Re: [PATCH v2 1/6] tracing: add __print_flags_u64()

[Ross Zwisler]

On Thu, Dec 01, 2016 at 09:12:54AM -0500, Steven Rostedt wrote:
> On Wed, 30 Nov 2016 16:45:28 -0700
> Ross Zwisler  wrote:
> > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> > index 3fc2042..ed4398f 100644
> > --- a/kernel/trace/trace_output.c
> > +++ b/kernel/trace/trace_output.c
> > @@ -124,6 +124,44 @@ EXPORT_SYMBOL(trace_print_symbols_seq);
> >  
> >  #if BITS_PER_LONG == 32
> >  const char *
> > +trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> > + unsigned long long flags,
> > + const struct trace_print_flags_u64 *flag_array)
> > +{
> > +   unsigned long mask;
> 
> Don't you want mask to be unsigned long long?

Yep, thanks for spotting that.  I'll fix it in v3.

Re: [PATCH v2 1/6] tracing: add __print_flags_u64()

[Ross Zwisler]

On Thu, Dec 01, 2016 at 09:12:54AM -0500, Steven Rostedt wrote:
> On Wed, 30 Nov 2016 16:45:28 -0700
> Ross Zwisler  wrote:
> > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> > index 3fc2042..ed4398f 100644
> > --- a/kernel/trace/trace_output.c
> > +++ b/kernel/trace/trace_output.c
> > @@ -124,6 +124,44 @@ EXPORT_SYMBOL(trace_print_symbols_seq);
> >  
> >  #if BITS_PER_LONG == 32
> >  const char *
> > +trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> > + unsigned long long flags,
> > + const struct trace_print_flags_u64 *flag_array)
> > +{
> > +   unsigned long mask;
> 
> Don't you want mask to be unsigned long long?

Yep, thanks for spotting that.  I'll fix it in v3.

Re: [PATCH v2 1/6] tracing: add __print_flags_u64()

[Steven Rostedt]

On Wed, 30 Nov 2016 16:45:28 -0700
Ross Zwisler  wrote:

> Add __print_flags_u64() and the helper trace_print_flags_seq_u64() in the
> same spirit as __print_symbolic_u64() and trace_print_symbols_seq_u64().
> These functions allow us to print symbols associated with flags that are 64
> bits wide even on 32 bit machines.
> 
> These will be used by the DAX code so that we can print the flags set in a
> pfn_t such as PFN_SG_CHAIN, PFN_SG_LAST, PFN_DEV and PFN_MAP.
> 
> Without this new function I was getting errors like the following when
> compiling for i386:
> 
> ./include/linux/pfn_t.h:13:22: warning: large integer implicitly truncated
> to unsigned type [-Woverflow]
>  #define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
>   ^
> 
> Signed-off-by: Ross Zwisler 
> ---
>  include/linux/trace_events.h |  4 
>  include/trace/trace_events.h | 11 +++
>  kernel/trace/trace_output.c  | 38 ++
>  3 files changed, 53 insertions(+)
> 
> diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
> index be00761..db2c3ba 100644
> --- a/include/linux/trace_events.h
> +++ b/include/linux/trace_events.h
> @@ -23,6 +23,10 @@ const char *trace_print_symbols_seq(struct trace_seq *p, 
> unsigned long val,
>   const struct trace_print_flags 
> *symbol_array);
>  
>  #if BITS_PER_LONG == 32
> +const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> +   unsigned long long flags,
> +   const struct trace_print_flags_u64 *flag_array);
> +
>  const char *trace_print_symbols_seq_u64(struct trace_seq *p,
>   unsigned long long val,
>   const struct trace_print_flags_u64
> diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h
> index 467e12f..c6e9f72 100644
> --- a/include/trace/trace_events.h
> +++ b/include/trace/trace_events.h
> @@ -283,8 +283,16 @@ TRACE_MAKE_SYSTEM_STR();
>   trace_print_symbols_seq(p, value, symbols); \
>   })
>  
> +#undef __print_flags_u64
>  #undef __print_symbolic_u64
>  #if BITS_PER_LONG == 32
> +#define __print_flags_u64(flag, delim, flag_array...)
> \
> + ({  \
> + static const struct trace_print_flags_u64 __flags[] =   \
> + { flag_array, { -1, NULL } };   \
> + trace_print_flags_seq_u64(p, delim, flag, __flags); \
> + })
> +
>  #define __print_symbolic_u64(value, symbol_array...) \
>   ({  \
>   static const struct trace_print_flags_u64 symbols[] =   \
> @@ -292,6 +300,9 @@ TRACE_MAKE_SYSTEM_STR();
>   trace_print_symbols_seq_u64(p, value, symbols); \
>   })
>  #else
> +#define __print_flags_u64(flag, delim, flag_array...)
> \
> + __print_flags(flag, delim, flag_array)
> +
>  #define __print_symbolic_u64(value, symbol_array...) \
>   __print_symbolic(value, symbol_array)
>  #endif
> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> index 3fc2042..ed4398f 100644
> --- a/kernel/trace/trace_output.c
> +++ b/kernel/trace/trace_output.c
> @@ -124,6 +124,44 @@ EXPORT_SYMBOL(trace_print_symbols_seq);
>  
>  #if BITS_PER_LONG == 32
>  const char *
> +trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> +   unsigned long long flags,
> +   const struct trace_print_flags_u64 *flag_array)
> +{
> + unsigned long mask;

Don't you want mask to be unsigned long long?

-- Steve

> + const char *str;
> + const char *ret = trace_seq_buffer_ptr(p);
> + int i, first = 1;
> +
> + for (i = 0;  flag_array[i].name && flags; i++) {
> +
> + mask = flag_array[i].mask;
> + if ((flags & mask) != mask)
> + continue;
> +
> + str = flag_array[i].name;
> + flags &= ~mask;
> + if (!first && delim)
> + trace_seq_puts(p, delim);
> + else
> + first = 0;
> + trace_seq_puts(p, str);
> + }
> +
> + /* check for left over flags */
> + if (flags) {
> + if (!first && delim)
> + trace_seq_puts(p, delim);
> + trace_seq_printf(p, "0x%llx", flags);
> + }
> +
> + trace_seq_putc(p, 0);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(trace_print_flags_seq_u64);
> +
> +const char *
>  trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
>const struct trace_print_flags_u64 *symbol_array)
>  {

Re: [PATCH v2 1/6] tracing: add __print_flags_u64()

[Steven Rostedt]

On Wed, 30 Nov 2016 16:45:28 -0700
Ross Zwisler  wrote:

> Add __print_flags_u64() and the helper trace_print_flags_seq_u64() in the
> same spirit as __print_symbolic_u64() and trace_print_symbols_seq_u64().
> These functions allow us to print symbols associated with flags that are 64
> bits wide even on 32 bit machines.
> 
> These will be used by the DAX code so that we can print the flags set in a
> pfn_t such as PFN_SG_CHAIN, PFN_SG_LAST, PFN_DEV and PFN_MAP.
> 
> Without this new function I was getting errors like the following when
> compiling for i386:
> 
> ./include/linux/pfn_t.h:13:22: warning: large integer implicitly truncated
> to unsigned type [-Woverflow]
>  #define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
>   ^
> 
> Signed-off-by: Ross Zwisler 
> ---
>  include/linux/trace_events.h |  4 
>  include/trace/trace_events.h | 11 +++
>  kernel/trace/trace_output.c  | 38 ++
>  3 files changed, 53 insertions(+)
> 
> diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
> index be00761..db2c3ba 100644
> --- a/include/linux/trace_events.h
> +++ b/include/linux/trace_events.h
> @@ -23,6 +23,10 @@ const char *trace_print_symbols_seq(struct trace_seq *p, 
> unsigned long val,
>   const struct trace_print_flags 
> *symbol_array);
>  
>  #if BITS_PER_LONG == 32
> +const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> +   unsigned long long flags,
> +   const struct trace_print_flags_u64 *flag_array);
> +
>  const char *trace_print_symbols_seq_u64(struct trace_seq *p,
>   unsigned long long val,
>   const struct trace_print_flags_u64
> diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h
> index 467e12f..c6e9f72 100644
> --- a/include/trace/trace_events.h
> +++ b/include/trace/trace_events.h
> @@ -283,8 +283,16 @@ TRACE_MAKE_SYSTEM_STR();
>   trace_print_symbols_seq(p, value, symbols); \
>   })
>  
> +#undef __print_flags_u64
>  #undef __print_symbolic_u64
>  #if BITS_PER_LONG == 32
> +#define __print_flags_u64(flag, delim, flag_array...)
> \
> + ({  \
> + static const struct trace_print_flags_u64 __flags[] =   \
> + { flag_array, { -1, NULL } };   \
> + trace_print_flags_seq_u64(p, delim, flag, __flags); \
> + })
> +
>  #define __print_symbolic_u64(value, symbol_array...) \
>   ({  \
>   static const struct trace_print_flags_u64 symbols[] =   \
> @@ -292,6 +300,9 @@ TRACE_MAKE_SYSTEM_STR();
>   trace_print_symbols_seq_u64(p, value, symbols); \
>   })
>  #else
> +#define __print_flags_u64(flag, delim, flag_array...)
> \
> + __print_flags(flag, delim, flag_array)
> +
>  #define __print_symbolic_u64(value, symbol_array...) \
>   __print_symbolic(value, symbol_array)
>  #endif
> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> index 3fc2042..ed4398f 100644
> --- a/kernel/trace/trace_output.c
> +++ b/kernel/trace/trace_output.c
> @@ -124,6 +124,44 @@ EXPORT_SYMBOL(trace_print_symbols_seq);
>  
>  #if BITS_PER_LONG == 32
>  const char *
> +trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
> +   unsigned long long flags,
> +   const struct trace_print_flags_u64 *flag_array)
> +{
> + unsigned long mask;

Don't you want mask to be unsigned long long?

-- Steve

> + const char *str;
> + const char *ret = trace_seq_buffer_ptr(p);
> + int i, first = 1;
> +
> + for (i = 0;  flag_array[i].name && flags; i++) {
> +
> + mask = flag_array[i].mask;
> + if ((flags & mask) != mask)
> + continue;
> +
> + str = flag_array[i].name;
> + flags &= ~mask;
> + if (!first && delim)
> + trace_seq_puts(p, delim);
> + else
> + first = 0;
> + trace_seq_puts(p, str);
> + }
> +
> + /* check for left over flags */
> + if (flags) {
> + if (!first && delim)
> + trace_seq_puts(p, delim);
> + trace_seq_printf(p, "0x%llx", flags);
> + }
> +
> + trace_seq_putc(p, 0);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(trace_print_flags_seq_u64);
> +
> +const char *
>  trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
>const struct trace_print_flags_u64 *symbol_array)
>  {