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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-17 13:34:25 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-17 13:34:25 -0800 |
commit | 8a5be36b9303ae167468d4f5e1b3c090b9981396 (patch) | |
tree | ddf1721677782484bab6369a87f13611eafb879a /arch/powerpc/kernel/time.c | |
parent | 09c0796adf0c793462fda1d7c8c43324551405c7 (diff) | |
parent | c1bea0a840ac75dca19bc6aa05575a33eb9fd058 (diff) | |
download | linux-8a5be36b9303ae167468d4f5e1b3c090b9981396.tar.gz linux-8a5be36b9303ae167468d4f5e1b3c090b9981396.tar.bz2 linux-8a5be36b9303ae167468d4f5e1b3c090b9981396.zip |
Merge tag 'powerpc-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Switch to the generic C VDSO, as well as some cleanups of our VDSO
setup/handling code.
- Support for KUAP (Kernel User Access Prevention) on systems using the
hashed page table MMU, using memory protection keys.
- Better handling of PowerVM SMT8 systems where all threads of a core
do not share an L2, allowing the scheduler to make better scheduling
decisions.
- Further improvements to our machine check handling.
- Show registers when unwinding interrupt frames during stack traces.
- Improvements to our pseries (PowerVM) partition migration code.
- Several series from Christophe refactoring and cleaning up various
parts of the 32-bit code.
- Other smaller features, fixes & cleanups.
Thanks to: Alan Modra, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
Kumar K.V, Ard Biesheuvel, Athira Rajeev, Balamuruhan S, Bill Wendling,
Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King,
Daniel Axtens, David Hildenbrand, Frederic Barrat, Ganesh Goudar,
Gautham R. Shenoy, Geert Uytterhoeven, Giuseppe Sacco, Greg Kurz,
Harish, Jan Kratochvil, Jordan Niethe, Kaixu Xia, Laurent Dufour,
Leonardo Bras, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu
Desnoyers, Nathan Lynch, Nicholas Piggin, Oleg Nesterov, Oliver
O'Halloran, Oscar Salvador, Po-Hsu Lin, Qian Cai, Qinglang Miao, Randy
Dunlap, Ravi Bangoria, Sachin Sant, Sandipan Das, Sebastian Andrzej
Siewior , Segher Boessenkool, Srikar Dronamraju, Tyrel Datwyler, Uwe
Kleine-König, Vincent Stehlé, Youling Tang, and Zhang Xiaoxu.
* tag 'powerpc-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (304 commits)
powerpc/32s: Fix cleanup_cpu_mmu_context() compile bug
powerpc: Add config fragment for disabling -Werror
powerpc/configs: Add ppc64le_allnoconfig target
powerpc/powernv: Rate limit opal-elog read failure message
powerpc/pseries/memhotplug: Quieten some DLPAR operations
powerpc/ps3: use dma_mapping_error()
powerpc: force inlining of csum_partial() to avoid multiple csum_partial() with GCC10
powerpc/perf: Fix Threshold Event Counter Multiplier width for P10
powerpc/mm: Fix hugetlb_free_pmd_range() and hugetlb_free_pud_range()
KVM: PPC: Book3S HV: Fix mask size for emulated msgsndp
KVM: PPC: fix comparison to bool warning
KVM: PPC: Book3S: Assign boolean values to a bool variable
powerpc: Inline setup_kup()
powerpc/64s: Mark the kuap/kuep functions non __init
KVM: PPC: Book3S HV: XIVE: Add a comment regarding VP numbering
powerpc/xive: Improve error reporting of OPAL calls
powerpc/xive: Simplify xive_do_source_eoi()
powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_EOI_FW
powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_MASK_FW
powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_SHIFT_BUG
...
Diffstat (limited to 'arch/powerpc/kernel/time.c')
-rw-r--r-- | arch/powerpc/kernel/time.c | 100 |
1 files changed, 4 insertions, 96 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index cf3f8db7e0e3..67feb3524460 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -82,6 +82,7 @@ static struct clocksource clocksource_timebase = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, .mask = CLOCKSOURCE_MASK(64), .read = timebase_read, + .vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER, }; #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF @@ -576,14 +577,11 @@ void timer_interrupt(struct pt_regs *regs) struct pt_regs *old_regs; u64 now; - /* Some implementations of hotplug will get timer interrupts while - * offline, just ignore these and we also need to set - * decrementers_next_tb as MAX to make sure __check_irq_replay - * don't replay timer interrupt when return, otherwise we'll trap - * here infinitely :( + /* + * Some implementations of hotplug will get timer interrupts while + * offline, just ignore these. */ if (unlikely(!cpu_online(smp_processor_id()))) { - *next_tb = ~(u64)0; set_dec(decrementer_max); return; } @@ -855,95 +853,6 @@ static notrace u64 timebase_read(struct clocksource *cs) return (u64)get_tb(); } - -void update_vsyscall(struct timekeeper *tk) -{ - struct timespec64 xt; - struct clocksource *clock = tk->tkr_mono.clock; - u32 mult = tk->tkr_mono.mult; - u32 shift = tk->tkr_mono.shift; - u64 cycle_last = tk->tkr_mono.cycle_last; - u64 new_tb_to_xs, new_stamp_xsec; - u64 frac_sec; - - if (clock != &clocksource_timebase) - return; - - xt.tv_sec = tk->xtime_sec; - xt.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); - - /* Make userspace gettimeofday spin until we're done. */ - ++vdso_data->tb_update_count; - smp_mb(); - - /* - * This computes ((2^20 / 1e9) * mult) >> shift as a - * 0.64 fixed-point fraction. - * The computation in the else clause below won't overflow - * (as long as the timebase frequency is >= 1.049 MHz) - * but loses precision because we lose the low bits of the constant - * in the shift. Note that 19342813113834067 ~= 2^(20+64) / 1e9. - * For a shift of 24 the error is about 0.5e-9, or about 0.5ns - * over a second. (Shift values are usually 22, 23 or 24.) - * For high frequency clocks such as the 512MHz timebase clock - * on POWER[6789], the mult value is small (e.g. 32768000) - * and so we can shift the constant by 16 initially - * (295147905179 ~= 2^(20+64-16) / 1e9) and then do the - * remaining shifts after the multiplication, which gives a - * more accurate result (e.g. with mult = 32768000, shift = 24, - * the error is only about 1.2e-12, or 0.7ns over 10 minutes). - */ - if (mult <= 62500000 && clock->shift >= 16) - new_tb_to_xs = ((u64) mult * 295147905179ULL) >> (clock->shift - 16); - else - new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift); - - /* - * Compute the fractional second in units of 2^-32 seconds. - * The fractional second is tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift - * in nanoseconds, so multiplying that by 2^32 / 1e9 gives - * it in units of 2^-32 seconds. - * We assume shift <= 32 because clocks_calc_mult_shift() - * generates shift values in the range 0 - 32. - */ - frac_sec = tk->tkr_mono.xtime_nsec << (32 - shift); - do_div(frac_sec, NSEC_PER_SEC); - - /* - * Work out new stamp_xsec value for any legacy users of systemcfg. - * stamp_xsec is in units of 2^-20 seconds. - */ - new_stamp_xsec = frac_sec >> 12; - new_stamp_xsec += tk->xtime_sec * XSEC_PER_SEC; - - /* - * tb_update_count is used to allow the userspace gettimeofday code - * to assure itself that it sees a consistent view of the tb_to_xs and - * stamp_xsec variables. It reads the tb_update_count, then reads - * tb_to_xs and stamp_xsec and then reads tb_update_count again. If - * the two values of tb_update_count match and are even then the - * tb_to_xs and stamp_xsec values are consistent. If not, then it - * loops back and reads them again until this criteria is met. - */ - vdso_data->tb_orig_stamp = cycle_last; - vdso_data->stamp_xsec = new_stamp_xsec; - vdso_data->tb_to_xs = new_tb_to_xs; - vdso_data->wtom_clock_sec = tk->wall_to_monotonic.tv_sec; - vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec; - vdso_data->stamp_xtime_sec = xt.tv_sec; - vdso_data->stamp_xtime_nsec = xt.tv_nsec; - vdso_data->stamp_sec_fraction = frac_sec; - vdso_data->hrtimer_res = hrtimer_resolution; - smp_wmb(); - ++(vdso_data->tb_update_count); -} - -void update_vsyscall_tz(void) -{ - vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; - vdso_data->tz_dsttime = sys_tz.tz_dsttime; -} - static void __init clocksource_init(void) { struct clocksource *clock = &clocksource_timebase; @@ -1103,7 +1012,6 @@ void __init time_init(void) sys_tz.tz_dsttime = 0; } - vdso_data->tb_update_count = 0; vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; /* initialise and enable the large decrementer (if we have one) */ |