The patch titled Subject: nmi watchdog: quiet down the boot messages has been added to the -mm tree. Its filename is nmi-watchdog-quiet-down-the-boot-messages.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Don Zickus <dzickus@xxxxxxxxxx> Subject: nmi watchdog: quiet down the boot messages A bunch of bugzillas have complained how noisy the nmi_watchdog is during boot-up especially with its expected failure cases (like virt and bios resource contention). This is my attempt to quiet them down and keep it less confusing for the end user. What I did is print the message for cpu0 and save it for future comparisons. If future cpus have an identical message as cpu0, then don't print the redundant info. However, if a future cpu has a different message, happily print that loudly. Before the change, you would see something like: ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver. ... version: 2 ... bit width: 40 ... generic registers: 2 ... value mask: 000000ffffffffff ... max period: 000000007fffffff ... fixed-purpose events: 3 ... event mask: 0000000700000003 NMI watchdog enabled, takes one hw-pmu counter. Booting Node 0, Processors #1 NMI watchdog enabled, takes one hw-pmu counter. #2 NMI watchdog enabled, takes one hw-pmu counter. #3 Ok. NMI watchdog enabled, takes one hw-pmu counter. Brought up 4 CPUs Total of 4 processors activated (22607.24 BogoMIPS). After the change, it is simplified to: ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver. ... version: 2 ... bit width: 40 ... generic registers: 2 ... value mask: 000000ffffffffff ... max period: 000000007fffffff ... fixed-purpose events: 3 ... event mask: 0000000700000003 NMI watchdog enabled, takes one hw-pmu counter. Booting Node 0, Processors #1 #2 #3 Ok. Brought up 4 CPUs Signed-off-by: Don Zickus <dzickus@xxxxxxxxxx> Reported-by: Nathan Zimmer <nzimmer@xxxxxxx> Tested-by: Nathan Zimmer <nzimmer@xxxxxxx> Cc: Joe Perches <joe@xxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/watchdog.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff -puN kernel/watchdog.c~nmi-watchdog-quiet-down-the-boot-messages kernel/watchdog.c --- a/kernel/watchdog.c~nmi-watchdog-quiet-down-the-boot-messages +++ a/kernel/watchdog.c @@ -377,6 +377,13 @@ static int watchdog_nmi_enable(int cpu) struct perf_event_attr *wd_attr; struct perf_event *event = per_cpu(watchdog_ev, cpu); + /* + * People like the simple clean cpu node info on boot. + * Reduce the watchdog noise by only printing messages + * that are different from what cpu0 displayed. + */ + static unsigned long cpu0_err; + /* is it already setup and enabled? */ if (event && event->state > PERF_EVENT_STATE_OFF) goto out; @@ -390,11 +397,21 @@ static int watchdog_nmi_enable(int cpu) /* Try to register using hardware perf events */ event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL); + + /* save cpu0 error for future comparision */ + if (cpu == 0 && IS_ERR(event)) + cpu0_err = PTR_ERR(event); + if (!IS_ERR(event)) { - pr_info("enabled, takes one hw-pmu counter.\n"); + /* only print for cpu0 or different than cpu0 */ + if (cpu ==0 || cpu0_err) + pr_info("enabled, takes one hw-pmu counter.\n"); goto out_save; } + /* skip displaying the same error again */ + if (cpu > 0 && (PTR_ERR(event) == cpu0_err)) + return PTR_ERR(event); /* vary the KERN level based on the returned errno */ if (PTR_ERR(event) == -EOPNOTSUPP) _ Subject: Subject: nmi watchdog: quiet down the boot messages Patches currently in -mm which might be from dzickus@xxxxxxxxxx are origin.patch linux-next.patch nmi-watchdog-quiet-down-the-boot-messages.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume-fix.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume-fix-fix-fix.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume-fix-fix.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume-v2.patch nmi-watchdog-fix-for-lockup-detector-breakage-on-resume-v2-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html