Messages in this thread | | | Subject | Re: [PATCH v3 3/3] perf probe: Show better error message when failed to find variable | From | He Kuang <> | Date | Mon, 11 May 2015 17:43:43 +0800 |
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Hi, Ingo
On 2015/5/11 17:30, Ingo Molnar wrote: > * He Kuang <hekuang@huawei.com> wrote: > >> Indicate to check variable location range in error message when we got >> failed to find the variable. >> >> Before this patch: >> >> $ perf probe --add 'generic_perform_write+118 bytes' >> Failed to find the location of bytes at this address. >> Perhaps, it has been optimized out. >> Error: Failed to add events. >> >> After this patch: >> $ perf probe --add 'generic_perform_write+118 bytes' >> Failed to find the location of bytes at this address. > What does this sentence mean? I thought 'address' means 'location of > bytes'. So the address identifies the location and obviously we know > that. So this message wants to say something else.
'generic_perform_write' is a function name, while 'bytes' is a local variable in this function. Maybe the variable I chose make you confused.
This maybe clear: Failed to find the location of 'bytes' at this address.
>> Perhaps, it has been optimized out. >> Use -V with --range option to show variable location range. > This suggestion is useful. > >> Error: Failed to add events. > Thanks, > > Ingo > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
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