| Message ID | 1555429864-23291-1-git-send-email-eajames@linux.ibm.com |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | [dev-5.0,v2,1/2] hwmon (occ): Store error condition for rate-limited polls | expand |
On Wed, 17 Apr 2019, at 01:22, Eddie James wrote: > The OCC driver limits the rate of sending poll commands to the OCC. If a > user reads a hwmon entry after a poll response resulted in an error and > is rate-limited, the error is invisible to the user. Fix this by storing > the last error and returning that in the rate-limited case. > > Signed-off-by: Eddie James <eajames@linux.ibm.com> > --- > drivers/hwmon/occ/common.c | 4 ++++ > drivers/hwmon/occ/common.h | 3 ++- > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c > index c888f4a..0e812ef 100644 > --- a/drivers/hwmon/occ/common.c > +++ b/drivers/hwmon/occ/common.c > @@ -138,6 +138,7 @@ static int occ_poll(struct occ *occ) > /* mutex should already be locked if necessary */ > rc = occ->send_cmd(occ, cmd); > if (rc) { > + occ->last_error = rc; > if (occ->error_count++ > OCC_ERROR_COUNT_THRESHOLD) > occ->error = rc; > > @@ -146,6 +147,7 @@ static int occ_poll(struct occ *occ) > > /* clear error since communication was successful */ > occ->error_count = 0; > + occ->last_error = 0; > occ->error = 0; > > /* check for safe state */ > @@ -207,6 +209,8 @@ int occ_update_response(struct occ *occ) > if (time_after(jiffies, occ->last_update + OCC_UPDATE_FREQUENCY)) { > rc = occ_poll(occ); > occ->last_update = jiffies; > + } else { > + rc = occ->last_error; > } > > mutex_unlock(&occ->lock); > diff --git a/drivers/hwmon/occ/common.h b/drivers/hwmon/occ/common.h > index 7c44df3..c676e48 100644 > --- a/drivers/hwmon/occ/common.h > +++ b/drivers/hwmon/occ/common.h > @@ -105,7 +105,8 @@ struct occ { > struct attribute_group group; > const struct attribute_group *groups[2]; > > - int error; /* latest transfer error */ > + int error; /* final transfer error after retry */ > + int last_error; /* latest transfer error */ > unsigned int error_count; /* number of xfr errors observed */ > unsigned long last_safe; /* time OCC entered "safe" state */ > > -- > 2.7.4 > > Applied to dev-5.0. Cheers, Andrew
diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c index c888f4a..0e812ef 100644 --- a/drivers/hwmon/occ/common.c +++ b/drivers/hwmon/occ/common.c @@ -138,6 +138,7 @@ static int occ_poll(struct occ *occ) /* mutex should already be locked if necessary */ rc = occ->send_cmd(occ, cmd); if (rc) { + occ->last_error = rc; if (occ->error_count++ > OCC_ERROR_COUNT_THRESHOLD) occ->error = rc; @@ -146,6 +147,7 @@ static int occ_poll(struct occ *occ) /* clear error since communication was successful */ occ->error_count = 0; + occ->last_error = 0; occ->error = 0; /* check for safe state */ @@ -207,6 +209,8 @@ int occ_update_response(struct occ *occ) if (time_after(jiffies, occ->last_update + OCC_UPDATE_FREQUENCY)) { rc = occ_poll(occ); occ->last_update = jiffies; + } else { + rc = occ->last_error; } mutex_unlock(&occ->lock); diff --git a/drivers/hwmon/occ/common.h b/drivers/hwmon/occ/common.h index 7c44df3..c676e48 100644 --- a/drivers/hwmon/occ/common.h +++ b/drivers/hwmon/occ/common.h @@ -105,7 +105,8 @@ struct occ { struct attribute_group group; const struct attribute_group *groups[2]; - int error; /* latest transfer error */ + int error; /* final transfer error after retry */ + int last_error; /* latest transfer error */ unsigned int error_count; /* number of xfr errors observed */ unsigned long last_safe; /* time OCC entered "safe" state */
The OCC driver limits the rate of sending poll commands to the OCC. If a user reads a hwmon entry after a poll response resulted in an error and is rate-limited, the error is invisible to the user. Fix this by storing the last error and returning that in the rate-limited case. Signed-off-by: Eddie James <eajames@linux.ibm.com> --- drivers/hwmon/occ/common.c | 4 ++++ drivers/hwmon/occ/common.h | 3 ++- 2 files changed, 6 insertions(+), 1 deletion(-)