| Message ID | 20201209002418.1976362-13-ben.widawsky@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | CXL 2.0 Support | expand |
On 20-12-08 19:06:46, Dan Williams wrote: > On Tue, Dec 8, 2020 at 6:04 PM Ben Widawsky <ben.widawsky@intel.com> wrote: > > > > On 20-12-08 17:17:36, Dan Williams wrote: > > > On Tue, Dec 8, 2020 at 4:24 PM Ben Widawsky <ben.widawsky@intel.com> wrote: > > > > > > > > Provide a standard debug function for use throughout the driver. > > > > > > > > Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> > > > > --- > > > > 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. > In that case, I'm just going to squash in the debug messages into the various commits that need them. > > > > > > #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.
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
Provide a standard debug function for use throughout the driver. Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> --- drivers/cxl/cxl.h | 3 +++ drivers/cxl/mem.c | 26 +++++++++++++++++++++++++- 2 files changed, 28 insertions(+), 1 deletion(-)