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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-05 11:59:05 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-05 11:59:05 -0700 |
| commit | 9f0346dcbea363787186c94ef94dd01aaa215afa (patch) | |
| tree | b81c168f4d0dbe4c7f4750f4598d48a6deb72094 /arch/um/os-Linux/time.c | |
| download | linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip | |
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich:
- Fix kernfs listxattr() not returning security xattr names (e.g.
SELinux labels) when the kernfs node has no allocated kernfs_iattrs
- Fix silent truncation of IRQ vector indices in the Rust PCI
abstractions
- Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is
disabled instead of silently enabling extra kernel functionality
- Russ Weight is retiring from kernel development; update the Firmware
Loader sysfs contact to the driver-core mailing list, add a CREDITS
entry for Firmware Upload, and update MAINTAINERS accordingly
* tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
MAINTAINERS: Remove Russ Weight from Firmware Loader
CREDITS: Add CREDITS entry for Firmware Upload
firmware_loader: Change contact for sysfs nodes
rust: pci: reject IRQ vector indices that do not fit in u32
kernfs: preserve security xattrs without allocating iattrs
drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'arch/um/os-Linux/time.c')
| -rw-r--r-- | arch/um/os-Linux/time.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c new file mode 100644 index 000000000..13ebc8691 --- /dev/null +++ b/arch/um/os-Linux/time.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk}) + * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de) + * Copyright (C) 2012-2014 Cisco Systems + * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com) + */ + +#include <stddef.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> +#include <time.h> +#include <sys/signalfd.h> +#include <sys/time.h> +#include <kern_util.h> +#include <os.h> +#include <smp.h> +#include <string.h> +#include "internal.h" + +static timer_t event_high_res_timer[CONFIG_NR_CPUS] = { 0 }; + +static inline long long timespec_to_ns(const struct timespec *ts) +{ + return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) + ts->tv_nsec; +} + +long long os_persistent_clock_emulation(void) +{ + struct timespec realtime_tp; + + clock_gettime(CLOCK_REALTIME, &realtime_tp); + return timespec_to_ns(&realtime_tp); +} + +#ifndef sigev_notify_thread_id +#define sigev_notify_thread_id _sigev_un._tid +#endif + +/** + * os_timer_create() - create an new posix (interval) timer + */ +int os_timer_create(void) +{ + int cpu = uml_curr_cpu(); + timer_t *t = &event_high_res_timer[cpu]; + struct sigevent sev = { + .sigev_notify = SIGEV_THREAD_ID, + .sigev_signo = SIGALRM, + .sigev_value.sival_ptr = t, + .sigev_notify_thread_id = gettid(), + }; + + if (timer_create(CLOCK_MONOTONIC, &sev, t) == -1) + return -1; + + return 0; +} + +int os_timer_set_interval(int cpu, unsigned long long nsecs) +{ + struct itimerspec its; + + its.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC; + its.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC; + + its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC; + its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC; + + if (timer_settime(event_high_res_timer[cpu], 0, &its, NULL) == -1) + return -errno; + + return 0; +} + +int os_timer_one_shot(int cpu, unsigned long long nsecs) +{ + struct itimerspec its = { + .it_value.tv_sec = nsecs / UM_NSEC_PER_SEC, + .it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC, + + .it_interval.tv_sec = 0, + .it_interval.tv_nsec = 0, // we cheat here + }; + + timer_settime(event_high_res_timer[cpu], 0, &its, NULL); + return 0; +} + +/** + * os_timer_disable() - disable the posix (interval) timer + * @cpu: the CPU for which the timer is to be disabled + */ +void os_timer_disable(int cpu) +{ + struct itimerspec its; + + memset(&its, 0, sizeof(struct itimerspec)); + timer_settime(event_high_res_timer[cpu], 0, &its, NULL); +} + +long long os_nsecs(void) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC,&ts); + return timespec_to_ns(&ts); +} + +static __thread int wake_signals; + +void os_idle_prepare(void) +{ + sigset_t set; + + sigemptyset(&set); + sigaddset(&set, SIGALRM); + sigaddset(&set, IPI_SIGNAL); + + /* + * We need to use signalfd rather than sigsuspend in idle sleep + * because the IPI signal is a real-time signal that carries data, + * and unlike handling SIGALRM, we cannot simply flag it in + * signals_pending. + */ + wake_signals = signalfd(-1, &set, SFD_CLOEXEC); + if (wake_signals < 0) + panic("Failed to create signal FD, errno = %d", errno); +} + +/** + * os_idle_sleep() - sleep until interrupted + */ +void os_idle_sleep(void) +{ + sigset_t set; + + /* + * Block SIGALRM while performing the need_resched check. + * Note that, because IRQs are disabled, the IPI signal is + * already blocked. + */ + sigemptyset(&set); + sigaddset(&set, SIGALRM); + sigprocmask(SIG_BLOCK, &set, NULL); + + /* + * Because disabling IRQs does not block SIGALRM, it is also + * necessary to check for any pending timer alarms. + */ + if (!uml_need_resched() && !timer_alarm_pending()) + os_poll(1, &wake_signals); + + /* Restore the signal mask. */ + sigprocmask(SIG_UNBLOCK, &set, NULL); +} |
