Commit-ID: a2cd11f7d58a3a5390ee4cbcd8cff634a4d59173 Gitweb: http://git.kernel.org/tip/a2cd11f7d58a3a5390ee4cbcd8cff634a4d59173 Author: Frederic Weisbecker <fweisbec@xxxxxxxxx> AuthorDate: Tue, 24 Sep 2013 17:18:36 +0200 Committer: Frederic Weisbecker <fweisbec@xxxxxxxxx> CommitDate: Tue, 1 Oct 2013 12:53:28 +0200 x86: Tell about irq stack coverage x86-64 runs irq_exit() under the irq stack. So it can afford to run softirqs in hardirq exit without the need to switch the stacks. The hardirq stack is good enough for that. Now x86-64 runs softirqs in the hardirq stack anyway, so what we mostly skip is some needless per cpu refcounting updates there. x86-32 is not concerned because it only runs the irq handler on the irq stack. Acked-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxxxx> Cc: James Hogan <james.hogan@xxxxxxxxxx> Cc: James E.J. Bottomley <jejb@xxxxxxxxxxxxxxxx> Cc: Helge Deller <deller@xxxxxx> Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ee2fb9d..99eb1cc 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -123,6 +123,7 @@ config X86 select COMPAT_OLD_SIGACTION if IA32_EMULATION select RTC_LIB select HAVE_DEBUG_STACKOVERFLOW + select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 config INSTRUCTION_DECODER def_bool y -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
|