On Thu, Apr 12, 2018 at 10:09:51AM -0700, Jae Hyun Yoo wrote: [ ... ] > >>>>>>+static int find_core_index(struct peci_cputemp *priv, int channel) > >>>>>>+{ > >>>>>>+ int core_channel = channel - DEFAULT_CHANNEL_NUMS; > >>>>>>+ int idx, found = 0; > >>>>>>+ > >>>>>>+ for (idx = 0; idx < priv->gen_info->core_max; idx++) { > >>>>>>+ if (priv->core_mask & BIT(idx)) { > >>>>>>+ if (core_channel == found) > >>>>>>+ break; > >>>>>>+ > >>>>>>+ found++; > >>>>>>+ } > >>>>>>+ } > >>>>>>+ > >>>>>>+ return idx; > >>>>> > >>>>>What if nothing is found ? > >>>>> > >>>> > >>>>Core temperature group will be registered only when it detects at > >>>>least one core checked by check_resolved_cores(), so > >>>>find_core_index() can be called only when priv->core_mask has a > >>>>non-zero value. The 'nothing is found' case will not happen. > >>>> > >>>That doesn't guarantee a match. If what you are saying is correct > >>>there should always be > >>>a well defined match of channel -> idx, and the search should be > >>>unnecessary. > >>> > >> > >>There could be some disabled cores in the resolved core mask bit > >>sequence also it should remove indexing gap in channel numbering so it > >>is the reason why this search function is needed. Well defined match of > >>channel -> idx would not be always satisfied. > >> > >Are you saying that each call to the function, with the same parameters, > >can return a different result ? > > > > No, the result will be consistent. After reading the priv->core_mask once in > check_resolved_cores(), the value will not be changed. I'm saying about this > case, for example if core number 2 is unresolved in total 4 cores, then the > idx order will be '0, 1, 3' but channel order will be '5, 6, 7' without > making any indexing gap. > And you yet you claim that this is not well defined ? Or are you concerned about the amount of memory consumed by providing an array for the mapping ? Note that an indexing gap is acceptable and, in many cases, preferred. [ ... ] > >>>>>>+ > >>>>>>+ dev_dbg(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), > >>>>>>priv->name); > >>>>>>+ > >>> > >>>Why does this message display the device name twice ? > >>> > >> > >>For an example, dev_name(hwmon_dev) shows 'hwmon5' and priv->name shows > >>'peci-cputemp0'. > >> > >And dev_dbg() shows another device name. So you'll have something like > > > >peci-cputemp0: hwmon5: sensor 'peci-cputemp0' > > > > Practically it shows like > > peci-cputemp 0-30:00: hwmon10: sensor 'peci_cputemp.cpu0' > > where 0-30:00 is assigned by peci core. > And what message would you see for cpu1 ? -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html