* [RFCv2 0/3] vmd irq list shortening, map allocation
@ 2016-09-02 17:53 Jon Derrick
2016-09-02 17:53 ` [RFCv2 1/3] vmd: eliminate vmd_vector member from list type Jon Derrick
` (4 more replies)
0 siblings, 5 replies; 8+ messages in thread
From: Jon Derrick @ 2016-09-02 17:53 UTC (permalink / raw)
To: helgaas; +Cc: Jon Derrick, keith.busch, linux-pci
V2:
Added a map for vmd irqs to attempt to allocate all vmd irqs within an
irq list into a single page. Once we start getting many devices
sharing the irq in an irq list, this may help the list traversal latency.
V1:
Couple of RFC patches here. I don't really notice a positive benefit but
it does reduce the struct size of vmd_irq_list and hopefully we gain some
cache benefits from that.
Both are based on:
https://patchwork.kernel.org/patch/9304179/
https://patchwork.kernel.org/patch/9304181/
Jon Derrick (3):
vmd: eliminate vmd_vector member from list type
vmd: eliminate index member from irq list
pci/vmd: Create irq map for irq nodes
arch/x86/pci/vmd.c | 94 ++++++++++++++++++++++++++++++++++++++++++------------
1 file changed, 73 insertions(+), 21 deletions(-)
--
1.8.3.1
^ permalink raw reply [flat|nested] 8+ messages in thread
* [RFCv2 1/3] vmd: eliminate vmd_vector member from list type
2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
@ 2016-09-02 17:53 ` Jon Derrick
2016-09-02 17:53 ` [RFCv2 2/3] vmd: eliminate index member from irq list Jon Derrick
` (3 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Jon Derrick @ 2016-09-02 17:53 UTC (permalink / raw)
To: helgaas; +Cc: Jon Derrick, keith.busch, linux-pci
Eliminate unused vmd and vector members from vmd_irq_list and discover
the vector using pci_irq_vector().
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
---
arch/x86/pci/vmd.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c
index 4c0eac7..9320216 100644
--- a/arch/x86/pci/vmd.c
+++ b/arch/x86/pci/vmd.c
@@ -58,15 +58,12 @@ struct vmd_irq {
/**
* struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
* @irq_list: the list of irq's the VMD one demuxes to.
- * @vmd_vector: the h/w IRQ assigned to the VMD.
* @index: index into the VMD MSI-X table; used for message routing.
* @count: number of child IRQs assigned to this vector; used to track
* sharing.
*/
struct vmd_irq_list {
struct list_head irq_list;
- struct vmd_dev *vmd;
- unsigned int vmd_vector;
unsigned int index;
unsigned int count;
};
@@ -207,8 +204,10 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
vmdirq->irq = vmd_next_irq(vmd, desc);
vmdirq->virq = virq;
- irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip,
- vmdirq, handle_untracked_irq, vmd, NULL);
+ irq_domain_set_info(domain, virq,
+ pci_irq_vector(vmd->dev, vmdirq->irq->index),
+ info->chip, vmdirq,
+ handle_untracked_irq, vmd, NULL);
return 0;
}
@@ -690,10 +689,8 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
for (i = 0; i < vmd->msix_count; i++) {
INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
- vmd->irqs[i].vmd_vector = pci_irq_vector(dev, i);
vmd->irqs[i].index = i;
-
- err = devm_request_irq(&dev->dev, vmd->irqs[i].vmd_vector,
+ err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
vmd_irq, 0, "vmd", &vmd->irqs[i]);
if (err)
return err;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [RFCv2 2/3] vmd: eliminate index member from irq list
2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
2016-09-02 17:53 ` [RFCv2 1/3] vmd: eliminate vmd_vector member from list type Jon Derrick
@ 2016-09-02 17:53 ` Jon Derrick
2016-09-02 17:53 ` [RFCv2 3/3] pci/vmd: Create irq map for irq nodes Jon Derrick
` (2 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Jon Derrick @ 2016-09-02 17:53 UTC (permalink / raw)
To: helgaas; +Cc: Jon Derrick, keith.busch, linux-pci
Use math to discover the irq list index number relative to the irq list
head.
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
---
arch/x86/pci/vmd.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c
index 9320216..aa8d74e 100644
--- a/arch/x86/pci/vmd.c
+++ b/arch/x86/pci/vmd.c
@@ -58,13 +58,11 @@ struct vmd_irq {
/**
* struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
* @irq_list: the list of irq's the VMD one demuxes to.
- * @index: index into the VMD MSI-X table; used for message routing.
* @count: number of child IRQs assigned to this vector; used to track
* sharing.
*/
struct vmd_irq_list {
struct list_head irq_list;
- unsigned int index;
unsigned int count;
};
@@ -93,6 +91,12 @@ static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
return container_of(bus->sysdata, struct vmd_dev, sysdata);
}
+static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
+ struct vmd_irq_list *irqs)
+{
+ return irqs - vmd->irqs;
+}
+
/*
* Drivers managing a device in a VMD domain allocate their own IRQs as before,
* but the MSI entry for the hardware it's driving will be programmed with a
@@ -105,9 +109,11 @@ static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
struct vmd_irq *vmdirq = data->chip_data;
struct vmd_irq_list *irq = vmdirq->irq;
+ struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
msg->address_hi = MSI_ADDR_BASE_HI;
- msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_DEST_ID(irq->index);
+ msg->address_lo = MSI_ADDR_BASE_LO |
+ MSI_ADDR_DEST_ID(index_from_irqs(vmd, irq));
msg->data = 0;
}
@@ -196,6 +202,7 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
struct msi_desc *desc = arg->desc;
struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+ unsigned int index, vector;
if (!vmdirq)
return -ENOMEM;
@@ -203,10 +210,10 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
INIT_LIST_HEAD(&vmdirq->node);
vmdirq->irq = vmd_next_irq(vmd, desc);
vmdirq->virq = virq;
+ index = index_from_irqs(vmd, vmdirq->irq);
+ vector = pci_irq_vector(vmd->dev, index);
- irq_domain_set_info(domain, virq,
- pci_irq_vector(vmd->dev, vmdirq->irq->index),
- info->chip, vmdirq,
+ irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
handle_untracked_irq, vmd, NULL);
return 0;
}
@@ -689,7 +696,6 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
for (i = 0; i < vmd->msix_count; i++) {
INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
- vmd->irqs[i].index = i;
err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
vmd_irq, 0, "vmd", &vmd->irqs[i]);
if (err)
--
1.8.3.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [RFCv2 3/3] pci/vmd: Create irq map for irq nodes
2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
2016-09-02 17:53 ` [RFCv2 1/3] vmd: eliminate vmd_vector member from list type Jon Derrick
2016-09-02 17:53 ` [RFCv2 2/3] vmd: eliminate index member from irq list Jon Derrick
@ 2016-09-02 17:53 ` Jon Derrick
2016-09-13 20:57 ` [RFCv2 0/3] vmd irq list shortening, map allocation Bjorn Helgaas
2016-09-14 20:25 ` Bjorn Helgaas
4 siblings, 0 replies; 8+ messages in thread
From: Jon Derrick @ 2016-09-02 17:53 UTC (permalink / raw)
To: helgaas; +Cc: Jon Derrick, keith.busch, linux-pci
This patch creates an irq map per VMD device msix vector (irq list), and
maps vmdirq nodes into the irq map. The goal is to be able to get a
reference for all vmd_irqs in the vmd_irq_list within a single page.
Each vmd_irq is tracked with the id allocator, and if the id allocation
fails (if many devices are connected), it will fall back to a normal
kzalloc.
Indexing/traversing will still be managed with list primitives, because
we still need the rcu protection.
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
---
arch/x86/pci/vmd.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 59 insertions(+), 10 deletions(-)
diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c
index aa8d74e..c25fb46 100644
--- a/arch/x86/pci/vmd.c
+++ b/arch/x86/pci/vmd.c
@@ -21,6 +21,7 @@
#include <linux/pci.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
+#include <linux/idr.h>
#include <asm/irqdomain.h>
#include <asm/device.h>
@@ -41,8 +42,9 @@ static DEFINE_RAW_SPINLOCK(list_lock);
* @node: list item for parent traversal.
* @rcu: RCU callback item for freeing.
* @irq: back pointer to parent.
- * @enabled: true if driver enabled IRQ
* @virq: the virtual IRQ value provided to the requesting driver.
+ * @instance: ida instance which is the mapping index in the irq map
+ * @enabled: true if driver enabled IRQ
*
* Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
* a VMD IRQ using this structure.
@@ -51,8 +53,10 @@ struct vmd_irq {
struct list_head node;
struct rcu_head rcu;
struct vmd_irq_list *irq;
- bool enabled;
unsigned int virq;
+ int instance;
+ bool enabled;
+ u8 __pad[8];
};
/**
@@ -74,6 +78,9 @@ struct vmd_dev {
int msix_count;
struct vmd_irq_list *irqs;
+ struct vmd_irq *irq_map;
+ struct ida *map_idas;
+#define VMD_IRQS_PER_MAP (PAGE_SIZE / sizeof(struct vmd_irq))
struct pci_sysdata sysdata;
struct resource resources[3];
@@ -96,6 +103,11 @@ static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
{
return irqs - vmd->irqs;
}
+static inline unsigned int index_from_vmd_irq(struct vmd_dev *vmd,
+ struct vmd_irq *vmd_irq)
+{
+ return ((void *)vmd_irq - (void *)vmd->irq_map) / PAGE_SIZE;
+}
/*
* Drivers managing a device in a VMD domain allocate their own IRQs as before,
@@ -201,16 +213,31 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
{
struct msi_desc *desc = arg->desc;
struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
- struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+ struct vmd_irq *vmdirq;
+ struct vmd_irq_list *irq;
unsigned int index, vector;
-
- if (!vmdirq)
- return -ENOMEM;
+ int instance;
+
+ irq = vmd_next_irq(vmd, desc);
+ index = index_from_irqs(vmd, irq);
+ instance = ida_simple_get(&vmd->map_idas[index], 0, VMD_IRQS_PER_MAP,
+ GFP_KERNEL);
+ if (instance < 0) {
+ vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+ if (!vmdirq) {
+ BUG_ON(1);
+ return -ENOMEM;
+ }
+ } else {
+ struct vmd_irq *base = (void *)vmd->irq_map + index * PAGE_SIZE;
+ vmdirq = &base[instance];
+ memset(vmdirq, 0, sizeof(*vmdirq));
+ }
INIT_LIST_HEAD(&vmdirq->node);
- vmdirq->irq = vmd_next_irq(vmd, desc);
+ vmdirq->irq = irq;
vmdirq->virq = virq;
- index = index_from_irqs(vmd, vmdirq->irq);
+ vmdirq->instance = instance;
vector = pci_irq_vector(vmd->dev, index);
irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
@@ -221,6 +248,7 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
static void vmd_msi_free(struct irq_domain *domain,
struct msi_domain_info *info, unsigned int virq)
{
+ struct vmd_dev *vmd = irq_get_handler_data(virq);
struct vmd_irq *vmdirq = irq_get_chip_data(virq);
unsigned long flags;
@@ -229,9 +257,15 @@ static void vmd_msi_free(struct irq_domain *domain,
/* XXX: Potential optimization to rebalance */
raw_spin_lock_irqsave(&list_lock, flags);
vmdirq->irq->count--;
- raw_spin_unlock_irqrestore(&list_lock, flags);
- kfree_rcu(vmdirq, rcu);
+ if (vmdirq->instance < 0) {
+ raw_spin_unlock_irqrestore(&list_lock, flags);
+ kfree_rcu(vmdirq, rcu);
+ } else {
+ unsigned int index = index_from_vmd_irq(vmd, vmdirq);
+ ida_simple_remove(&vmd->map_idas[index], vmdirq->instance);
+ raw_spin_unlock_irqrestore(&list_lock, flags);
+ }
}
static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
@@ -694,8 +728,19 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
if (!vmd->irqs)
return -ENOMEM;
+ /* devm_ doesn't provide the PAGE_SIZE alignment we want */
+ vmd->irq_map = kcalloc(vmd->msix_count, PAGE_SIZE, GFP_KERNEL);
+ if (!vmd->irq_map)
+ return -ENOMEM;
+
+ vmd->map_idas = devm_kcalloc(&dev->dev, vmd->msix_count,
+ sizeof(*vmd->map_idas), GFP_KERNEL);
+ if (!vmd->map_idas)
+ return -ENOMEM;
+
for (i = 0; i < vmd->msix_count; i++) {
INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
+ ida_init(&vmd->map_idas[i]);
err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
vmd_irq, 0, "vmd", &vmd->irqs[i]);
if (err)
@@ -716,12 +761,16 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
static void vmd_remove(struct pci_dev *dev)
{
struct vmd_dev *vmd = pci_get_drvdata(dev);
+ int i;
vmd_detach_resources(vmd);
pci_set_drvdata(dev, NULL);
sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
pci_stop_root_bus(vmd->bus);
pci_remove_root_bus(vmd->bus);
+ for (i = 0; i < vmd->msix_count; i++)
+ ida_destroy(&vmd->map_idas[i]);
+ kfree(vmd->irq_map);
vmd_teardown_dma_ops(vmd);
irq_domain_remove(vmd->irq_domain);
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [RFCv2 0/3] vmd irq list shortening, map allocation
2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
` (2 preceding siblings ...)
2016-09-02 17:53 ` [RFCv2 3/3] pci/vmd: Create irq map for irq nodes Jon Derrick
@ 2016-09-13 20:57 ` Bjorn Helgaas
2016-09-13 22:16 ` Busch, Keith
2016-09-14 20:25 ` Bjorn Helgaas
4 siblings, 1 reply; 8+ messages in thread
From: Bjorn Helgaas @ 2016-09-13 20:57 UTC (permalink / raw)
To: Jon Derrick; +Cc: keith.busch, linux-pci
On Fri, Sep 02, 2016 at 11:53:03AM -0600, Jon Derrick wrote:
> V2:
> Added a map for vmd irqs to attempt to allocate all vmd irqs within an
> irq list into a single page. Once we start getting many devices
> sharing the irq in an irq list, this may help the list traversal latency.
>
> V1:
> Couple of RFC patches here. I don't really notice a positive benefit but
> it does reduce the struct size of vmd_irq_list and hopefully we gain some
> cache benefits from that.
>
> Both are based on:
> https://patchwork.kernel.org/patch/9304179/
> https://patchwork.kernel.org/patch/9304181/
>
> Jon Derrick (3):
> vmd: eliminate vmd_vector member from list type
> vmd: eliminate index member from irq list
> pci/vmd: Create irq map for irq nodes
>
> arch/x86/pci/vmd.c | 94 ++++++++++++++++++++++++++++++++++++++++++------------
> 1 file changed, 73 insertions(+), 21 deletions(-)
These look OK to me, so if Keith acks them I'll merge them.
^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [RFCv2 0/3] vmd irq list shortening, map allocation
2016-09-13 20:57 ` [RFCv2 0/3] vmd irq list shortening, map allocation Bjorn Helgaas
@ 2016-09-13 22:16 ` Busch, Keith
2016-09-14 14:44 ` Jon Derrick
0 siblings, 1 reply; 8+ messages in thread
From: Busch, Keith @ 2016-09-13 22:16 UTC (permalink / raw)
To: Bjorn Helgaas, Derrick, Jonathan; +Cc: linux-pci
Sorry for the delay. I've been looking into these new PCI IRQ API's and fou=
nd an unrelated issue that I stuck myself with working through with Christo=
ph and Thomas. :)
Patches 1/3 and 2/3 look good to me.
I'm not convinced 3/3 is an improvement. At the very least, we don't want t=
o BUG_ON from a failed kmalloc when we can return an appropriate error inst=
ead. I'll take a closer look at 3/3 and get back to Jon with more feedback.
-----Original Message-----=09
From: Bjorn Helgaas [mailto:helgaas@kernel.org]=20
Sent: Tuesday, September 13, 2016 2:58 PM
To: Derrick, Jonathan <jonathan.derrick@intel.com>
Cc: Busch, Keith <keith.busch@intel.com>; linux-pci@vger.kernel.org
Subject: Re: [RFCv2 0/3] vmd irq list shortening, map allocation
On Fri, Sep 02, 2016 at 11:53:03AM -0600, Jon Derrick wrote:
> V2:
> Added a map for vmd irqs to attempt to allocate all vmd irqs within an
> irq list into a single page. Once we start getting many devices
> sharing the irq in an irq list, this may help the list traversal latency.
>=20
> V1:
> Couple of RFC patches here. I don't really notice a positive benefit but
> it does reduce the struct size of vmd_irq_list and hopefully we gain some
> cache benefits from that.
>=20
> Both are based on:
> https://patchwork.kernel.org/patch/9304179/
> https://patchwork.kernel.org/patch/9304181/
>=20
> Jon Derrick (3):
> vmd: eliminate vmd_vector member from list type
> vmd: eliminate index member from irq list
> pci/vmd: Create irq map for irq nodes
>=20
> arch/x86/pci/vmd.c | 94 ++++++++++++++++++++++++++++++++++++++++++------=
------
> 1 file changed, 73 insertions(+), 21 deletions(-)
These look OK to me, so if Keith acks them I'll merge them.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [RFCv2 0/3] vmd irq list shortening, map allocation
2016-09-13 22:16 ` Busch, Keith
@ 2016-09-14 14:44 ` Jon Derrick
0 siblings, 0 replies; 8+ messages in thread
From: Jon Derrick @ 2016-09-14 14:44 UTC (permalink / raw)
To: Busch, Keith; +Cc: Bjorn Helgaas, linux-pci
Hi Keith,
Thanks for the review
On Tue, Sep 13, 2016 at 04:16:19PM -0600, Busch, Keith wrote:
> Sorry for the delay. I've been looking into these new PCI IRQ API's and found an unrelated issue that I stuck myself with working through with Christoph and Thomas. :)
>
> Patches 1/3 and 2/3 look good to me.
>
> I'm not convinced 3/3 is an improvement. At the very least, we don't want to BUG_ON from a failed kmalloc when we can return an appropriate error instead. I'll take a closer look at 3/3 and get back to Jon with more feedback.
>
Yes the BUG_ON was a mistake I would have removed for the next rev. But I agree with you where I am not convinced either. I have been trying to put together a test vehicle to prove that this is actually an improvement, but I have not had much luck yet.
Also, from what I can tell as well, nobody is using ida for indexing into a map, so that would be converted to the bitmap api instead.
I'll follow up in a (long) while when I get the test case figured out and some real results.
If it's not clear yet, 3/3 can be killed :)
>
>
> -----Original Message-----
> From: Bjorn Helgaas [mailto:helgaas@kernel.org]
> Sent: Tuesday, September 13, 2016 2:58 PM
> To: Derrick, Jonathan <jonathan.derrick@intel.com>
> Cc: Busch, Keith <keith.busch@intel.com>; linux-pci@vger.kernel.org
> Subject: Re: [RFCv2 0/3] vmd irq list shortening, map allocation
>
> On Fri, Sep 02, 2016 at 11:53:03AM -0600, Jon Derrick wrote:
> > V2:
> > Added a map for vmd irqs to attempt to allocate all vmd irqs within an
> > irq list into a single page. Once we start getting many devices
> > sharing the irq in an irq list, this may help the list traversal latency.
> >
> > V1:
> > Couple of RFC patches here. I don't really notice a positive benefit but
> > it does reduce the struct size of vmd_irq_list and hopefully we gain some
> > cache benefits from that.
> >
> > Both are based on:
> > https://patchwork.kernel.org/patch/9304179/
> > https://patchwork.kernel.org/patch/9304181/
> >
> > Jon Derrick (3):
> > vmd: eliminate vmd_vector member from list type
> > vmd: eliminate index member from irq list
> > pci/vmd: Create irq map for irq nodes
> >
> > arch/x86/pci/vmd.c | 94 ++++++++++++++++++++++++++++++++++++++++++------------
> > 1 file changed, 73 insertions(+), 21 deletions(-)
>
> These look OK to me, so if Keith acks them I'll merge them.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [RFCv2 0/3] vmd irq list shortening, map allocation
2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
` (3 preceding siblings ...)
2016-09-13 20:57 ` [RFCv2 0/3] vmd irq list shortening, map allocation Bjorn Helgaas
@ 2016-09-14 20:25 ` Bjorn Helgaas
4 siblings, 0 replies; 8+ messages in thread
From: Bjorn Helgaas @ 2016-09-14 20:25 UTC (permalink / raw)
To: Jon Derrick; +Cc: keith.busch, linux-pci
On Fri, Sep 02, 2016 at 11:53:03AM -0600, Jon Derrick wrote:
> V2:
> Added a map for vmd irqs to attempt to allocate all vmd irqs within an
> irq list into a single page. Once we start getting many devices
> sharing the irq in an irq list, this may help the list traversal latency.
>
> V1:
> Couple of RFC patches here. I don't really notice a positive benefit but
> it does reduce the struct size of vmd_irq_list and hopefully we gain some
> cache benefits from that.
>
> Both are based on:
> https://patchwork.kernel.org/patch/9304179/
> https://patchwork.kernel.org/patch/9304181/
>
> Jon Derrick (3):
> vmd: eliminate vmd_vector member from list type
> vmd: eliminate index member from irq list
> pci/vmd: Create irq map for irq nodes
I converted Keith's "looks good to me" to acks on 1/3 and 2/3, applied them
to pci/host-vmd for v4.9, and dropped 3/3 for now. Thanks, guys!
^ permalink raw reply [flat|nested] 8+ messages in thread
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2016-09-02 17:53 [RFCv2 0/3] vmd irq list shortening, map allocation Jon Derrick
2016-09-02 17:53 ` [RFCv2 1/3] vmd: eliminate vmd_vector member from list type Jon Derrick
2016-09-02 17:53 ` [RFCv2 2/3] vmd: eliminate index member from irq list Jon Derrick
2016-09-02 17:53 ` [RFCv2 3/3] pci/vmd: Create irq map for irq nodes Jon Derrick
2016-09-13 20:57 ` [RFCv2 0/3] vmd irq list shortening, map allocation Bjorn Helgaas
2016-09-13 22:16 ` Busch, Keith
2016-09-14 14:44 ` Jon Derrick
2016-09-14 20:25 ` Bjorn Helgaas
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