Am Sonntag, den 31.05.2015, 20:10 +0100 schrieb Anton Ivanov:
> On 31/05/15 20:00, Thomas Meyer wrote:
> > Am Sonntag, den 31.05.2015, 13:15 +0200 schrieb Richard Weinberger:
> > > Am 20.05.2015 um 07:26 schrieb Thomas Meyer:
> > > > Am 20.05.2015 12:12 vorm. schrieb Richard Weinberger <
> > > > richard.weinber...@gmail.com>:
> > > > > On Sun, May 17, 2015 at 11:25 AM, Thomas Meyer <
> > > > > tho...@m3y3r.de>
> > > > > wrote:
> > > > > > Switch the UML clocksource from interval timers to posix
> > > > > > interval timers
> > > > > > and move to a monotonic timer.
> > > > > >
> > > > > > This fixes suspend&resume related timer issues and improves
> > > > > >
> > > > > > network
> > > > > > performance as TCP state machines are now fed with the
> > > > > > correct
> > > > > > time;
> > > > > > also correct QoS and traffic shaping.
> > > > > >
> > > > > > Signed-off-by: Thomas Meyer <tho...@m3y3r.de>
> > > > > What tree is this patch against?
> > > > > It does not clearly apply to Linus' tree.
> > > > >
> > > > Hi,
> > > >
> > > > I did tested the patch against 4.1-rc3-something; will update
> > > > the
> > > > patch against the latest commit!
> > Hi,
> >
> > > Ping.
> > > Would be nice to have this patch for the 4.2 merge window.
> > I can provide you the current version of the patch, but I'm not
> > sure if
> > it's ready for inclusion yet.
>
> Agree.
>
> > For example:
> > - With this patch I see new zombie processes of UML userspace
> > processes. I'm not sure what's going on here.
>
> +1
>
> > - Anton reported some hang he sees with this patch
>
> I did not have a chance to work on it last week, will try to find
> some
> time this week.
>
> > - A person from cicso is worried about the potential idle CPU usage
> > after the patch, because of the many timers started, i.e. a host
> > with
> > hundreds of UMLs.
> This is less then the old CPU usage - checking time and rearming
> nanosleeps and itimers is expensive.
>
> >
> > Also meanwhile I think is not the correct thing to start a new
> > timer
> > for each UML userspace process, because the timer will also trigger
> > the
> > userspace process, even the corresponding process isn't scheduled
> > by
> > the kernel currently. I think the previous behaviour with the
> > itimer
> > was okay, because the virtual timer only did execute when the
> > process
> > was executing which is the correct thing to do for the currently
> > active
> > task in the UML kernel.
> > I see two solutions for above problem: cascade the kernel timer
> > into
> > the current active task; there is actually no need to start a timer
> > in
> > each userspace process.
> > Start/stop each timer when a userspace process becomes active resp.
> > becomes inactive again.
> > I hope above logic makes some sense at all! What do you think about
> > this?
>
> Cascading the kernel timer looks like the correct solution.
Hi,
below patch get's rid of all userspace timers.
When a kernel timer interrupt is received the userspace process of the
corresponding task is signaled via SIGALRM.
The SIGALRM signal forces the userspace process to go back into
userspace() function. There the SIGALRM signal is ignored as the
interrupt was already processed anyway by the uml kernel.
what do you think about this approach?
Can you give this patch a try
with kind regards
thomas
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 17d4460..a4a434f 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -130,7 +130,7 @@ export LDS_ELF_FORMAT := $(ELF_FORMAT)
# The wrappers will select whether using "malloc" or the kernel allocator.
LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc
-LD_FLAGS_CMDLINE = $(foreach opt,$(LDFLAGS),-Wl,$(opt))
+LD_FLAGS_CMDLINE = $(foreach opt,$(LDFLAGS),-Wl,$(opt)) -lrt
# Used by link-vmlinux.sh which has special support for um link
export CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index d824528..8f8f5d7 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -183,6 +183,7 @@ extern int create_mem_file(unsigned long long len);
/* process.c */
extern unsigned long os_process_pc(int pid);
extern int os_process_parent(int pid);
+extern void os_alarm_process(int pid);
extern void os_stop_process(int pid);
extern void os_kill_process(int pid, int reap_child);
extern void os_kill_ptraced_process(int pid, int reap_child);
@@ -217,7 +218,7 @@ extern int set_umid(char *name);
extern char *get_umid(void);
/* signal.c */
-extern void timer_init(void);
+extern void timer_set_signal_handler(void);
extern void set_sigstack(void *sig_stack, int size);
extern void remove_sigstack(void);
extern void set_handler(int sig);
@@ -238,12 +239,16 @@ extern void um_early_printk(const char *s, unsigned int
n);
extern void os_fix_helper_signals(void);
/* time.c */
-extern void idle_sleep(unsigned long long nsecs);
-extern int set_interval(void);
-extern int timer_one_shot(int ticks);
-extern long long disable_timer(void);
+extern void os_idle_sleep(unsigned long long nsecs);
+extern int os_timer_create(void* timer);
+extern int os_timer_set_interval(void* timer, void* its);
+extern int os_timer_one_shot(int ticks);
+extern long long os_timer_disable(void);
+extern long os_timer_remain(void* timer);
extern void uml_idle_timer(void);
+extern long long os_persistent_clock_emulation(void);
extern long long os_nsecs(void);
+extern long long os_vnsecs(void);
/* skas/mem.c */
extern long run_syscall_stub(struct mm_id * mm_idp,
diff --git a/arch/um/include/shared/skas/stub-data.h
b/arch/um/include/shared/skas/stub-data.h
index f6ed92c..e09d8fd 100644
--- a/arch/um/include/shared/skas/stub-data.h
+++ b/arch/um/include/shared/skas/stub-data.h
@@ -6,12 +6,11 @@
#ifndef __STUB_DATA_H
#define __STUB_DATA_H
-#include <sys/time.h>
+#include <time.h>
struct stub_data {
- long offset;
+ unsigned long offset;
int fd;
- struct itimerval timer;
long err;
};
diff --git a/arch/um/include/shared/timer-internal.h
b/arch/um/include/shared/timer-internal.h
new file mode 100644
index 0000000..03e6f21
--- /dev/null
+++ b/arch/um/include/shared/timer-internal.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2012 - 2014 Cisco Systems
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __TIMER_INTERNAL_H__
+#define __TIMER_INTERNAL_H__
+
+#define TIMER_MULTIPLIER 256
+#define TIMER_MIN_DELTA 500
+
+#endif
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 68b9119..2ce38c1 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -27,6 +27,7 @@
#include <kern_util.h>
#include <os.h>
#include <skas.h>
+#include <timer-internal.h>
/*
* This is a per-cpu array. A processor only modifies its entry and it only
@@ -201,11 +202,8 @@ void initial_thread_cb(void (*proc)(void *), void *arg)
void arch_cpu_idle(void)
{
- unsigned long long nsecs;
-
cpu_tasks[current_thread_info()->cpu].pid = os_getpid();
- nsecs = disable_timer();
- idle_sleep(nsecs);
+ os_idle_sleep(UM_NSEC_PER_SEC);
local_irq_enable();
}
diff --git a/arch/um/kernel/skas/clone.c b/arch/um/kernel/skas/clone.c
index 289771d..498148b 100644
--- a/arch/um/kernel/skas/clone.c
+++ b/arch/um/kernel/skas/clone.c
@@ -35,11 +35,6 @@ stub_clone_handler(void)
if (err)
goto out;
- err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
- (long) &data->timer, 0);
- if (err)
- goto out;
-
remap_stack(data->fd, data->offset);
goto done;
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 117568d..29f1125 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2012-2014 Cisco Systems
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
@@ -7,11 +8,15 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
#include <linux/threads.h>
#include <asm/irq.h>
#include <asm/param.h>
#include <kern_util.h>
#include <os.h>
+#include <timer-internal.h>
void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs
*regs)
{
@@ -22,18 +27,20 @@ void timer_handler(int sig, struct siginfo *unused_si,
struct uml_pt_regs *regs)
local_irq_restore(flags);
}
-static void itimer_set_mode(enum clock_event_mode mode,
+static void timer_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- set_interval();
+ os_timer_set_interval(NULL, NULL);
break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ os_timer_one_shot(1);
+
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_ONESHOT:
- disable_timer();
+ os_timer_disable();
break;
case CLOCK_EVT_MODE_RESUME:
@@ -41,68 +48,79 @@ static void itimer_set_mode(enum clock_event_mode mode,
}
}
-static int itimer_next_event(unsigned long delta,
+static int timer_next_event(unsigned long delta,
struct clock_event_device *evt)
{
- return timer_one_shot(delta + 1);
+ return os_timer_one_shot(delta);
}
-static struct clock_event_device itimer_clockevent = {
- .name = "itimer",
+static struct clock_event_device timer_clockevent = {
+ .name = "posix-timer",
.rating = 250,
.cpumask = cpu_all_mask,
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
- .set_mode = itimer_set_mode,
- .set_next_event = itimer_next_event,
- .shift = 32,
+ .set_mode = timer_set_mode,
+ .set_next_event = timer_next_event,
+ .shift = 0,
+ .max_delta_ns = 0xffffffff,
+ .min_delta_ns = TIMER_MIN_DELTA, //microsecond resolution should be
enough for anyone, same as 640K RAM
.irq = 0,
+ .mult = 1,
};
-static irqreturn_t um_timer(int irq, void *dev)
+static irqreturn_t um_timer_irq(int irq, void *dev)
{
- (*itimer_clockevent.event_handler)(&itimer_clockevent);
+ if (get_current()->mm != NULL)
+ {
+ os_alarm_process(get_current()->mm->context.id.u.pid);
+ }
+
+ (*timer_clockevent.event_handler)(&timer_clockevent);
return IRQ_HANDLED;
}
-static cycle_t itimer_read(struct clocksource *cs)
+static cycle_t timer_read(struct clocksource *cs)
{
- return os_nsecs() / 1000;
+ return os_nsecs() / TIMER_MULTIPLIER;
}
-static struct clocksource itimer_clocksource = {
- .name = "itimer",
+static struct clocksource timer_clocksource = {
+ .name = "timer",
.rating = 300,
- .read = itimer_read,
+ .read = timer_read,
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static void __init setup_itimer(void)
+static void __init timer_setup(void)
{
int err;
- err = request_irq(TIMER_IRQ, um_timer, 0, "timer", NULL);
- if (err != 0)
+ err = request_irq(TIMER_IRQ, um_timer_irq, IRQF_TIMER, "hr timer",
NULL);
+ if (err != 0) {
printk(KERN_ERR "register_timer : request_irq failed - "
"errno = %d\n", -err);
+ return;
+ }
+
+ err = os_timer_create(NULL);
+ if (err != 0) {
+ printk(KERN_ERR "creation of timer failed - errno = %d\n", -err);
+ return;
+ }
- itimer_clockevent.mult = div_sc(HZ, NSEC_PER_SEC, 32);
- itimer_clockevent.max_delta_ns =
- clockevent_delta2ns(60 * HZ, &itimer_clockevent);
- itimer_clockevent.min_delta_ns =
- clockevent_delta2ns(1, &itimer_clockevent);
- err = clocksource_register_hz(&itimer_clocksource, USEC_PER_SEC);
+ err = clocksource_register_hz(&timer_clocksource,
NSEC_PER_SEC/TIMER_MULTIPLIER);
if (err) {
printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
return;
}
- clockevents_register_device(&itimer_clockevent);
+ clockevents_register_device(&timer_clockevent);
}
void read_persistent_clock(struct timespec *ts)
{
- long long nsecs = os_nsecs();
+ long long nsecs = os_persistent_clock_emulation();
set_normalized_timespec(ts, nsecs / NSEC_PER_SEC,
nsecs % NSEC_PER_SEC);
@@ -110,6 +128,6 @@ void read_persistent_clock(struct timespec *ts)
void __init time_init(void)
{
- timer_init();
- late_time_init = setup_itimer;
+ timer_set_signal_handler();
+ late_time_init = timer_setup;
}
diff --git a/arch/um/os-Linux/internal.h b/arch/um/os-Linux/internal.h
deleted file mode 100644
index 0dc2c9f..0000000
--- a/arch/um/os-Linux/internal.h
+++ /dev/null
@@ -1 +0,0 @@
-void alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc);
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index df9191a..6e36f0f 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -163,13 +163,13 @@ int __init main(int argc, char **argv, char **envp)
/*
* This signal stuff used to be in the reboot case. However,
- * sometimes a SIGVTALRM can come in when we're halting (reproducably
+ * sometimes a timer signal can come in when we're halting (reproducably
* when writing out gcov information, presumably because that takes
* some time) and cause a segfault.
*/
- /* stop timers and set SIGVTALRM to be ignored */
- disable_timer();
+ /* stop timers and set timer signal to be ignored */
+ os_timer_disable();
/* disable SIGIO for the fds and set SIGIO to be ignored */
err = deactivate_all_fds();
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index 8408aba..f3bd983 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -89,6 +89,11 @@ int os_process_parent(int pid)
return parent;
}
+void os_alarm_process(int pid)
+{
+ kill(pid, SIGALRM);
+}
+
void os_stop_process(int pid)
{
kill(pid, SIGSTOP);
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index 7b605e4..4a9be55 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -13,7 +13,6 @@
#include <kern_util.h>
#include <os.h>
#include <sysdep/mcontext.h>
-#include "internal.h"
void (*sig_info[NSIG])(int, struct siginfo *, struct uml_pt_regs *) = {
[SIGTRAP] = relay_signal,
@@ -23,7 +22,8 @@ void (*sig_info[NSIG])(int, struct siginfo *, struct
uml_pt_regs *) = {
[SIGBUS] = bus_handler,
[SIGSEGV] = segv_handler,
[SIGIO] = sigio_handler,
- [SIGVTALRM] = timer_handler };
+ [SIGALRM] = timer_handler
+};
static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc)
{
@@ -38,7 +38,7 @@ static void sig_handler_common(int sig, struct siginfo *si,
mcontext_t *mc)
}
/* enable signals if sig isn't IRQ signal */
- if ((sig != SIGIO) && (sig != SIGWINCH) && (sig != SIGVTALRM))
+ if ((sig != SIGIO) && (sig != SIGWINCH) && (sig != SIGALRM))
unblock_signals();
(*sig_info[sig])(sig, si, &r);
@@ -55,8 +55,8 @@ static void sig_handler_common(int sig, struct siginfo *si,
mcontext_t *mc)
#define SIGIO_BIT 0
#define SIGIO_MASK (1 << SIGIO_BIT)
-#define SIGVTALRM_BIT 1
-#define SIGVTALRM_MASK (1 << SIGVTALRM_BIT)
+#define SIGALRM_BIT 1
+#define SIGALRM_MASK (1 << SIGALRM_BIT)
static int signals_enabled;
static unsigned int signals_pending;
@@ -78,46 +78,47 @@ void sig_handler(int sig, struct siginfo *si, mcontext_t
*mc)
set_signals(enabled);
}
-static void real_alarm_handler(mcontext_t *mc)
+static void timer_real_alarm_handler(mcontext_t *mc)
{
struct uml_pt_regs regs;
if (mc != NULL)
get_regs_from_mc(®s, mc);
regs.is_user = 0;
- unblock_signals();
- timer_handler(SIGVTALRM, NULL, ®s);
+ timer_handler(SIGALRM, NULL, ®s);
}
-void alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc)
+void timer_alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc)
{
int enabled;
enabled = signals_enabled;
if (!signals_enabled) {
- signals_pending |= SIGVTALRM_MASK;
+ signals_pending |= SIGALRM_MASK;
return;
}
block_signals();
-
- real_alarm_handler(mc);
+ timer_real_alarm_handler(mc);
set_signals(enabled);
}
-void timer_init(void)
+void timer_set_signal_handler(void)
{
- set_handler(SIGVTALRM);
+ set_handler(SIGALRM);
}
void set_sigstack(void *sig_stack, int size)
{
- stack_t stack = ((stack_t) { .ss_flags = 0,
- .ss_sp = (__ptr_t) sig_stack,
- .ss_size = size - sizeof(void *) });
+ stack_t stack = ((stack_t) {
+ .ss_flags = 0,
+ .ss_sp = (__ptr_t) sig_stack,
+ .ss_size = size - sizeof(void *)
+ });
- if (sigaltstack(&stack, NULL) != 0)
+ if (sigaltstack(&stack, NULL) != 0) {
panic("enabling signal stack failed, errno = %d\n", errno);
+ }
}
static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
@@ -129,10 +130,9 @@ static void (*handlers[_NSIG])(int sig, struct siginfo
*si, mcontext_t *mc) = {
[SIGIO] = sig_handler,
[SIGWINCH] = sig_handler,
- [SIGVTALRM] = alarm_handler
+ [SIGALRM] = timer_alarm_handler
};
-
static void hard_handler(int sig, siginfo_t *si, void *p)
{
struct ucontext *uc = p;
@@ -186,9 +186,9 @@ void set_handler(int sig)
/* block irq ones */
sigemptyset(&action.sa_mask);
- sigaddset(&action.sa_mask, SIGVTALRM);
sigaddset(&action.sa_mask, SIGIO);
sigaddset(&action.sa_mask, SIGWINCH);
+ sigaddset(&action.sa_mask, SIGALRM);
if (sig == SIGSEGV)
flags |= SA_NODEFER;
@@ -281,8 +281,8 @@ void unblock_signals(void)
if (save_pending & SIGIO_MASK)
sig_handler_common(SIGIO, NULL, NULL);
- if (save_pending & SIGVTALRM_MASK)
- real_alarm_handler(NULL);
+ if (save_pending & SIGALRM_MASK)
+ timer_real_alarm_handler(NULL);
}
}
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 7a97775..2caada3 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -45,7 +45,7 @@ static int ptrace_dump_regs(int pid)
* Signals that are OK to receive in the stub - we'll just continue it.
* SIGWINCH will happen when UML is inside a detached screen.
*/
-#define STUB_SIG_MASK ((1 << SIGVTALRM) | (1 << SIGWINCH))
+#define STUB_SIG_MASK ((1 << SIGALRM) | (1 << SIGWINCH))
/* Signals that the stub will finish with - anything else is an error */
#define STUB_DONE_MASK (1 << SIGTRAP)
@@ -179,19 +179,13 @@ extern int __syscall_stub_start;
static int userspace_tramp(void *stack)
{
void *addr;
- int err, fd;
+ int fd;
unsigned long long offset;
ptrace(PTRACE_TRACEME, 0, 0, 0);
signal(SIGTERM, SIG_DFL);
signal(SIGWINCH, SIG_IGN);
- err = set_interval();
- if (err) {
- printk(UM_KERN_ERR "userspace_tramp - setting timer failed, "
- "errno = %d\n", err);
- exit(1);
- }
/*
* This has a pte, but it can't be mapped in with the usual
@@ -282,7 +276,7 @@ int start_userspace(unsigned long stub_stack)
"errno = %d\n", errno);
goto out_kill;
}
- } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
+ } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGALRM));
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) {
err = -EINVAL;
@@ -315,8 +309,6 @@ int start_userspace(unsigned long stub_stack)
void userspace(struct uml_pt_regs *regs)
{
- struct itimerval timer;
- unsigned long long nsecs, now;
int err, status, op, pid = userspace_pid[0];
/* To prevent races if using_sysemu changes under us.*/
int local_using_sysemu;
@@ -325,13 +317,8 @@ void userspace(struct uml_pt_regs *regs)
/* Handle any immediate reschedules or signals */
interrupt_end();
- if (getitimer(ITIMER_VIRTUAL, &timer))
- printk(UM_KERN_ERR "Failed to get itimer, errno = %d\n", errno);
- nsecs = timer.it_value.tv_sec * UM_NSEC_PER_SEC +
- timer.it_value.tv_usec * UM_NSEC_PER_USEC;
- nsecs += os_nsecs();
-
while (1) {
+
/*
* This can legitimately fail if the process loads a
* bogus value into a segment register. It will
@@ -401,18 +388,7 @@ void userspace(struct uml_pt_regs *regs)
case SIGTRAP:
relay_signal(SIGTRAP, (struct siginfo *)&si,
regs);
break;
- case SIGVTALRM:
- now = os_nsecs();
- if (now < nsecs)
- break;
- block_signals();
- (*sig_info[sig])(sig, (struct siginfo *)&si,
regs);
- unblock_signals();
- nsecs = timer.it_value.tv_sec *
- UM_NSEC_PER_SEC +
- timer.it_value.tv_usec *
- UM_NSEC_PER_USEC;
- nsecs += os_nsecs();
+ case SIGALRM:
break;
case SIGIO:
case SIGILL:
@@ -460,7 +436,6 @@ __initcall(init_thread_regs);
int copy_context_skas0(unsigned long new_stack, int pid)
{
- struct timeval tv = { .tv_sec = 0, .tv_usec = UM_USEC_PER_SEC / UM_HZ };
int err;
unsigned long current_stack = current_stub_stack();
struct stub_data *data = (struct stub_data *) current_stack;
@@ -472,11 +447,10 @@ int copy_context_skas0(unsigned long new_stack, int pid)
* prepare offset and fd of child's stack as argument for parent's
* and child's mmap2 calls
*/
- *data = ((struct stub_data) { .offset = MMAP_OFFSET(new_offset),
- .fd = new_fd,
- .timer = ((struct itimerval)
- { .it_value = tv,
- .it_interval = tv }) });
+ *data = ((struct stub_data) {
+ .offset = MMAP_OFFSET(new_offset),
+ .fd = new_fd
+ });
err = ptrace_setregs(pid, thread_regs);
if (err < 0) {
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index e9824d5..0e2bb7d 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2012-2014 Cisco Systems
* Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
@@ -10,177 +11,172 @@
#include <sys/time.h>
#include <kern_util.h>
#include <os.h>
-#include "internal.h"
+#include <string.h>
+#include <timer-internal.h>
-int set_interval(void)
-{
- int usec = UM_USEC_PER_SEC / UM_HZ;
- struct itimerval interval = ((struct itimerval) { { 0, usec },
- { 0, usec } });
-
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+static timer_t event_high_res_timer = 0;
- return 0;
+static inline long long timeval_to_ns(const struct timeval *tv)
+{
+ return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
+ tv->tv_usec * UM_NSEC_PER_USEC;
}
-int timer_one_shot(int ticks)
+static inline long long timespec_to_ns(const struct timespec *ts)
{
- unsigned long usec = ticks * UM_USEC_PER_SEC / UM_HZ;
- unsigned long sec = usec / UM_USEC_PER_SEC;
- struct itimerval interval;
-
- usec %= UM_USEC_PER_SEC;
- interval = ((struct itimerval) { { 0, 0 }, { sec, usec } });
+ return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) +
+ ts->tv_nsec;
+}
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+long long os_persistent_clock_emulation (void) {
+ struct timespec realtime_tp;
- return 0;
+ clock_gettime(CLOCK_REALTIME, &realtime_tp);
+ return timespec_to_ns(&realtime_tp);
}
/**
- * timeval_to_ns - Convert timeval to nanoseconds
- * @ts: pointer to the timeval variable to be converted
- *
- * Returns the scalar nanosecond representation of the timeval
- * parameter.
- *
- * Ripped from linux/time.h because it's a kernel header, and thus
- * unusable from here.
+ * os_timer_create() - create an new posix (interval) timer
*/
-static inline long long timeval_to_ns(const struct timeval *tv)
-{
- return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
- tv->tv_usec * UM_NSEC_PER_USEC;
+int os_timer_create(void* timer) {
+
+ timer_t* t = timer;
+
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
+
+ if (timer_create(
+ CLOCK_MONOTONIC,
+ NULL,
+ t) == -1) {
+ return -1;
+ }
+ return 0;
}
-long long disable_timer(void)
+int os_timer_set_interval(void* timer, void* i)
{
- struct itimerval time = ((struct itimerval) { { 0, 0 }, { 0, 0 } });
- long long remain, max = UM_NSEC_PER_SEC / UM_HZ;
+ struct itimerspec its;
+ unsigned long long nsec;
+ timer_t* t = timer;
+ struct itimerspec* its_in = i;
- if (setitimer(ITIMER_VIRTUAL, &time, &time) < 0)
- printk(UM_KERN_ERR "disable_timer - setitimer failed, "
- "errno = %d\n", errno);
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
- remain = timeval_to_ns(&time.it_value);
- if (remain > max)
- remain = max;
+ nsec = UM_NSEC_PER_SEC / UM_HZ;
- return remain;
-}
+ if(its_in != NULL) {
+ its.it_value.tv_sec = its_in->it_value.tv_sec;
+ its.it_value.tv_nsec = its_in->it_value.tv_nsec;
+ } else {
+ its.it_value.tv_sec = 0;
+ its.it_value.tv_nsec = nsec;
+ }
-long long os_nsecs(void)
-{
- struct timeval tv;
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = nsec;
- gettimeofday(&tv, NULL);
- return timeval_to_ns(&tv);
-}
+ if(timer_settime(*t, 0, &its, NULL) == -1) {
+ return -errno;
+ }
-#ifdef UML_CONFIG_NO_HZ_COMMON
-static int after_sleep_interval(struct timespec *ts)
-{
return 0;
}
-static void deliver_alarm(void)
+/**
+ * os_timer_remain() - returns the remaining nano seconds of the given interval
+ * timer
+ * Because this is the remaining time of an interval timer, which
correspondends
+ * to HZ, this value can never be bigger than one second. Just
+ * the nanosecond part of the timer is returned.
+ * The returned time is relative to the start time of the interval timer.
+ * Return an negative value in an error case.
+ */
+long os_timer_remain(void* timer)
{
- alarm_handler(SIGVTALRM, NULL, NULL);
-}
+ struct itimerspec its;
+ timer_t* t = timer;
-static unsigned long long sleep_time(unsigned long long nsecs)
-{
- return nsecs;
-}
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
-#else
-unsigned long long last_tick;
-unsigned long long skew;
+ if(timer_gettime(t, &its) == -1) {
+ return -errno;
+ }
+
+ return its.it_value.tv_nsec;
+}
-static void deliver_alarm(void)
+int os_timer_one_shot(int ticks)
{
- unsigned long long this_tick = os_nsecs();
- int one_tick = UM_NSEC_PER_SEC / UM_HZ;
+ struct itimerspec its;
+ unsigned long long nsec;
+ unsigned long sec;
- /* Protection against the host's time going backwards */
- if ((last_tick != 0) && (this_tick < last_tick))
- this_tick = last_tick;
+ nsec = (ticks + 1);
+ sec = nsec / UM_NSEC_PER_SEC;
+ nsec = nsec % UM_NSEC_PER_SEC;
- if (last_tick == 0)
- last_tick = this_tick - one_tick;
+ its.it_value.tv_sec = nsec / UM_NSEC_PER_SEC;
+ its.it_value.tv_nsec = nsec;
- skew += this_tick - last_tick;
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = 0; // we cheat here
- while (skew >= one_tick) {
- alarm_handler(SIGVTALRM, NULL, NULL);
- skew -= one_tick;
- }
-
- last_tick = this_tick;
+ timer_settime(event_high_res_timer, 0, &its, NULL);
+ return 0;
}
-static unsigned long long sleep_time(unsigned long long nsecs)
+/**
+ * os_timer_disable() - disable the posix (interval) timer
+ * Returns the remaining interval timer time in nanoseconds
+ */
+long long os_timer_disable(void)
{
- return nsecs > skew ? nsecs - skew : 0;
+ struct itimerspec its;
+
+ memset(&its, 0, sizeof(struct itimerspec));
+ timer_settime(event_high_res_timer, 0, &its, &its);
+
+ return its.it_value.tv_sec * UM_NSEC_PER_SEC + its.it_value.tv_nsec;
}
-static inline long long timespec_to_us(const struct timespec *ts)
+long long os_vnsecs(void)
{
- return ((long long) ts->tv_sec * UM_USEC_PER_SEC) +
- ts->tv_nsec / UM_NSEC_PER_USEC;
+ struct timespec ts;
+
+ clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&ts);
+ return timespec_to_ns(&ts);
}
-static int after_sleep_interval(struct timespec *ts)
+long long os_nsecs(void)
{
- int usec = UM_USEC_PER_SEC / UM_HZ;
- long long start_usecs = timespec_to_us(ts);
- struct timeval tv;
- struct itimerval interval;
-
- /*
- * It seems that rounding can increase the value returned from
- * setitimer to larger than the one passed in. Over time,
- * this will cause the remaining time to be greater than the
- * tick interval. If this happens, then just reduce the first
- * tick to the interval value.
- */
- if (start_usecs > usec)
- start_usecs = usec;
-
- start_usecs -= skew / UM_NSEC_PER_USEC;
- if (start_usecs < 0)
- start_usecs = 0;
-
- tv = ((struct timeval) { .tv_sec = start_usecs / UM_USEC_PER_SEC,
- .tv_usec = start_usecs % UM_USEC_PER_SEC });
- interval = ((struct itimerval) { { 0, usec }, tv });
-
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+ struct timespec ts;
- return 0;
+ clock_gettime(CLOCK_MONOTONIC,&ts);
+ return timespec_to_ns(&ts);
}
-#endif
-void idle_sleep(unsigned long long nsecs)
+/**
+ * os_idle_sleep() - sleep for a given time of nsecs
+ * @nsecs: nanoseconds to sleep
+ */
+void os_idle_sleep(unsigned long long nsecs)
{
struct timespec ts;
- /*
- * nsecs can come in as zero, in which case, this starts a
- * busy loop. To prevent this, reset nsecs to the tick
- * interval if it is zero.
- */
- if (nsecs == 0)
- nsecs = UM_NSEC_PER_SEC / UM_HZ;
-
- nsecs = sleep_time(nsecs);
- ts = ((struct timespec) { .tv_sec = nsecs / UM_NSEC_PER_SEC,
- .tv_nsec = nsecs % UM_NSEC_PER_SEC });
-
- if (nanosleep(&ts, &ts) == 0)
- deliver_alarm();
- after_sleep_interval(&ts);
+ if (nsecs <= 0) {
+ return;
+ }
+
+ ts = ((struct timespec) {
+ .tv_sec = nsecs / UM_NSEC_PER_SEC,
+ .tv_nsec = nsecs % UM_NSEC_PER_SEC
+ });
+
+ clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL);
}
--
2.4.1
------------------------------------------------------------------------------
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