"Once per day per bard level, a bard can use his song or poetics to produce magical effects on those around him (usually including himself, if desired). While these abilities fall under the category of bardic music and the descriptions discuss singing or playing instruments, they can all be activated by reciting poetry, chanting, singing lyrical songs, singing melodies, whistling, playing an instrument, or playing an instrument in combination with some spoken performance. Each ability requires both a minimum bard level and a minimum number of ranks in the Perform skill to qualify; if a bard does not have the required number of ranks in at least one Perform skill, he does not gain the bardic music ability until he acquires the needed ranks."
The description of Bardic Music states that the bard uses his song or poetics..., or performs in his particular idiom if you will. In order for the bard to sing or whatever s/he must sing/recite poetry/fall on face/whatever all of these are charisma-based skills whose actions must take place. I would say that these actions must be performed; i.e., using perform, which is a charisma-based skill.
If one makes the arguement that a die must be rolled for a skill to be used, I present the following—
A roll of a one is not an automatic failure for a skill check. The DC to tumble through an enemy-occupied square is 25. If the character has a +26 tumble modifier, is there a need for a roll? No, it would be silly because the minimum possible check result would be 27. Is this mentioned in the skill descriptions? No, it is obvious. Are you still using the tumble skill? Yes. Did you roll a die? No.
Bardic Music provides you with the minimum required ranks that the bard needs to be successfull. And with the exception of the Music abilities that have variable effects that occur based on the quality of the check, they don't require a roll because you have already surpassed the performance check when dealing with the Music that does not have variable effects. Does this mean that the bard didn't play his/her instrument? No. the description specifically states that the lute/poem/voice was played/recited/used, which (according to the Perform skill descrtiption) is an Action listed in that skill and (as it specifically applies to Bardic Music) is described in that section—"Action: Varies. Trying to earn money by playing in public requires anywhere from an evening’s work to a full day’s performance. The bard’s special Perform-based abilities are described in that class’s description." So when using Bardic Music you are performing an Action (who's description is listied in the Bard section) that falls under the Perform skill.