On 3/29/20 6:14 PM, Matthew Wilcox wrote:
> On Fri, Mar 20, 2020 at 02:58:23PM +0900, Jaewon Kim wrote:
>> + TP_printk("addr=%lx err=%ld total_vm=0x%lx flags=0x%lx len=0x%lx lo=0x%lx hi=0x%lx mask=0x%lx ofs=0x%lx\n",
>> + IS_ERR_VALUE(__entry->addr) ? 0 : __entry->addr,
>> + IS_ERR_VALUE(__entry->addr) ? __entry->addr : 0,
>
> I didn't see the IS_ERR_VALUE problem that Vlastimil mentioned get resolved?
Steven is fixing it in trace-cmd:
https://lore.kernel.org/r/20200324200956.821799393@xxxxxxxxxxx
> I might suggest ...
>
> +++ b/include/linux/err.h
> @@ -19,7 +19,8 @@
>
> #ifndef __ASSEMBLY__
>
> -#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
> +#define __IS_ERR_VALUE(x) ((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
> +#define IS_ERR_VALUE(x) unlikely(__IS_ERR_VALUE(x))
So this shouldn't be needed, as we are adding a new tracepoint, not "breaking"
an existing one?
> static inline void * __must_check ERR_PTR(long error)
> {
>
> and then you can use __IS_ERR_VALUE() which removes the unlikely() problem.
>
