| Message ID | 20160915153917.3001855-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 09/15/2016 08:38 AM, Arnd Bergmann wrote: > When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized > enabled, we can get a warning for the opp core driver: > > drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate': > drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized] > > This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq: > Add COMPILE_TEST for build coverage"), which makes the driver visible in > some configurations that didn't have it before. > > The warning is a false positive that I got with gcc-6.1.1, but there is > a simple workaround in removing the local variables that we get warnings > for (all three are affected depending on the configuration). This also > makes the code easier to read. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
On 15-09-16, 17:38, Arnd Bergmann wrote: > When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized > enabled, we can get a warning for the opp core driver: > > drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate': > drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized] > > This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq: > Add COMPILE_TEST for build coverage"), which makes the driver visible in > some configurations that didn't have it before. > > The warning is a false positive that I got with gcc-6.1.1, but there is > a simple workaround in removing the local variables that we get warnings > for (all three are affected depending on the configuration). This also > makes the code easier to read. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > drivers/base/power/opp/core.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) > > diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c > index df0c70963d9e..4c7c6da7a989 100644 > --- a/drivers/base/power/opp/core.c > +++ b/drivers/base/power/opp/core.c > @@ -584,7 +584,6 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) > struct clk *clk; > unsigned long freq, old_freq; > unsigned long u_volt, u_volt_min, u_volt_max; > - unsigned long ou_volt, ou_volt_min, ou_volt_max; > int ret; > > if (unlikely(!target_freq)) { > @@ -620,11 +619,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) > } > > old_opp = _find_freq_ceil(opp_table, &old_freq); > - if (!IS_ERR(old_opp)) { > - ou_volt = old_opp->u_volt; > - ou_volt_min = old_opp->u_volt_min; > - ou_volt_max = old_opp->u_volt_max; > - } else { > + if (IS_ERR(old_opp)) { > dev_err(dev, "%s: failed to find current OPP for freq %lu (%ld)\n", > __func__, old_freq, PTR_ERR(old_opp)); > } > @@ -683,7 +678,8 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) > restore_voltage: > /* This shouldn't harm even if the voltages weren't updated earlier */ > if (!IS_ERR(old_opp)) > - _set_opp_voltage(dev, reg, ou_volt, ou_volt_min, ou_volt_max); > + _set_opp_voltage(dev, reg, old_opp->u_volt, > + old_opp->u_volt_min, old_opp->u_volt_max); > > return ret; > } Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index df0c70963d9e..4c7c6da7a989 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -584,7 +584,6 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) struct clk *clk; unsigned long freq, old_freq; unsigned long u_volt, u_volt_min, u_volt_max; - unsigned long ou_volt, ou_volt_min, ou_volt_max; int ret; if (unlikely(!target_freq)) { @@ -620,11 +619,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) } old_opp = _find_freq_ceil(opp_table, &old_freq); - if (!IS_ERR(old_opp)) { - ou_volt = old_opp->u_volt; - ou_volt_min = old_opp->u_volt_min; - ou_volt_max = old_opp->u_volt_max; - } else { + if (IS_ERR(old_opp)) { dev_err(dev, "%s: failed to find current OPP for freq %lu (%ld)\n", __func__, old_freq, PTR_ERR(old_opp)); } @@ -683,7 +678,8 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) restore_voltage: /* This shouldn't harm even if the voltages weren't updated earlier */ if (!IS_ERR(old_opp)) - _set_opp_voltage(dev, reg, ou_volt, ou_volt_min, ou_volt_max); + _set_opp_voltage(dev, reg, old_opp->u_volt, + old_opp->u_volt_min, old_opp->u_volt_max); return ret; }
When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized enabled, we can get a warning for the opp core driver: drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate': drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized] This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq: Add COMPILE_TEST for build coverage"), which makes the driver visible in some configurations that didn't have it before. The warning is a false positive that I got with gcc-6.1.1, but there is a simple workaround in removing the local variables that we get warnings for (all three are affected depending on the configuration). This also makes the code easier to read. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/base/power/opp/core.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)