diff options
| author | Frederic Weisbecker <[email protected]> | 2013-09-24 17:18:36 +0200 |
|---|---|---|
| committer | Frederic Weisbecker <[email protected]> | 2013-10-01 12:53:28 +0200 |
| commit | a2cd11f7d58a3a5390ee4cbcd8cff634a4d59173 (patch) | |
| tree | 52c80e413e4ec7d048714c372af5d2f49630155c | |
| parent | cc1f027454929924471bea2f362431072e3c71be (diff) | |
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 <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: James Hogan <[email protected]>
Cc: James E.J. Bottomley <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Andrew Morton <[email protected]>
| -rw-r--r-- | arch/x86/Kconfig | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ee2fb9d37745..99eb1cc30dac 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 |