2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Shai Fultheim <shai@xxxxxxxxxxx> commit 42fa4250436304d4650fa271f37671f6cee24e08 upstream. On virtual environments, apic_read could take a long time. As a result, under certain conditions the ack pending loop may exit without any queued irqs left, but after more than one second. A warning will be printed needlessly in this case. If the loop is about to exit regardless of max_loops, don't update it. Signed-off-by: Shai Fultheim <shai@xxxxxxxxxxx> [ rebased and reworded the commit message] Signed-off-by: Ido Yariv <ido@xxxxxxxxxx> Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1334873552-31346-1-git-send-email-ido@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> (cherry picked from commit c9f1417be9acae3a9867f8bdab2b7924d76cf6ac) Signed-off-by: Willy Tarreau <w@xxxxxx> --- arch/x86/kernel/apic/apic.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 1d2d670..be4bf4c 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1250,11 +1250,13 @@ void __cpuinit setup_local_APIC(void) acked); break; } - if (cpu_has_tsc) { - rdtscll(ntsc); - max_loops = (cpu_khz << 10) - (ntsc - tsc); - } else - max_loops--; + if (queued) { + if (cpu_has_tsc) { + rdtscll(ntsc); + max_loops = (cpu_khz << 10) - (ntsc - tsc); + } else + max_loops--; + } } while (queued && max_loops > 0); WARN_ON(max_loops <= 0); -- 1.7.12.2.21.g234cd45.dirty -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html