When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
use bounce buffers") was introduced, it did not add the logic
for tracing the bounce buffer usage from iommu_dma_map_page().
All of the users of swiotlb_tbl_map_single() trace their bounce
buffer usage, except iommu_dma_map_page(). This makes it difficult
to track SWIOTLB usage from that function. Thus, trace bounce buffer
usage from iommu_dma_map_page().
Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
Cc: [email protected] # v5.15+
Cc: Tom Murphy <[email protected]>
Cc: Lu Baolu <[email protected]>
Cc: Saravana Kannan <[email protected]>
Signed-off-by: Isaac J. Manjarres <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>
(cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
Signed-off-by: Isaac J. Manjarres <[email protected]>
---
drivers/iommu/dma-iommu.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 48c6f7ff4aef..8cd63e6ccd2c 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -25,6 +25,7 @@
#include <linux/vmalloc.h>
#include <linux/crash_dump.h>
#include <linux/dma-direct.h>
+#include <trace/events/swiotlb.h>
struct iommu_dma_msi_page {
struct list_head list;
@@ -817,6 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
void *padding_start;
size_t padding_size, aligned_size;
+ trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
+
aligned_size = iova_align(iovad, size);
phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size,
iova_mask(iovad), dir, attrs);
--
2.43.0.429.g432eaa2c6b-goog
On Mon, Jan 22, 2024 at 12:37:54PM -0800, Isaac J. Manjarres wrote:
> When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
> use bounce buffers") was introduced, it did not add the logic
> for tracing the bounce buffer usage from iommu_dma_map_page().
>
> All of the users of swiotlb_tbl_map_single() trace their bounce
> buffer usage, except iommu_dma_map_page(). This makes it difficult
> to track SWIOTLB usage from that function. Thus, trace bounce buffer
> usage from iommu_dma_map_page().
>
> Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
> Cc: [email protected] # v5.15+
> Cc: Tom Murphy <[email protected]>
> Cc: Lu Baolu <[email protected]>
> Cc: Saravana Kannan <[email protected]>
> Signed-off-by: Isaac J. Manjarres <[email protected]>
> Link: https://lore.kernel.org/r/[email protected]
> Signed-off-by: Joerg Roedel <[email protected]>
> (cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
> Signed-off-by: Isaac J. Manjarres <[email protected]>
Now queued up, thanks.
greg k-h
On Mon, Jan 22, 2024 at 12:37:54PM -0800, Isaac J. Manjarres wrote:
> When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
> use bounce buffers") was introduced, it did not add the logic
> for tracing the bounce buffer usage from iommu_dma_map_page().
>
> All of the users of swiotlb_tbl_map_single() trace their bounce
> buffer usage, except iommu_dma_map_page(). This makes it difficult
> to track SWIOTLB usage from that function. Thus, trace bounce buffer
> usage from iommu_dma_map_page().
>
> Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
> Cc: [email protected] # v5.15+
> Cc: Tom Murphy <[email protected]>
> Cc: Lu Baolu <[email protected]>
> Cc: Saravana Kannan <[email protected]>
> Signed-off-by: Isaac J. Manjarres <[email protected]>
> Link: https://lore.kernel.org/r/[email protected]
> Signed-off-by: Joerg Roedel <[email protected]>
> (cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
> Signed-off-by: Isaac J. Manjarres <[email protected]>
> ---
> drivers/iommu/dma-iommu.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> index 48c6f7ff4aef..8cd63e6ccd2c 100644
> --- a/drivers/iommu/dma-iommu.c
> +++ b/drivers/iommu/dma-iommu.c
> @@ -25,6 +25,7 @@
> #include <linux/vmalloc.h>
> #include <linux/crash_dump.h>
> #include <linux/dma-direct.h>
> +#include <trace/events/swiotlb.h>
>
> struct iommu_dma_msi_page {
> struct list_head list;
> @@ -817,6 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
> void *padding_start;
> size_t padding_size, aligned_size;
>
> + trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
> +
Hi, this backported patch trying to access swiotlb_force variable is
causing a build conflict where CONFIG_SWIOTLB is not enabled.
In file included from kernel/drivers/iommu/dma-iommu.c:28:
kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
enum swiotlb_force swiotlb_force),
^
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
^
In file included from kernel/drivers/iommu/dma-iommu.c:28:
kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
^
In file included from kernel/drivers/iommu/dma-iommu.c:28:
kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
^
In file included from kernel/drivers/iommu/dma-iommu.c:28:
kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
^
kernel/drivers/iommu/dma-iommu.c:865:42: error: argument type 'enum SWIOTLB_NO_FORCE' is incomplete
trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
^~~~~~~~~~~~~
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
^~~~~~~~~~~~~~~~
kernel/include/trace/events/swiotlb.h:15:9: note: forward declaration of 'enum SWIOTLB_NO_FORCE'
enum swiotlb_force swiotlb_force),
^
kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
#define swiotlb_force SWIOTLB_NO_FORCE
--------------------------------------------------------------------------------------------------------------------------------------------------
I have a simple proposed fix which can resolve this compile time conflict when CONFIG_SWIOTLB is disabled.
--- a/include/trace/events/swiotlb.h
+++ b/include/trace/events/swiotlb.h
@@ -7,6 +7,7 @@
#include <linux/tracepoint.h>
+#ifdef CONFIG_SWIOTLB
TRACE_EVENT(swiotlb_bounced,
TP_PROTO(struct device *dev,
@@ -43,6 +44,9 @@ TRACE_EVENT(swiotlb_bounced,
{ SWIOTLB_FORCE, "FORCE" },
{ SWIOTLB_NO_FORCE, "NO_FORCE" }))
);
+#else
+#define trace_swiotlb_bounced(dev, phys, size, swiotlb_force)
+#endif /* CONFIG_SWIOTLB */
#endif /* _TRACE_SWIOTLB_H */
Thanks & regards,
Bibek
> aligned_size = iova_align(iovad, size);
> phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size,
> iova_mask(iovad), dir, attrs);
> --
> 2.43.0.429.g432eaa2c6b-goog
>
On Thu, Jun 13, 2024 at 04:01:01PM +0530, Bibek Kumar Patro wrote:
> On Mon, Jan 22, 2024 at 12:37:54PM -0800, Isaac J. Manjarres wrote:
> > When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
> > use bounce buffers") was introduced, it did not add the logic
> > for tracing the bounce buffer usage from iommu_dma_map_page().
> >
> > All of the users of swiotlb_tbl_map_single() trace their bounce
> > buffer usage, except iommu_dma_map_page(). This makes it difficult
> > to track SWIOTLB usage from that function. Thus, trace bounce buffer
> > usage from iommu_dma_map_page().
> >
> > Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
> > Cc: [email protected] # v5.15+
> > Cc: Tom Murphy <[email protected]>
> > Cc: Lu Baolu <[email protected]>
> > Cc: Saravana Kannan <[email protected]>
> > Signed-off-by: Isaac J. Manjarres <[email protected]>
> > Link: https://lore.kernel.org/r/[email protected]
> > Signed-off-by: Joerg Roedel <[email protected]>
> > (cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
> > Signed-off-by: Isaac J. Manjarres <[email protected]>
> > ---
> > drivers/iommu/dma-iommu.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> > index 48c6f7ff4aef..8cd63e6ccd2c 100644
> > --- a/drivers/iommu/dma-iommu.c
> > +++ b/drivers/iommu/dma-iommu.c
> > @@ -25,6 +25,7 @@
> > #include <linux/vmalloc.h>
> > #include <linux/crash_dump.h>
> > #include <linux/dma-direct.h>
> > +#include <trace/events/swiotlb.h>
> >
> > struct iommu_dma_msi_page {
> > struct list_head list;
> > @@ -817,6 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
> > void *padding_start;
> > size_t padding_size, aligned_size;
> >
> > + trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
> > +
>
> Hi, this backported patch trying to access swiotlb_force variable is
> causing a build conflict where CONFIG_SWIOTLB is not enabled.
>
> In file included from kernel/drivers/iommu/dma-iommu.c:28:
> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> enum swiotlb_force swiotlb_force),
> ^
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
> ^
> In file included from kernel/drivers/iommu/dma-iommu.c:28:
> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
> ^
> In file included from kernel/drivers/iommu/dma-iommu.c:28:
> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
> ^
> In file included from kernel/drivers/iommu/dma-iommu.c:28:
> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
> ^
> kernel/drivers/iommu/dma-iommu.c:865:42: error: argument type 'enum SWIOTLB_NO_FORCE' is incomplete
> trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
> ^~~~~~~~~~~~~
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
> ^~~~~~~~~~~~~~~~
> kernel/include/trace/events/swiotlb.h:15:9: note: forward declaration of 'enum SWIOTLB_NO_FORCE'
> enum swiotlb_force swiotlb_force),
> ^
> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> #define swiotlb_force SWIOTLB_NO_FORCE
>
> --------------------------------------------------------------------------------------------------------------------------------------------------
>
> I have a simple proposed fix which can resolve this compile time conflict when CONFIG_SWIOTLB is disabled.
>
> --- a/include/trace/events/swiotlb.h
> +++ b/include/trace/events/swiotlb.h
> @@ -7,6 +7,7 @@
>
> #include <linux/tracepoint.h>
>
> +#ifdef CONFIG_SWIOTLB
> TRACE_EVENT(swiotlb_bounced,
>
> TP_PROTO(struct device *dev,
> @@ -43,6 +44,9 @@ TRACE_EVENT(swiotlb_bounced,
> { SWIOTLB_FORCE, "FORCE" },
> { SWIOTLB_NO_FORCE, "NO_FORCE" }))
> );
> +#else
> +#define trace_swiotlb_bounced(dev, phys, size, swiotlb_force)
> +#endif /* CONFIG_SWIOTLB */
>
> #endif /* _TRACE_SWIOTLB_H */
>
>
Why not just take whatever change upstream fixes this instead of a
one-off change?
thanks
greg k-h
On 6/13/2024 4:45 PM, Greg KH wrote:
> On Thu, Jun 13, 2024 at 04:01:01PM +0530, Bibek Kumar Patro wrote:
>> On Mon, Jan 22, 2024 at 12:37:54PM -0800, Isaac J. Manjarres wrote:
>>> When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
>>> use bounce buffers") was introduced, it did not add the logic
>>> for tracing the bounce buffer usage from iommu_dma_map_page().
>>>
>>> All of the users of swiotlb_tbl_map_single() trace their bounce
>>> buffer usage, except iommu_dma_map_page(). This makes it difficult
>>> to track SWIOTLB usage from that function. Thus, trace bounce buffer
>>> usage from iommu_dma_map_page().
>>>
>>> Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
>>> Cc: [email protected] # v5.15+
>>> Cc: Tom Murphy <[email protected]>
>>> Cc: Lu Baolu <[email protected]>
>>> Cc: Saravana Kannan <[email protected]>
>>> Signed-off-by: Isaac J. Manjarres <[email protected]>
>>> Link: https://lore.kernel.org/r/[email protected]
>>> Signed-off-by: Joerg Roedel <[email protected]>
>>> (cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
>>> Signed-off-by: Isaac J. Manjarres <[email protected]>
>>> ---
>>> drivers/iommu/dma-iommu.c | 3 +++
>>> 1 file changed, 3 insertions(+)
>>>
>>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
>>> index 48c6f7ff4aef..8cd63e6ccd2c 100644
>>> --- a/drivers/iommu/dma-iommu.c
>>> +++ b/drivers/iommu/dma-iommu.c
>>> @@ -25,6 +25,7 @@
>>> #include <linux/vmalloc.h>
>>> #include <linux/crash_dump.h>
>>> #include <linux/dma-direct.h>
>>> +#include <trace/events/swiotlb.h>
>>>
>>> struct iommu_dma_msi_page {
>>> struct list_head list;
>>> @@ -817,6 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
>>> void *padding_start;
>>> size_t padding_size, aligned_size;
>>>
>>> + trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
>>> +
>>
>> Hi, this backported patch trying to access swiotlb_force variable is
>> causing a build conflict where CONFIG_SWIOTLB is not enabled.
>>
>> In file included from kernel/drivers/iommu/dma-iommu.c:28:
>> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
>> enum swiotlb_force swiotlb_force),
>> ^
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>> ^
>> In file included from kernel/drivers/iommu/dma-iommu.c:28:
>> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>> ^
>> In file included from kernel/drivers/iommu/dma-iommu.c:28:
>> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>> ^
>> In file included from kernel/drivers/iommu/dma-iommu.c:28:
>> kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>> ^
>> kernel/drivers/iommu/dma-iommu.c:865:42: error: argument type 'enum SWIOTLB_NO_FORCE' is incomplete
>> trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
>> ^~~~~~~~~~~~~
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>> ^~~~~~~~~~~~~~~~
>> kernel/include/trace/events/swiotlb.h:15:9: note: forward declaration of 'enum SWIOTLB_NO_FORCE'
>> enum swiotlb_force swiotlb_force),
>> ^
>> kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
>> #define swiotlb_force SWIOTLB_NO_FORCE
>>
>> --------------------------------------------------------------------------------------------------------------------------------------------------
>>
>> I have a simple proposed fix which can resolve this compile time conflict when CONFIG_SWIOTLB is disabled.
>>
>> --- a/include/trace/events/swiotlb.h
>> +++ b/include/trace/events/swiotlb.h
>> @@ -7,6 +7,7 @@
>>
>> #include <linux/tracepoint.h>
>>
>> +#ifdef CONFIG_SWIOTLB
>> TRACE_EVENT(swiotlb_bounced,
>>
>> TP_PROTO(struct device *dev,
>> @@ -43,6 +44,9 @@ TRACE_EVENT(swiotlb_bounced,
>> { SWIOTLB_FORCE, "FORCE" },
>> { SWIOTLB_NO_FORCE, "NO_FORCE" }))
>> );
>> +#else
>> +#define trace_swiotlb_bounced(dev, phys, size, swiotlb_force)
>> +#endif /* CONFIG_SWIOTLB */
>>
>> #endif /* _TRACE_SWIOTLB_H */
>>
>>
>
> Why not just take whatever change upstream fixes this instead of a
> one-off change?
>
I am currently checking the history on swiotlb_force and how it's
removed in latest kernel versions. If those changes are applicable on
this stable branch can we explore backporting those instead of this one-
off change ?
Thanks & regards,
Bibek
> thanks
>
> greg k-h
On Thu, Jun 13, 2024 at 11:10:57PM +0530, Bibek Kumar Patro wrote:
>
>
> On 6/13/2024 4:45 PM, Greg KH wrote:
> > On Thu, Jun 13, 2024 at 04:01:01PM +0530, Bibek Kumar Patro wrote:
> > > On Mon, Jan 22, 2024 at 12:37:54PM -0800, Isaac J. Manjarres wrote:
> > > > When commit 82612d66d51d ("iommu: Allow the dma-iommu api to
> > > > use bounce buffers") was introduced, it did not add the logic
> > > > for tracing the bounce buffer usage from iommu_dma_map_page().
> > > >
> > > > All of the users of swiotlb_tbl_map_single() trace their bounce
> > > > buffer usage, except iommu_dma_map_page(). This makes it difficult
> > > > to track SWIOTLB usage from that function. Thus, trace bounce buffer
> > > > usage from iommu_dma_map_page().
> > > >
> > > > Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
> > > > Cc: [email protected] # v5.15+
> > > > Cc: Tom Murphy <[email protected]>
> > > > Cc: Lu Baolu <[email protected]>
> > > > Cc: Saravana Kannan <[email protected]>
> > > > Signed-off-by: Isaac J. Manjarres <[email protected]>
> > > > Link: https://lore.kernel.org/r/[email protected]
> > > > Signed-off-by: Joerg Roedel <[email protected]>
> > > > (cherry picked from commit a63c357b9fd56ad5fe64616f5b22835252c6a76a)
> > > > Signed-off-by: Isaac J. Manjarres <[email protected]>
> > > > ---
> > > > drivers/iommu/dma-iommu.c | 3 +++
> > > > 1 file changed, 3 insertions(+)
> > > >
> > > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> > > > index 48c6f7ff4aef..8cd63e6ccd2c 100644
> > > > --- a/drivers/iommu/dma-iommu.c
> > > > +++ b/drivers/iommu/dma-iommu.c
> > > > @@ -25,6 +25,7 @@
> > > > #include <linux/vmalloc.h>
> > > > #include <linux/crash_dump.h>
> > > > #include <linux/dma-direct.h>
> > > > +#include <trace/events/swiotlb.h>
> > > > struct iommu_dma_msi_page {
> > > > struct list_head list;
> > > > @@ -817,6 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
> > > > void *padding_start;
> > > > size_t padding_size, aligned_size;
> > > > + trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
> > > > +
> > >
> > > Hi, this backported patch trying to access swiotlb_force variable is
> > > causing a build conflict where CONFIG_SWIOTLB is not enabled.
> > >
> > > In file included from kernel/drivers/iommu/dma-iommu.c:28:
> > > kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> > > enum swiotlb_force swiotlb_force),
> > > ^
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > > ^
> > > In file included from kernel/drivers/iommu/dma-iommu.c:28:
> > > kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > > ^
> > > In file included from kernel/drivers/iommu/dma-iommu.c:28:
> > > kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > > ^
> > > In file included from kernel/drivers/iommu/dma-iommu.c:28:
> > > kernel/include/trace/events/swiotlb.h:15:9: error: declaration of 'enum SWIOTLB_NO_FORCE' will not be visible outside of this function [-Werror,-Wvisibility]
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > > ^
> > > kernel/drivers/iommu/dma-iommu.c:865:42: error: argument type 'enum SWIOTLB_NO_FORCE' is incomplete
> > > trace_swiotlb_bounced(dev, phys, size, swiotlb_force);
> > > ^~~~~~~~~~~~~
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > > ^~~~~~~~~~~~~~~~
> > > kernel/include/trace/events/swiotlb.h:15:9: note: forward declaration of 'enum SWIOTLB_NO_FORCE'
> > > enum swiotlb_force swiotlb_force),
> > > ^
> > > kernel/include/linux/swiotlb.h:143:23: note: expanded from macro 'swiotlb_force'
> > > #define swiotlb_force SWIOTLB_NO_FORCE
> > >
> > > --------------------------------------------------------------------------------------------------------------------------------------------------
> > >
> > > I have a simple proposed fix which can resolve this compile time conflict when CONFIG_SWIOTLB is disabled.
> > >
> > > --- a/include/trace/events/swiotlb.h
> > > +++ b/include/trace/events/swiotlb.h
> > > @@ -7,6 +7,7 @@
> > >
> > > #include <linux/tracepoint.h>
> > >
> > > +#ifdef CONFIG_SWIOTLB
> > > TRACE_EVENT(swiotlb_bounced,
> > >
> > > TP_PROTO(struct device *dev,
> > > @@ -43,6 +44,9 @@ TRACE_EVENT(swiotlb_bounced,
> > > { SWIOTLB_FORCE, "FORCE" },
> > > { SWIOTLB_NO_FORCE, "NO_FORCE" }))
> > > );
> > > +#else
> > > +#define trace_swiotlb_bounced(dev, phys, size, swiotlb_force)
> > > +#endif /* CONFIG_SWIOTLB */
> > >
> > > #endif /* _TRACE_SWIOTLB_H */
> > >
> > >
> >
> > Why not just take whatever change upstream fixes this instead of a
> > one-off change?
> >
>
> I am currently checking the history on swiotlb_force and how it's
> removed in latest kernel versions. If those changes are applicable on
> this stable branch can we explore backporting those instead of this one-
> off change ?
Please backport what is in the tree already.