Provide a standard debug function for use throughout the driver.
Signed-off-by: Ben Widawsky <[email protected]>
---
drivers/cxl/cxl.h | 3 +++
drivers/cxl/mem.c | 26 +++++++++++++++++++++++++-
2 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 77c2dee6843c..e5afb89dab0b 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -9,6 +9,9 @@
#include <linux/bitops.h>
#include <linux/io.h>
+#define cxl_debug(fmt, ...) \
+ pr_debug("CXL DEBUG: %s: " fmt, __func__, ##__VA_ARGS__)
+
#define CXL_SET_FIELD(value, field) \
({ \
WARN_ON(!FIELD_FIT(field##_MASK, value)); \
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index a2cea7ac7cc6..6b2f8d3776b5 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -122,9 +122,12 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
{
const int timeout = msecs_to_jiffies(2000);
const unsigned long start = jiffies;
+ unsigned long end = start;
while (cxl_doorbell_busy(cxlm)) {
- if (time_after(jiffies, start + timeout)) {
+ end = jiffies;
+
+ if (time_after(end, start + timeout)) {
/* Check again in case preempted before timeout test */
if (!cxl_doorbell_busy(cxlm))
break;
@@ -133,6 +136,8 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
cpu_relax();
}
+ cxl_debug("Doorbell wait took %dms",
+ jiffies_to_msecs(end) - jiffies_to_msecs(start));
return 0;
}
@@ -180,6 +185,8 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm,
}
/* #4 */
+ cxl_debug("Sending command to %s\n",
+ dev_driver_string(&cxlm->pdev->dev));
cxl_write_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET,
CXLDEV_MB_CTRL_DOORBELL);
@@ -308,6 +315,8 @@ static int cxl_mem_open(struct inode *inode, struct file *file)
if (!cxlmd)
return -ENXIO;
+ cxl_debug("Opened %pD\n", file);
+
file->private_data = cxlmd;
return 0;
@@ -383,6 +392,10 @@ static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd,
.size_in = cmd->info.size_in,
.size_out = size_out,
};
+ cxl_debug("Submitting command for user\n"
+ "\topcode: %x\n"
+ "\tsize: %zub/%zub\n",
+ mbox_cmd.opcode, mbox_cmd.size_in, mbox_cmd.size_out);
rc = cxl_mem_mbox_send_cmd(cxlmd->cxlm, &mbox_cmd);
cxl_mem_mbox_put(cxlmd->cxlm);
if (rc)
@@ -479,6 +492,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
u32 n_commands;
int i, j;
+ cxl_debug("Query IOCTL\n");
+
if (get_user(n_commands, (u32 __user *)arg))
return -EFAULT;
@@ -511,6 +526,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
struct cxl_mem_command c;
int rc;
+ cxl_debug("Send IOCTL\n");
+
rc = cxl_validate_cmd_from_user(u, &c);
if (rc)
return rc;
@@ -843,6 +860,13 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
id = (struct cxl_mbox_identify *)mbox_cmd.payload;
+ cxl_debug("Driver identify command\n"
+ "\tFirmware Version: %s\n"
+ "\tTotal Capacity: %llu (%llu persistent)\n"
+ "\tLSA size: %u\n",
+ id->fw_revision, id->total_capacity, id->persistent_capacity,
+ id->lsa_size);
+
/*
* TODO: enumerate DPA map, as 'ram' and 'pmem' do not alias.
* For now, only the capacity is exported in sysfs
--
2.29.2
On Tue, Dec 8, 2020 at 4:24 PM Ben Widawsky <[email protected]> wrote:
>
> Provide a standard debug function for use throughout the driver.
>
> Signed-off-by: Ben Widawsky <[email protected]>
> ---
> drivers/cxl/cxl.h | 3 +++
> drivers/cxl/mem.c | 26 +++++++++++++++++++++++++-
> 2 files changed, 28 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 77c2dee6843c..e5afb89dab0b 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -9,6 +9,9 @@
> #include <linux/bitops.h>
> #include <linux/io.h>
>
> +#define cxl_debug(fmt, ...) \
> + pr_debug("CXL DEBUG: %s: " fmt, __func__, ##__VA_ARGS__)
> +
This should be dev_dbg(), then you don't need the CXL DEBUG prefix. In
fact you don't need a cxl_debug() macro at all in that case. cxl_mem
might need a ->dev attribute for this purpose.
> #define CXL_SET_FIELD(value, field) \
> ({ \
> WARN_ON(!FIELD_FIT(field##_MASK, value)); \
> diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> index a2cea7ac7cc6..6b2f8d3776b5 100644
> --- a/drivers/cxl/mem.c
> +++ b/drivers/cxl/mem.c
> @@ -122,9 +122,12 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> {
> const int timeout = msecs_to_jiffies(2000);
> const unsigned long start = jiffies;
> + unsigned long end = start;
>
> while (cxl_doorbell_busy(cxlm)) {
> - if (time_after(jiffies, start + timeout)) {
> + end = jiffies;
> +
> + if (time_after(end, start + timeout)) {
> /* Check again in case preempted before timeout test */
> if (!cxl_doorbell_busy(cxlm))
> break;
> @@ -133,6 +136,8 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> cpu_relax();
> }
>
> + cxl_debug("Doorbell wait took %dms",
> + jiffies_to_msecs(end) - jiffies_to_msecs(start));
> return 0;
> }
>
> @@ -180,6 +185,8 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm,
> }
>
> /* #4 */
> + cxl_debug("Sending command to %s\n",
> + dev_driver_string(&cxlm->pdev->dev));
dev_dbg() already includes dev_driver_string().
> cxl_write_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET,
> CXLDEV_MB_CTRL_DOORBELL);
>
> @@ -308,6 +315,8 @@ static int cxl_mem_open(struct inode *inode, struct file *file)
> if (!cxlmd)
> return -ENXIO;
>
> + cxl_debug("Opened %pD\n", file);
> +
> file->private_data = cxlmd;
>
> return 0;
> @@ -383,6 +392,10 @@ static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd,
> .size_in = cmd->info.size_in,
> .size_out = size_out,
> };
> + cxl_debug("Submitting command for user\n"
> + "\topcode: %x\n"
> + "\tsize: %zub/%zub\n",
> + mbox_cmd.opcode, mbox_cmd.size_in, mbox_cmd.size_out);
> rc = cxl_mem_mbox_send_cmd(cxlmd->cxlm, &mbox_cmd);
> cxl_mem_mbox_put(cxlmd->cxlm);
> if (rc)
> @@ -479,6 +492,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> u32 n_commands;
> int i, j;
>
> + cxl_debug("Query IOCTL\n");
> +
> if (get_user(n_commands, (u32 __user *)arg))
> return -EFAULT;
>
> @@ -511,6 +526,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> struct cxl_mem_command c;
> int rc;
>
> + cxl_debug("Send IOCTL\n");
> +
> rc = cxl_validate_cmd_from_user(u, &c);
> if (rc)
> return rc;
> @@ -843,6 +860,13 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
>
> id = (struct cxl_mbox_identify *)mbox_cmd.payload;
>
> + cxl_debug("Driver identify command\n"
> + "\tFirmware Version: %s\n"
> + "\tTotal Capacity: %llu (%llu persistent)\n"
> + "\tLSA size: %u\n",
> + id->fw_revision, id->total_capacity, id->persistent_capacity,
> + id->lsa_size);
> +
Seems not necessary for details that are published in sysfs?
On 20-12-08 17:17:36, Dan Williams wrote:
> On Tue, Dec 8, 2020 at 4:24 PM Ben Widawsky <[email protected]> wrote:
> >
> > Provide a standard debug function for use throughout the driver.
> >
> > Signed-off-by: Ben Widawsky <[email protected]>
> > ---
> > drivers/cxl/cxl.h | 3 +++
> > drivers/cxl/mem.c | 26 +++++++++++++++++++++++++-
> > 2 files changed, 28 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> > index 77c2dee6843c..e5afb89dab0b 100644
> > --- a/drivers/cxl/cxl.h
> > +++ b/drivers/cxl/cxl.h
> > @@ -9,6 +9,9 @@
> > #include <linux/bitops.h>
> > #include <linux/io.h>
> >
> > +#define cxl_debug(fmt, ...) \
> > + pr_debug("CXL DEBUG: %s: " fmt, __func__, ##__VA_ARGS__)
> > +
>
> This should be dev_dbg(), then you don't need the CXL DEBUG prefix. In
> fact you don't need a cxl_debug() macro at all in that case. cxl_mem
> might need a ->dev attribute for this purpose.
>
I really like the ability to turn specific messages on and off at will. (FWIW,
__func__ is also redundant because pr_debug allows you to specify a flag to
always print the function name). While it's not very frequent events here, in
the future it likely will be and I think it can be really helpful to be able to
have that level of control.
If you want to avoid creating a new debug functionality, I'm okay with that, but
I'd really like to use pr_debug instead of dev_dbg for those messages going
forward. Once you take that step, it seems giving contributors a macro named
'cxl_debug' so they don't have to figure out when to use what, makes sense. My
mental separation is, dev_* is useful primarily for errors and initialization
debug messaging, pr_debug/trace_printk is for runtime things.
I probably should have put that in the commit message...
> > #define CXL_SET_FIELD(value, field) \
> > ({ \
> > WARN_ON(!FIELD_FIT(field##_MASK, value)); \
> > diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> > index a2cea7ac7cc6..6b2f8d3776b5 100644
> > --- a/drivers/cxl/mem.c
> > +++ b/drivers/cxl/mem.c
> > @@ -122,9 +122,12 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> > {
> > const int timeout = msecs_to_jiffies(2000);
> > const unsigned long start = jiffies;
> > + unsigned long end = start;
> >
> > while (cxl_doorbell_busy(cxlm)) {
> > - if (time_after(jiffies, start + timeout)) {
> > + end = jiffies;
> > +
> > + if (time_after(end, start + timeout)) {
> > /* Check again in case preempted before timeout test */
> > if (!cxl_doorbell_busy(cxlm))
> > break;
> > @@ -133,6 +136,8 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> > cpu_relax();
> > }
> >
> > + cxl_debug("Doorbell wait took %dms",
> > + jiffies_to_msecs(end) - jiffies_to_msecs(start));
> > return 0;
> > }
> >
> > @@ -180,6 +185,8 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm,
> > }
> >
> > /* #4 */
> > + cxl_debug("Sending command to %s\n",
> > + dev_driver_string(&cxlm->pdev->dev));
>
> dev_dbg() already includes dev_driver_string().
>
> > cxl_write_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET,
> > CXLDEV_MB_CTRL_DOORBELL);
> >
> > @@ -308,6 +315,8 @@ static int cxl_mem_open(struct inode *inode, struct file *file)
> > if (!cxlmd)
> > return -ENXIO;
> >
> > + cxl_debug("Opened %pD\n", file);
> > +
> > file->private_data = cxlmd;
> >
> > return 0;
> > @@ -383,6 +392,10 @@ static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd,
> > .size_in = cmd->info.size_in,
> > .size_out = size_out,
> > };
> > + cxl_debug("Submitting command for user\n"
> > + "\topcode: %x\n"
> > + "\tsize: %zub/%zub\n",
> > + mbox_cmd.opcode, mbox_cmd.size_in, mbox_cmd.size_out);
> > rc = cxl_mem_mbox_send_cmd(cxlmd->cxlm, &mbox_cmd);
> > cxl_mem_mbox_put(cxlmd->cxlm);
> > if (rc)
> > @@ -479,6 +492,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> > u32 n_commands;
> > int i, j;
> >
> > + cxl_debug("Query IOCTL\n");
> > +
> > if (get_user(n_commands, (u32 __user *)arg))
> > return -EFAULT;
> >
> > @@ -511,6 +526,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> > struct cxl_mem_command c;
> > int rc;
> >
> > + cxl_debug("Send IOCTL\n");
> > +
> > rc = cxl_validate_cmd_from_user(u, &c);
> > if (rc)
> > return rc;
> > @@ -843,6 +860,13 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
> >
> > id = (struct cxl_mbox_identify *)mbox_cmd.payload;
> >
> > + cxl_debug("Driver identify command\n"
> > + "\tFirmware Version: %s\n"
> > + "\tTotal Capacity: %llu (%llu persistent)\n"
> > + "\tLSA size: %u\n",
> > + id->fw_revision, id->total_capacity, id->persistent_capacity,
> > + id->lsa_size);
> > +
>
> Seems not necessary for details that are published in sysfs?
I was thinking for cases where driver doesn't bind, seeing the identify
information could be useful. This is one case where dev_dbg would also serve
IMO.
On Tue, Dec 8, 2020 at 6:04 PM Ben Widawsky <[email protected]> wrote:
>
> On 20-12-08 17:17:36, Dan Williams wrote:
> > On Tue, Dec 8, 2020 at 4:24 PM Ben Widawsky <[email protected]> wrote:
> > >
> > > Provide a standard debug function for use throughout the driver.
> > >
> > > Signed-off-by: Ben Widawsky <[email protected]>
> > > ---
> > > drivers/cxl/cxl.h | 3 +++
> > > drivers/cxl/mem.c | 26 +++++++++++++++++++++++++-
> > > 2 files changed, 28 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> > > index 77c2dee6843c..e5afb89dab0b 100644
> > > --- a/drivers/cxl/cxl.h
> > > +++ b/drivers/cxl/cxl.h
> > > @@ -9,6 +9,9 @@
> > > #include <linux/bitops.h>
> > > #include <linux/io.h>
> > >
> > > +#define cxl_debug(fmt, ...) \
> > > + pr_debug("CXL DEBUG: %s: " fmt, __func__, ##__VA_ARGS__)
> > > +
> >
> > This should be dev_dbg(), then you don't need the CXL DEBUG prefix. In
> > fact you don't need a cxl_debug() macro at all in that case. cxl_mem
> > might need a ->dev attribute for this purpose.
> >
>
> I really like the ability to turn specific messages on and off at will. (FWIW,
> __func__ is also redundant because pr_debug allows you to specify a flag to
> always print the function name). While it's not very frequent events here, in
> the future it likely will be and I think it can be really helpful to be able to
> have that level of control.
>
> If you want to avoid creating a new debug functionality, I'm okay with that, but
> I'd really like to use pr_debug instead of dev_dbg for those messages going
> forward. Once you take that step, it seems giving contributors a macro named
> 'cxl_debug' so they don't have to figure out when to use what, makes sense. My
> mental separation is, dev_* is useful primarily for errors and initialization
> debug messaging, pr_debug/trace_printk is for runtime things.
>
> I probably should have put that in the commit message...
I suspect you haven't taken a look at the backed and of pr_debug() and
dev_dbg() in a while? They both use _dynamic_func_call and enjoy all
the benefits afforded by /sys/debug/dynamic_debug/control and the
"dyndbg" module option for adding __func__ and enable / disable by
line number or format message . pr_debug() and this cxl_debug() macro
are completely superseded by dev_dbg(). Even if a driver wanted a
common prefix on all prints there is the "#define dev_fmt ..."
mechanism for that.
>
> > > #define CXL_SET_FIELD(value, field) \
> > > ({ \
> > > WARN_ON(!FIELD_FIT(field##_MASK, value)); \
> > > diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> > > index a2cea7ac7cc6..6b2f8d3776b5 100644
> > > --- a/drivers/cxl/mem.c
> > > +++ b/drivers/cxl/mem.c
> > > @@ -122,9 +122,12 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> > > {
> > > const int timeout = msecs_to_jiffies(2000);
> > > const unsigned long start = jiffies;
> > > + unsigned long end = start;
> > >
> > > while (cxl_doorbell_busy(cxlm)) {
> > > - if (time_after(jiffies, start + timeout)) {
> > > + end = jiffies;
> > > +
> > > + if (time_after(end, start + timeout)) {
> > > /* Check again in case preempted before timeout test */
> > > if (!cxl_doorbell_busy(cxlm))
> > > break;
> > > @@ -133,6 +136,8 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
> > > cpu_relax();
> > > }
> > >
> > > + cxl_debug("Doorbell wait took %dms",
> > > + jiffies_to_msecs(end) - jiffies_to_msecs(start));
> > > return 0;
> > > }
> > >
> > > @@ -180,6 +185,8 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm,
> > > }
> > >
> > > /* #4 */
> > > + cxl_debug("Sending command to %s\n",
> > > + dev_driver_string(&cxlm->pdev->dev));
> >
> > dev_dbg() already includes dev_driver_string().
> >
> > > cxl_write_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET,
> > > CXLDEV_MB_CTRL_DOORBELL);
> > >
> > > @@ -308,6 +315,8 @@ static int cxl_mem_open(struct inode *inode, struct file *file)
> > > if (!cxlmd)
> > > return -ENXIO;
> > >
> > > + cxl_debug("Opened %pD\n", file);
> > > +
> > > file->private_data = cxlmd;
> > >
> > > return 0;
> > > @@ -383,6 +392,10 @@ static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd,
> > > .size_in = cmd->info.size_in,
> > > .size_out = size_out,
> > > };
> > > + cxl_debug("Submitting command for user\n"
> > > + "\topcode: %x\n"
> > > + "\tsize: %zub/%zub\n",
> > > + mbox_cmd.opcode, mbox_cmd.size_in, mbox_cmd.size_out);
> > > rc = cxl_mem_mbox_send_cmd(cxlmd->cxlm, &mbox_cmd);
> > > cxl_mem_mbox_put(cxlmd->cxlm);
> > > if (rc)
> > > @@ -479,6 +492,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> > > u32 n_commands;
> > > int i, j;
> > >
> > > + cxl_debug("Query IOCTL\n");
> > > +
> > > if (get_user(n_commands, (u32 __user *)arg))
> > > return -EFAULT;
> > >
> > > @@ -511,6 +526,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
> > > struct cxl_mem_command c;
> > > int rc;
> > >
> > > + cxl_debug("Send IOCTL\n");
> > > +
> > > rc = cxl_validate_cmd_from_user(u, &c);
> > > if (rc)
> > > return rc;
> > > @@ -843,6 +860,13 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
> > >
> > > id = (struct cxl_mbox_identify *)mbox_cmd.payload;
> > >
> > > + cxl_debug("Driver identify command\n"
> > > + "\tFirmware Version: %s\n"
> > > + "\tTotal Capacity: %llu (%llu persistent)\n"
> > > + "\tLSA size: %u\n",
> > > + id->fw_revision, id->total_capacity, id->persistent_capacity,
> > > + id->lsa_size);
> > > +
> >
> > Seems not necessary for details that are published in sysfs?
>
> I was thinking for cases where driver doesn't bind, seeing the identify
> information could be useful. This is one case where dev_dbg would also serve
> IMO.
There's very little that can cause bind failures after
cxl_mem_identify() succeeds. The bind failures themselves will
dev_err() the reason.