kernel.git/arch/x86/kernel/tsc.c, branch linux-6.10.y

Merge tag 'x86-cpu-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2024-05-14T01:44:44Z

Pull x86 cpu updates from Ingo Molnar: - Rework the x86 CPU vendor/family/model code: introduce the 'VFM' value that is an 8+8+8 bit concatenation of the vendor/family/model value, and add macros that work on VFM values. This simplifies the addition of new Intel models & families, and simplifies existing enumeration & quirk code. - Add support for the AMD 0x80000026 leaf, to better parse topology information - Optimize the NUMA allocation layout of more per-CPU data structures - Improve the workaround for AMD erratum 1386 - Clear TME from /proc/cpuinfo as well, when disabled by the firmware - Improve x86 self-tests - Extend the mce_record tracepoint with the ::ppin and ::microcode fields - Implement recovery for MCE errors in TDX/SEAM non-root mode - Misc cleanups and fixes * tag 'x86-cpu-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) x86/mm: Switch to new Intel CPU model defines x86/tsc_msr: Switch to new Intel CPU model defines x86/tsc: Switch to new Intel CPU model defines x86/cpu: Switch to new Intel CPU model defines x86/resctrl: Switch to new Intel CPU model defines x86/microcode/intel: Switch to new Intel CPU model defines x86/mce: Switch to new Intel CPU model defines x86/cpu: Switch to new Intel CPU model defines x86/cpu/intel_epb: Switch to new Intel CPU model defines x86/aperfmperf: Switch to new Intel CPU model defines x86/apic: Switch to new Intel CPU model defines perf/x86/msr: Switch to new Intel CPU model defines perf/x86/intel/uncore: Switch to new Intel CPU model defines perf/x86/intel/pt: Switch to new Intel CPU model defines perf/x86/lbr: Switch to new Intel CPU model defines perf/x86/intel/cstate: Switch to new Intel CPU model defines x86/bugs: Switch to new Intel CPU model defines x86/bugs: Switch to new Intel CPU model defines x86/cpu/vfm: Update arch/x86/include/asm/intel-family.h x86/cpu/vfm: Add new macros to work with (vendor/family/model) values ...

x86/tsc: Switch to new Intel CPU model defines

2024-04-29T08:31:32Z

New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck Signed-off-by: Dave Hansen Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/all/20240424181517.41907-1-tony.luck%40intel.com

x86/tsc: Make __use_tsc __ro_after_init

2024-03-22T10:18:20Z

__use_tsc is only ever enabled in __init tsc_enable_sched_clock(), so mark it as __ro_after_init. Signed-off-by: Valentin Schneider Signed-off-by: Ingo Molnar Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20240313180106.2917308-5-vschneid@redhat.com

treewide: Remove system_counterval_t.cs, which is never read

2024-02-07T16:05:21Z

The clocksource pointer in struct system_counterval_t is not evaluated any more. Remove the code setting the member, and the member itself. Signed-off-by: Peter Hilber Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240201010453.2212371-8-peter.hilber@opensynergy.com

x86/tsc: Add clocksource ID, set system_counterval_t.cs_id

2024-02-07T16:05:21Z

Add a clocksource ID for TSC and a distinct one for the early TSC. Use distinct IDs for TSC and early TSC, since those also have distinct clocksource structs. This should help to keep existing semantics when comparing clocksources. Also, set the recently added struct system_counterval_t member cs_id to the TSC ID in the cases where the clocksource member is being set to the TSC clocksource. In the future, get_device_system_crosststamp() will compare the clocksource ID in struct system_counterval_t, rather than the clocksource. For the x86 ART related code, system_counterval_t.cs == NULL corresponds to system_counterval_t.cs_id == CSID_GENERIC (0). Signed-off-by: Peter Hilber Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240201010453.2212371-4-peter.hilber@opensynergy.com

x86/tsc: Correct kernel-doc notation

2024-02-07T16:05:21Z

Add or modify function descriptions to remove kernel-doc warnings: tsc.c:655: warning: missing initial short description on line: * native_calibrate_tsc tsc.c:1339: warning: Excess function parameter 'cycles' description in 'convert_art_ns_to_tsc' tsc.c:1339: warning: Excess function parameter 'cs' description in 'convert_art_ns_to_tsc' tsc.c:1373: warning: Function parameter or member 'work' not described in 'tsc_refine_calibration_work' Signed-off-by: Randy Dunlap Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20231221033620.32379-1-rdunlap@infradead.org

x86/tsc: Extend watchdog check exemption to 4-Sockets platform

2023-07-14T22:17:09Z

There were reports again that the tsc clocksource on 4 sockets x86 servers was wrongly judged as 'unstable' by 'jiffies' and other watchdogs, and disabled [1][2]. Commit b50db7095fe0 ("x86/tsc: Disable clocksource watchdog for TSC on qualified platorms") was introduce to deal with these false alarms of tsc unstable issues, covering qualified platforms for 2 sockets or smaller ones. And from history of chasing TSC issues, Thomas and Peter only saw real TSC synchronization issue on 8 socket machines. So extend the exemption to 4 sockets to fix the issue. Rui also proposed another way to disable 'jiffies' as clocksource watchdog [3], which can also solve problem in [1]. in an architecture independent way, but can't cure the problem in [2]. whose watchdog is HPET or PMTIMER, while 'jiffies' is mostly used as watchdog in boot phase. 'nr_online_nodes' has known inaccurate problem for cases like platform with cpu-less memory nodes, sub numa cluster enabled, fakenuma, kernel cmdline parameter 'maxcpus=', etc. The harmful case is the 'maxcpus' one which could possibly under estimates the package number, and disable the watchdog, but bright side is it is mostly for debug usage. All these will be addressed in other patches, as discussed in thread [4]. [1]. https://lore.kernel.org/all/9d3bf570-3108-0336-9c52-9bee15767d29@huawei.com/ [2]. https://lore.kernel.org/lkml/06df410c-2177-4671-832f-339cff05b1d9@paulmck-laptop/ [3]. https://lore.kernel.org/all/bd5b97f89ab2887543fc262348d1c7cafcaae536.camel@intel.com/ [4]. https://lore.kernel.org/all/20221021062131.1826810-1-feng.tang@intel.com/ Reported-by: Yu Liao Reported-by: Paul E. McKenney Signed-off-by: Feng Tang Signed-off-by: Paul E. McKenney

Merge tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-06-27T21:03:21Z

Pull scheduler updates from Ingo Molnar: "Scheduler SMP load-balancer improvements: - Avoid unnecessary migrations within SMT domains on hybrid systems. Problem: On hybrid CPU systems, (processors with a mixture of higher-frequency SMT cores and lower-frequency non-SMT cores), under the old code lower-priority CPUs pulled tasks from the higher-priority cores if more than one SMT sibling was busy - resulting in many unnecessary task migrations. Solution: The new code improves the load balancer to recognize SMT cores with more than one busy sibling and allows lower-priority CPUs to pull tasks, which avoids superfluous migrations and lets lower-priority cores inspect all SMT siblings for the busiest queue. - Implement the 'runnable boosting' feature in the EAS balancer: consider CPU contention in frequency, EAS max util & load-balance busiest CPU selection. This improves CPU utilization for certain workloads, while leaves other key workloads unchanged. Scheduler infrastructure improvements: - Rewrite the scheduler topology setup code by consolidating it into the build_sched_topology() helper function and building it dynamically on the fly. - Resolve the local_clock() vs. noinstr complications by rewriting the code: provide separate sched_clock_noinstr() and local_clock_noinstr() functions to be used in instrumentation code, and make sure it is all instrumentation-safe. Fixes: - Fix a kthread_park() race with wait_woken() - Fix misc wait_task_inactive() bugs unearthed by the -rt merge: - Fix UP PREEMPT bug by unifying the SMP and UP implementations - Fix task_struct::saved_state handling - Fix various rq clock update bugs, unearthed by turning on the rq clock debugging code. - Fix the PSI WINDOW_MIN_US trigger limit, which was easy to trigger by creating enough cgroups, by removing the warnign and restricting window size triggers to PSI file write-permission or CAP_SYS_RESOURCE. - Propagate SMT flags in the topology when removing degenerate domain - Fix grub_reclaim() calculation bug in the deadline scheduler code - Avoid resetting the min update period when it is unnecessary, in psi_trigger_destroy(). - Don't balance a task to its current running CPU in load_balance(), which was possible on certain NUMA topologies with overlapping groups. - Fix the sched-debug printing of rq->nr_uninterruptible Cleanups: - Address various -Wmissing-prototype warnings, as a preparation to (maybe) enable this warning in the future. - Remove unused code - Mark more functions __init - Fix shadow-variable warnings" * tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) sched/core: Avoid multiple calling update_rq_clock() in __cfsb_csd_unthrottle() sched/core: Avoid double calling update_rq_clock() in __balance_push_cpu_stop() sched/core: Fixed missing rq clock update before calling set_rq_offline() sched/deadline: Update GRUB description in the documentation sched/deadline: Fix bandwidth reclaim equation in GRUB sched/wait: Fix a kthread_park race with wait_woken() sched/topology: Mark set_sched_topology() __init sched/fair: Rename variable cpu_util eff_util arm64/arch_timer: Fix MMIO byteswap sched/fair, cpufreq: Introduce 'runnable boosting' sched/fair: Refactor CPU utilization functions cpuidle: Use local_clock_noinstr() sched/clock: Provide local_clock_noinstr() x86/tsc: Provide sched_clock_noinstr() clocksource: hyper-v: Provide noinstr sched_clock() clocksource: hyper-v: Adjust hv_read_tsc_page_tsc() to avoid special casing U64_MAX x86/vdso: Fix gettimeofday masking math64: Always inline u128 version of mul_u64_u64_shr() s390/time: Provide sched_clock_noinstr() loongarch: Provide noinstr sched_clock_read() ...

x86/tsc: Provide sched_clock_noinstr()

2023-06-05T19:11:08Z

With the intent to provide local_clock_noinstr(), a variant of local_clock() that's safe to be called from noinstr code (with the assumption that any such code will already be non-preemptible), prepare for things by providing a noinstr sched_clock_noinstr() function. Specifically, preempt_enable_*() calls out to schedule(), which upsets noinstr validation efforts. vmlinux.o: warning: objtool: native_sched_clock+0x96: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section vmlinux.o: warning: objtool: kvm_clock_read+0x22: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) Tested-by: Michael Kelley # Hyper-V Link: https://lore.kernel.org/r/20230519102715.910937674@infradead.org

x86/smpboot: Avoid pointless delay calibration if TSC is synchronized

2023-05-15T11:44:48Z

When TSC is synchronized across sockets then there is no reason to calibrate the delay for the first CPU which comes up on a socket. Just reuse the existing calibration value. This removes 100ms pointlessly wasted time from CPU hotplug per socket. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Tested-by: Michael Kelley Tested-by: Oleksandr Natalenko Tested-by: Helge Deller # parisc Tested-by: Guilherme G. Piccoli # Steam Deck Link: https://lore.kernel.org/r/20230512205255.608773568@linutronix.de