Thank you for clarifying.
On Mon, Oct 26, 2015 at 4:18 PM, Russell King - ARM Linux <li...@arm.linux.org.uk> wrote: > On Mon, Oct 26, 2015 at 12:19:31PM +0530, raghu MG wrote: >> Hello, >> I have couple of questions. >> 1) In case of UP how is jiffies(timer) get updated while holding spin >> lock using spinlock_irq_save? > > It isn't, and... >> >> 2)My understanding is in smp environment jiffies updation cannot be >> done on processor holding spinlock irrespective of spinlock API.So >> timer interrupt should be enabled across all cores in SoC. Imagine a >> scenario in quad core processor where 4 cores are holding 4 different >> spinlocks & how is the timer interrupt for jiffies handled? > > You can't rely on jiffies being updated while holding a spinlock. > Expecting jiffies to update while holding a spinlock is a bug. > > -- > FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up > according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
