| Message ID | 20181203092847.76613-1-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1] usb: dwc3: trace: Refactor nested switch to make compiler happy | expand |
Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes: > The missed break statement in the outer switch makes the code fall through > always and thus always same value will be printed. > > Besides that, compiler warns about missed fall through marker: > > drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: > drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] > switch (pcm) { > ^~~~~~ > > Refactor nested switch statements to work correctly without > compilation warnings. > > Fixes: fa8d965d736b ("usb: dwc3: trace: pretty print high-bandwidth transfers too") > Cc: Felipe Balbi <felipe.balbi@linux.intel.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > drivers/usb/dwc3/trace.h | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/usb/dwc3/trace.h b/drivers/usb/dwc3/trace.h > index f22714cce070..8e1625a6c19f 100644 > --- a/drivers/usb/dwc3/trace.h > +++ b/drivers/usb/dwc3/trace.h > @@ -238,7 +238,7 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, > ), > TP_printk("%s: trb %p buf %08x%08x size %s%d ctrl %08x (%c%c%c%c:%c%c:%s)", > __get_str(name), __entry->trb, __entry->bph, __entry->bpl, > - ({char *s; > + ({ char *s = ""; > int pcm = ((__entry->size >> 24) & 3) + 1; > switch (__entry->type) { > case USB_ENDPOINT_XFER_INT: > @@ -254,8 +254,6 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, > s = "3x "; > break; > } easier to add "break" here, no? That would be the minimal fix.
On Wed, Dec 05, 2018 at 11:10:46AM +0200, Felipe Balbi wrote: > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes: > > > The missed break statement in the outer switch makes the code fall through > > always and thus always same value will be printed. > > > > Besides that, compiler warns about missed fall through marker: > > > > drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: > > drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] > > switch (pcm) { > > ^~~~~~ > > > > Refactor nested switch statements to work correctly without > > compilation warnings. > > > > Fixes: fa8d965d736b ("usb: dwc3: trace: pretty print high-bandwidth transfers too") > > Cc: Felipe Balbi <felipe.balbi@linux.intel.com> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > --- > > drivers/usb/dwc3/trace.h | 4 +--- > > 1 file changed, 1 insertion(+), 3 deletions(-) > > > > diff --git a/drivers/usb/dwc3/trace.h b/drivers/usb/dwc3/trace.h > > index f22714cce070..8e1625a6c19f 100644 > > --- a/drivers/usb/dwc3/trace.h > > +++ b/drivers/usb/dwc3/trace.h > > @@ -238,7 +238,7 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, > > ), > > TP_printk("%s: trb %p buf %08x%08x size %s%d ctrl %08x (%c%c%c%c:%c%c:%s)", > > __get_str(name), __entry->trb, __entry->bph, __entry->bpl, > > - ({char *s; > > + ({ char *s = ""; > > int pcm = ((__entry->size >> 24) & 3) + 1; > > switch (__entry->type) { > > case USB_ENDPOINT_XFER_INT: > > @@ -254,8 +254,6 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, > > s = "3x "; > > break; > > } > > easier to add "break" here, no? That would be the minimal fix. No. Then you would need to add same default to the inner switch.
On Wed, Dec 05, 2018 at 11:18:45AM +0200, Andy Shevchenko wrote: > On Wed, Dec 05, 2018 at 11:10:46AM +0200, Felipe Balbi wrote: > > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes: > > > > > The missed break statement in the outer switch makes the code fall through > > > always and thus always same value will be printed. > > > > > > Besides that, compiler warns about missed fall through marker: > > > > > > drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: > > > drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] > > > switch (pcm) { > > > ^~~~~~ > > easier to add "break" here, no? That would be the minimal fix. > > No. Then you would need to add same default to the inner switch. Ah, you meant that pcm would be never outside of the given cases. Yes, that's fine then, consider my patch as a bugreport.
Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes: > On Wed, Dec 05, 2018 at 11:18:45AM +0200, Andy Shevchenko wrote: >> On Wed, Dec 05, 2018 at 11:10:46AM +0200, Felipe Balbi wrote: >> > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes: >> > >> > > The missed break statement in the outer switch makes the code fall through >> > > always and thus always same value will be printed. >> > > >> > > Besides that, compiler warns about missed fall through marker: >> > > >> > > drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: >> > > drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] >> > > switch (pcm) { >> > > ^~~~~~ > >> > easier to add "break" here, no? That would be the minimal fix. >> >> No. Then you would need to add same default to the inner switch. > > Ah, you meant that pcm would be never outside of the given cases. > Yes, that's fine then, consider my patch as a bugreport. updated locally: From ad7b607f82731eec3ed17d9d22764eb6f09609f9 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Date: Mon, 3 Dec 2018 11:28:47 +0200 Subject: [PATCH] usb: dwc3: trace: add missing break statement to make compiler happy MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The missed break statement in the outer switch makes the code fall through always and thus always same value will be printed. Besides that, compiler warns about missed fall through marker: drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] switch (pcm) { ^~~~~~ Add the missing break statement to work correctly without compilation warnings. Fixes: fa8d965d736b ("usb: dwc3: trace: pretty print high-bandwidth transfers too") Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> --- drivers/usb/dwc3/trace.h | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/dwc3/trace.h b/drivers/usb/dwc3/trace.h index 50fb6f2d92dd..36e5a4795fc8 100644 --- a/drivers/usb/dwc3/trace.h +++ b/drivers/usb/dwc3/trace.h @@ -254,6 +254,7 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, s = "3x "; break; } + break; default: s = ""; } s; }),
diff --git a/drivers/usb/dwc3/trace.h b/drivers/usb/dwc3/trace.h index f22714cce070..8e1625a6c19f 100644 --- a/drivers/usb/dwc3/trace.h +++ b/drivers/usb/dwc3/trace.h @@ -238,7 +238,7 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, ), TP_printk("%s: trb %p buf %08x%08x size %s%d ctrl %08x (%c%c%c%c:%c%c:%s)", __get_str(name), __entry->trb, __entry->bph, __entry->bpl, - ({char *s; + ({ char *s = ""; int pcm = ((__entry->size >> 24) & 3) + 1; switch (__entry->type) { case USB_ENDPOINT_XFER_INT: @@ -254,8 +254,6 @@ DECLARE_EVENT_CLASS(dwc3_log_trb, s = "3x "; break; } - default: - s = ""; } s; }), DWC3_TRB_SIZE_LENGTH(__entry->size), __entry->ctrl, __entry->ctrl & DWC3_TRB_CTRL_HWO ? 'H' : 'h',
The missed break statement in the outer switch makes the code fall through always and thus always same value will be printed. Besides that, compiler warns about missed fall through marker: drivers/usb/dwc3/./trace.h: In function ‘trace_raw_output_dwc3_log_trb’: drivers/usb/dwc3/./trace.h:246:4: warning: this statement may fall through [-Wimplicit-fallthrough=] switch (pcm) { ^~~~~~ Refactor nested switch statements to work correctly without compilation warnings. Fixes: fa8d965d736b ("usb: dwc3: trace: pretty print high-bandwidth transfers too") Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> --- drivers/usb/dwc3/trace.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)