Le mercredi 22 juin 2011 à 11:55 +0100, Russell King - ARM Linux a écrit : > From: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> > > Secondary CPU bringup typically calls calibrate_delay() during its > initialization. However, calibrate_delay() modifies a global variable > (loops_per_jiffy) used for udelay() and __delay(). > > A side effect of 71c696b1 (calibrate: extract fall-back calculation > into own helper) introduced in the 2.6.39 merge window means that we > end up with a substantial period where loops_per_jiffy is zero. This > causes the spinlock debugging code to malfunction: ... > > + loops_per_jiffy = lpj; > printed = true; > } To be 100% safe, I would use ACCESS_ONCE(loops_per_jiffy) = lpj; But I assume no current gcc would be that stupid ;) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
