| Message ID | 20200916133456.79280-1-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [v1,1/3] dmaengine: dmatest: Fix regression when run command on misconfigured channel | expand |
HI Andy/Vladimir On 16-09-20, 16:34, Andy Shevchenko wrote: > From: Vladimir Murzin <vladimir.murzin@arm.com> Subject of the patch is not apt. It describes the effect of this patch, which is to fix the regression but does not describe the change. Please revise it to describe the change done in this patch > Andy reported that commit 6b41030fdc79 ("dmaengine: dmatest: > Restore default for channel") broke his scripts for the case > where "busy" channel is used for configuration with expectation > that run command would do nothing (and return 0). Instead, > behavior was (unintentionally) changed to treat such case as > under-configuration and progress with defaults, i.e. run command > would start a test with default setting for channel (which would > use all channels). but a mis-configured channel returning success and doing nothing does not look as a good behaviour, I agree it broke Andy's script but the behaviour was not good to start with ;) > Restore original behavior with tracking status of channel setter > so we can distinguish between misconfigured and under-configured > cases in run command and act accordingly. > > Fixes: 6b41030fdc79 ("dmaengine: dmatest: Restore default for channel") > Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > drivers/dma/dmatest.c | 28 ++++++++++++++++++++++------ > 1 file changed, 22 insertions(+), 6 deletions(-) > > diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c > index b2790641370a..4c9a9d7b48bb 100644 > --- a/drivers/dma/dmatest.c > +++ b/drivers/dma/dmatest.c > @@ -129,6 +129,7 @@ struct dmatest_params { > * @nr_channels: number of channels under test > * @lock: access protection to the fields of this structure > * @did_init: module has been initialized completely > + * @last_error: test has faced configuration issues > */ > static struct dmatest_info { > /* Test parameters */ > @@ -137,6 +138,7 @@ static struct dmatest_info { > /* Internal state */ > struct list_head channels; > unsigned int nr_channels; > + int last_error; > struct mutex lock; > bool did_init; > } test_info = { > @@ -1202,10 +1204,22 @@ static int dmatest_run_set(const char *val, const struct kernel_param *kp) > return ret; > } else if (dmatest_run) { > if (!is_threaded_test_pending(info)) { > - pr_info("No channels configured, continue with any\n"); > - if (!is_threaded_test_run(info)) > - stop_threaded_test(info); > - add_threaded_test(info); > + /* > + * We have nothing to run. This can be due to: > + */ > + ret = info->last_error; > + if (ret) { > + /* 1) Mis-configuration */ > + pr_warn("Channel misconfigured, can't continue\n"); I would think this should be error > + mutex_unlock(&info->lock); > + return ret; > + } else { > + /* 2) We rely on defaults */ > + pr_info("No channels configured, continue with any\n"); > + if (!is_threaded_test_run(info)) > + stop_threaded_test(info); > + add_threaded_test(info); > + } > } > start_threaded_tests(info); > } else { > @@ -1222,7 +1236,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > struct dmatest_info *info = &test_info; > struct dmatest_chan *dtc; > char chan_reset_val[20]; > - int ret = 0; > + int ret; Does this belong to this fix? > > mutex_lock(&info->lock); > ret = param_set_copystring(val, kp); > @@ -1230,7 +1244,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > mutex_unlock(&info->lock); > return ret; > } > - /*Clear any previously run threads */ > + /* Clear any previously run threads */ Lets keep style issues away from fixes please > if (!is_threaded_test_run(info) && !is_threaded_test_pending(info)) > stop_threaded_test(info); > /* Reject channels that are already registered */ > @@ -1277,12 +1291,14 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > goto add_chan_err; > } > > + info->last_error = ret; > mutex_unlock(&info->lock); > > return ret; > > add_chan_err: > param_set_copystring(chan_reset_val, kp); > + info->last_error = ret; > mutex_unlock(&info->lock); > > return ret; > -- > 2.28.0
On Thu, Sep 17, 2020 at 04:00:34PM +0530, Vinod Koul wrote: Thanks for review, my answers below. > On 16-09-20, 16:34, Andy Shevchenko wrote: > > From: Vladimir Murzin <vladimir.murzin@arm.com> > > Subject of the patch is not apt. It describes the effect of this patch, > which is to fix the regression but does not describe the change. Please > revise it to describe the change done in this patch OK! > > Andy reported that commit 6b41030fdc79 ("dmaengine: dmatest: > > Restore default for channel") broke his scripts for the case > > where "busy" channel is used for configuration with expectation > > that run command would do nothing (and return 0). Instead, > > behavior was (unintentionally) changed to treat such case as > > under-configuration and progress with defaults, i.e. run command > > would start a test with default setting for channel (which would > > use all channels). > > but a mis-configured channel returning success and doing nothing does > not look as a good behaviour, I agree it broke Andy's script but the > behaviour was not good to start with ;) Which used to be a previous behaviour. I don't understand what should I do here as after this patch (and even after the initial multi-channel support patch) the behaviour is like you desire. > > Restore original behavior with tracking status of channel setter > > so we can distinguish between misconfigured and under-configured > > cases in run command and act accordingly. > > > > Fixes: 6b41030fdc79 ("dmaengine: dmatest: Restore default for channel") > > Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > --- > > drivers/dma/dmatest.c | 28 ++++++++++++++++++++++------ > > 1 file changed, 22 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c > > index b2790641370a..4c9a9d7b48bb 100644 > > --- a/drivers/dma/dmatest.c > > +++ b/drivers/dma/dmatest.c > > @@ -129,6 +129,7 @@ struct dmatest_params { > > * @nr_channels: number of channels under test > > * @lock: access protection to the fields of this structure > > * @did_init: module has been initialized completely > > + * @last_error: test has faced configuration issues > > */ > > static struct dmatest_info { > > /* Test parameters */ > > @@ -137,6 +138,7 @@ static struct dmatest_info { > > /* Internal state */ > > struct list_head channels; > > unsigned int nr_channels; > > + int last_error; > > struct mutex lock; > > bool did_init; > > } test_info = { > > @@ -1202,10 +1204,22 @@ static int dmatest_run_set(const char *val, const struct kernel_param *kp) > > return ret; > > } else if (dmatest_run) { > > if (!is_threaded_test_pending(info)) { > > - pr_info("No channels configured, continue with any\n"); > > - if (!is_threaded_test_run(info)) > > - stop_threaded_test(info); > > - add_threaded_test(info); > > + /* > > + * We have nothing to run. This can be due to: > > + */ > > + ret = info->last_error; > > + if (ret) { > > + /* 1) Mis-configuration */ > > + pr_warn("Channel misconfigured, can't continue\n"); > > I would think this should be error OK! > > + mutex_unlock(&info->lock); > > + return ret; > > + } else { > > + /* 2) We rely on defaults */ > > + pr_info("No channels configured, continue with any\n"); > > + if (!is_threaded_test_run(info)) > > + stop_threaded_test(info); > > + add_threaded_test(info); > > + } > > } > > start_threaded_tests(info); > > } else { > > @@ -1222,7 +1236,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > > struct dmatest_info *info = &test_info; > > struct dmatest_chan *dtc; > > char chan_reset_val[20]; > > - int ret = 0; > > + int ret; > > Does this belong to this fix? Relatively. It goes under category that we can clean this up because it has relation to what we need below. I will leave it in v2 as it is in v1. > > mutex_lock(&info->lock); > > ret = param_set_copystring(val, kp); > > @@ -1230,7 +1244,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > > mutex_unlock(&info->lock); > > return ret; > > } > > - /*Clear any previously run threads */ > > + /* Clear any previously run threads */ > > Lets keep style issues away from fixes please OK! > > if (!is_threaded_test_run(info) && !is_threaded_test_pending(info)) > > stop_threaded_test(info); > > /* Reject channels that are already registered */ > > @@ -1277,12 +1291,14 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) > > goto add_chan_err; > > } > > > > + info->last_error = ret; > > mutex_unlock(&info->lock); > > > > return ret; > > > > add_chan_err: > > param_set_copystring(chan_reset_val, kp); > > + info->last_error = ret; > > mutex_unlock(&info->lock); > > > > return ret; > > -- > > 2.28.0 > > -- > ~Vinod
On Tue, Sep 22, 2020 at 02:47:22PM +0300, Andy Shevchenko wrote: > On Thu, Sep 17, 2020 at 04:00:34PM +0530, Vinod Koul wrote: > > On 16-09-20, 16:34, Andy Shevchenko wrote: > > > From: Vladimir Murzin <vladimir.murzin@arm.com> > > > Andy reported that commit 6b41030fdc79 ("dmaengine: dmatest: > > > Restore default for channel") broke his scripts for the case > > > where "busy" channel is used for configuration with expectation > > > that run command would do nothing (and return 0). Instead, > > > behavior was (unintentionally) changed to treat such case as > > > under-configuration and progress with defaults, i.e. run command > > > would start a test with default setting for channel (which would > > > use all channels). > > > > but a mis-configured channel returning success and doing nothing does > > not look as a good behaviour, I agree it broke Andy's script but the > > behaviour was not good to start with ;) > > Which used to be a previous behaviour. I don't understand what should I do here > as after this patch (and even after the initial multi-channel support patch) > the behaviour is like you desire. Okay, I have dropped the part '(and return 0)' to avoid ambiguity. > > > Restore original behavior with tracking status of channel setter > > > so we can distinguish between misconfigured and under-configured > > > cases in run command and act accordingly.
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index b2790641370a..4c9a9d7b48bb 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -129,6 +129,7 @@ struct dmatest_params { * @nr_channels: number of channels under test * @lock: access protection to the fields of this structure * @did_init: module has been initialized completely + * @last_error: test has faced configuration issues */ static struct dmatest_info { /* Test parameters */ @@ -137,6 +138,7 @@ static struct dmatest_info { /* Internal state */ struct list_head channels; unsigned int nr_channels; + int last_error; struct mutex lock; bool did_init; } test_info = { @@ -1202,10 +1204,22 @@ static int dmatest_run_set(const char *val, const struct kernel_param *kp) return ret; } else if (dmatest_run) { if (!is_threaded_test_pending(info)) { - pr_info("No channels configured, continue with any\n"); - if (!is_threaded_test_run(info)) - stop_threaded_test(info); - add_threaded_test(info); + /* + * We have nothing to run. This can be due to: + */ + ret = info->last_error; + if (ret) { + /* 1) Mis-configuration */ + pr_warn("Channel misconfigured, can't continue\n"); + mutex_unlock(&info->lock); + return ret; + } else { + /* 2) We rely on defaults */ + pr_info("No channels configured, continue with any\n"); + if (!is_threaded_test_run(info)) + stop_threaded_test(info); + add_threaded_test(info); + } } start_threaded_tests(info); } else { @@ -1222,7 +1236,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) struct dmatest_info *info = &test_info; struct dmatest_chan *dtc; char chan_reset_val[20]; - int ret = 0; + int ret; mutex_lock(&info->lock); ret = param_set_copystring(val, kp); @@ -1230,7 +1244,7 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) mutex_unlock(&info->lock); return ret; } - /*Clear any previously run threads */ + /* Clear any previously run threads */ if (!is_threaded_test_run(info) && !is_threaded_test_pending(info)) stop_threaded_test(info); /* Reject channels that are already registered */ @@ -1277,12 +1291,14 @@ static int dmatest_chan_set(const char *val, const struct kernel_param *kp) goto add_chan_err; } + info->last_error = ret; mutex_unlock(&info->lock); return ret; add_chan_err: param_set_copystring(chan_reset_val, kp); + info->last_error = ret; mutex_unlock(&info->lock); return ret;