * vectors with affinity requirements
+ * @dev: the PCI device to operate on
+ * @min_vecs: minimum required number of vectors (must be >= 1)
+ * @max_vecs: maximum desired number of vectors
+ * @flags: allocation flags, as in pci_alloc_irq_vectors()
+ * @affd: affinity requirements (can be %NULL).
+ *
+ * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
+ * Check that function docs, and &struct irq_affinity, for more details.
+ */
+int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags,
+ struct irq_affinity *affd)
+{
+ struct irq_affinity msi_default_affd = {0};
+ int nvecs = -ENOSPC;
+
+ if (flags & PCI_IRQ_AFFINITY) {
+ if (!affd)
+ affd = &msi_default_affd;
+ } else {
+ if (WARN_ON(affd))
+ affd = NULL;
+ }
+
+ if (flags & PCI_IRQ_MSIX) {
+ nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
+ affd, flags);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ if (flags & PCI_IRQ_MSI) {
+ nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
+ if (nvecs > 0)
+ return nvecs;
+ }
+
+ /* use legacy IRQ if allowed */
+ if (flags & PCI_IRQ_LEGACY) {
+ if (min_vecs == 1 && dev->irq) {
+ /*
+ * Invoke the affinity spreading logic to ensure that
+ * the device driver can adjust queue configuration
+ * for the single interrupt case.
+ */
+ if (affd)
+ irq_create_affinity_masks(1, affd);
+ pci_intx(dev, 1);
+ return 1;
+ }
+ }
+
+ return nvecs;
+}
+EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 6700ef1..a028774 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -887,71 +887,6 @@ int __pci_enable_msix_range(struct pci_dev *dev,
}

/**
- * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
- * @dev: PCI device to operate on
- * @min_vecs: minimum number of vectors required (must be >= 1)
- * @max_vecs: maximum (desired) number of vectors
- * @flags: flags or quirks for the allocation
- * @affd: optional description of the affinity requirements
- *
- * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
- * vectors if available, and fall back to a single legacy vector
- * if neither is available. Return the number of vectors allocated,
- * (which might be smaller than @max_vecs) if successful, or a negative
- * error code on error. If less than @min_vecs interrupt vectors are
- * available for @dev the function will fail with -ENOSPC.
- *
- * To get the Linux IRQ number used for a vector that can be passed to
- * request_irq() use the pci_irq_vector() helper.
- */
-int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
- unsigned int max_vecs, unsigned int flags,
- struct irq_affinity *affd)
-{
- struct irq_affinity msi_default_affd = {0};
- int nvecs = -ENOSPC;
-
- if (flags & PCI_IRQ_AFFINITY) {
- if (!affd)
- affd = &msi_default_affd;
- } else {
- if (WARN_ON(affd))
- affd = NULL;
- }
-
- if (flags & PCI_IRQ_MSIX) {
- nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
- affd, flags);
- if (nvecs > 0)
- return nvecs;
- }
-
- if (flags & PCI_IRQ_MSI) {
- nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
- if (nvecs > 0)
- return nvecs;
- }
-
- /* use legacy IRQ if allowed */
- if (flags & PCI_IRQ_LEGACY) {
- if (min_vecs == 1 && dev->irq) {
- /*
- * Invoke the affinity spreading logic to ensure that
- * the device driver can adjust queue configuration
- * for the single interrupt case.
- */
- if (affd)
- irq_create_affinity_masks(1, affd);
- pci_intx(dev, 1);
- return 1;
- }
- }
-
- return nvecs;
-}
-EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
-
-/**
* pci_free_irq_vectors - free previously allocated IRQs for a device
* @dev: PCI device to operate on
*

2022-11-18 13:40:14

by Ahmed S. Darwish

[permalink] [raw]
Subject: Re: [patch 23/39] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

On Wed, Nov 16, 2022 at 10:23:22AM -0600, Bjorn Helgaas wrote:
> On Fri, Nov 11, 2022 at 02:54:51PM +0100, Thomas Gleixner wrote:
...
> > +
> > +/**
> > + * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
> > + * vectors with affinity requirements
> > + * @dev: the PCI device to operate on
> > + * @min_vecs: minimum required number of vectors (must be >= 1)
> > + * @max_vecs: maximum desired number of vectors
> > + * @flags: allocation flags, as in pci_alloc_irq_vectors()
> > + * @affd: affinity requirements (can be %NULL).
> > + *
> > + * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
> > + * Check that function docs, and &struct irq_affinity, for more details.
>
> Is "&struct irq_affinity" some kernel-doc syntax, or is the "&"
> superfluous?
>

Hmmm, I stole it from Documentation/doc-guide/kernel-doc.rst. htmldoc
parses it and generates a link to the referenced structure's kernel-doc.

But, yeah, this was literally the first usage of such a doc pattern in
the entire kernel's C code :)

Thanks,

--
Ahmed S. Darwish
Linutronix GmbH

2022-11-18 13:47:11

by Peter Zijlstra

[permalink] [raw]
Subject: Re: [patch 23/39] PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c

On Fri, Nov 18, 2022 at 01:34:12PM +0100, Ahmed S. Darwish wrote:
> On Wed, Nov 16, 2022 at 10:23:22AM -0600, Bjorn Helgaas wrote:
> > On Fri, Nov 11, 2022 at 02:54:51PM +0100, Thomas Gleixner wrote:
> ...
> > > +
> > > +/**
> > > + * pci_alloc_irq_vectors_affinity() - Allocate multiple device interrupt
> > > + * vectors with affinity requirements
> > > + * @dev: the PCI device to operate on
> > > + * @min_vecs: minimum required number of vectors (must be >= 1)
> > > + * @max_vecs: maximum desired number of vectors
> > > + * @flags: allocation flags, as in pci_alloc_irq_vectors()
> > > + * @affd: affinity requirements (can be %NULL).
> > > + *
> > > + * Same as pci_alloc_irq_vectors(), but with the extra @affd parameter.
> > > + * Check that function docs, and &struct irq_affinity, for more details.
> >
> > Is "&struct irq_affinity" some kernel-doc syntax, or is the "&"
> > superfluous?
> >
>
> Hmmm, I stole it from Documentation/doc-guide/kernel-doc.rst. htmldoc
> parses it and generates a link to the referenced structure's kernel-doc.
>
> But, yeah, this was literally the first usage of such a doc pattern in
> the entire kernel's C code :)

Perhaps then not start with it and instead try and convince John to make
his script more clever -- this same script already recognises functions
by their () suffix, might as well also key off the 'struct' keyword, no?

This is a Code comment, to be read in a text editor. That & is a syntax
error.