2024-02-02 09:58:45

by Saravana Kannan

[permalink] [raw]
Subject: [PATCH v2 0/3] fw_devlink overlapping cycles fix

This is mainly a bug fix with a additional logging improvement. Lots of
details in Patch 2/3.

Greg,

Can you please pull these into 6.8-rcX after Xu gives the Tested-by?

Xu,

Can you please test this whole series and give your Tested-by if it
fixes your issue? Also, from now on, to debug cycles you just need to
search for debug level logs with "cycle:" in the message and convert
them all to info level logs.

v1 -> v2:
Patch 3: Tweaked the log messages and the commit text.

Saravana Kannan (3):
driver core: Fix device_link_flag_is_sync_state_only()
driver core: fw_devlink: Improve detection of overlapping cycles
driver core: fw_devlink: Improve logs for cycle detection

drivers/base/core.c | 26 ++++++++++++++++++++------
1 file changed, 20 insertions(+), 6 deletions(-)

--
2.43.0.594.gd9cf4e227d-goog



2024-02-02 10:24:30

by Saravana Kannan

[permalink] [raw]
Subject: [PATCH v2 3/3] driver core: fw_devlink: Improve logs for cycle detection

The links in a cycle are not all logged in a consistent manner or not
logged at all. Make them consistent by adding a "cycle:" string and log all
the link in the cycles (even the child ==> parent dependency) so that it's
easier to debug cycle detection code. Also, mark the start and end of a
cycle so it's easy to tell when multiple cycles are logged back to back.

Signed-off-by: Saravana Kannan <[email protected]>
---
drivers/base/core.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index e3d666461835..9828da9b933c 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -125,7 +125,7 @@ static void __fwnode_link_del(struct fwnode_link *link)
*/
static void __fwnode_link_cycle(struct fwnode_link *link)
{
- pr_debug("%pfwf: Relaxing link with %pfwf\n",
+ pr_debug("%pfwf: cycle: depends on %pfwf\n",
link->consumer, link->supplier);
link->flags |= FWLINK_FLAG_CYCLE;
}
@@ -1945,6 +1945,7 @@ static bool __fw_devlink_relax_cycles(struct device *con,

/* Termination condition. */
if (sup_dev == con) {
+ pr_debug("----- cycle: start -----\n");
ret = true;
goto out;
}
@@ -1976,8 +1977,11 @@ static bool __fw_devlink_relax_cycles(struct device *con,
else
par_dev = fwnode_get_next_parent_dev(sup_handle);

- if (par_dev && __fw_devlink_relax_cycles(con, par_dev->fwnode))
+ if (par_dev && __fw_devlink_relax_cycles(con, par_dev->fwnode)) {
+ pr_debug("%pfwf: cycle: child of %pfwf\n", sup_handle,
+ par_dev->fwnode);
ret = true;
+ }

if (!sup_dev)
goto out;
@@ -1993,6 +1997,8 @@ static bool __fw_devlink_relax_cycles(struct device *con,

if (__fw_devlink_relax_cycles(con,
dev_link->supplier->fwnode)) {
+ pr_debug("%pfwf: cycle: depends on %pfwf\n", sup_handle,
+ dev_link->supplier->fwnode);
fw_devlink_relax_link(dev_link);
dev_link->flags |= DL_FLAG_CYCLE;
ret = true;
@@ -2072,6 +2078,7 @@ static int fw_devlink_create_devlink(struct device *con,
if (__fw_devlink_relax_cycles(con, sup_handle)) {
__fwnode_link_cycle(link);
flags = fw_devlink_get_flags(link->flags);
+ pr_debug("----- cycle: end -----\n");
dev_info(con, "Fixed dependency cycle(s) with %pfwf\n",
sup_handle);
}
--
2.43.0.594.gd9cf4e227d-goog


2024-02-02 10:59:24

by Xu Yang

[permalink] [raw]
Subject: RE: [EXT] [PATCH v2 0/3] fw_devlink overlapping cycles fix

Hi Saravana,

> Subject: [EXT] [PATCH v2 0/3] fw_devlink overlapping cycles fix
>
> This is mainly a bug fix with a additional logging improvement. Lots of
> details in Patch 2/3.
>
> Greg,
>
> Can you please pull these into 6.8-rcX after Xu gives the Tested-by?
>
> Xu,
>
> Can you please test this whole series and give your Tested-by if it
> fixes your issue? Also, from now on, to debug cycles you just need to
> search for debug level logs with "cycle:" in the message and convert
> them all to info level logs.

Okay. I see.

>
> v1 -> v2:
> Patch 3: Tweaked the log messages and the commit text.
>
> Saravana Kannan (3):
> driver core: Fix device_link_flag_is_sync_state_only()
> driver core: fw_devlink: Improve detection of overlapping cycles
> driver core: fw_devlink: Improve logs for cycle detection

For this series:

Tested-by: Xu Yang <[email protected]>

Thanks,
Xu Yang