| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
Move the p->nr_cpus_allowed check into kernel/sched/core.c: select_task_rq().
This change will make fair.c, rt.c, and deadline.c all start with the
same logic.
Suggested-and-Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: "pang.xunlei" <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
As discussed in [1], accounting IO is meant for blkio only. Document that
so driver authors won't use them for device io.
[1] http://thread.gmane.org/gmane.linux.drivers.i2c/20470
Signed-off-by: Wolfram Sang <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: One Thousand Gnomes <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Nobody iterates over numa_group::task_list, this just confuses the readers.
Signed-off-by: Kirill Tkhai <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/1415358456.28592.17.camel@tkhai
Signed-off-by: Ingo Molnar <[email protected]>
|
|
applying more changes
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Commit d670ec13178d0 "posix-cpu-timers: Cure SMP wobbles" fixes one glibc
test case in cost of breaking another one. After that commit, calling
clock_nanosleep(TIMER_ABSTIME, X) and then clock_gettime(&Y) can result
of Y time being smaller than X time.
Reproducer/tester can be found further below, it can be compiled and ran by:
gcc -o tst-cpuclock2 tst-cpuclock2.c -pthread
while ./tst-cpuclock2 ; do : ; done
This reproducer, when running on a buggy kernel, will complain
about "clock_gettime difference too small".
Issue happens because on start in thread_group_cputimer() we initialize
sum_exec_runtime of cputimer with threads runtime not yet accounted and
then add the threads runtime to running cputimer again on scheduler
tick, making it's sum_exec_runtime bigger than actual threads runtime.
KOSAKI Motohiro posted a fix for this problem, but that patch was never
applied: https://lkml.org/lkml/2013/5/26/191 .
This patch takes different approach to cure the problem. It calls
update_curr() when cputimer starts, that assure we will have updated
stats of running threads and on the next schedule tick we will account
only the runtime that elapsed from cputimer start. That also assure we
have consistent state between cpu times of individual threads and cpu
time of the process consisted by those threads.
Full reproducer (tst-cpuclock2.c):
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <stdio.h>
#include <time.h>
#include <pthread.h>
#include <stdint.h>
#include <inttypes.h>
/* Parameters for the Linux kernel ABI for CPU clocks. */
#define CPUCLOCK_SCHED 2
#define MAKE_PROCESS_CPUCLOCK(pid, clock) \
((~(clockid_t) (pid) << 3) | (clockid_t) (clock))
static pthread_barrier_t barrier;
/* Help advance the clock. */
static void *chew_cpu(void *arg)
{
pthread_barrier_wait(&barrier);
while (1) ;
return NULL;
}
/* Don't use the glibc wrapper. */
static int do_nanosleep(int flags, const struct timespec *req)
{
clockid_t clock_id = MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED);
return syscall(SYS_clock_nanosleep, clock_id, flags, req, NULL);
}
static int64_t tsdiff(const struct timespec *before, const struct timespec *after)
{
int64_t before_i = before->tv_sec * 1000000000ULL + before->tv_nsec;
int64_t after_i = after->tv_sec * 1000000000ULL + after->tv_nsec;
return after_i - before_i;
}
int main(void)
{
int result = 0;
pthread_t th;
pthread_barrier_init(&barrier, NULL, 2);
if (pthread_create(&th, NULL, chew_cpu, NULL) != 0) {
perror("pthread_create");
return 1;
}
pthread_barrier_wait(&barrier);
/* The test. */
struct timespec before, after, sleeptimeabs;
int64_t sleepdiff, diffabs;
const struct timespec sleeptime = {.tv_sec = 0,.tv_nsec = 100000000 };
/* The relative nanosleep. Not sure why this is needed, but its presence
seems to make it easier to reproduce the problem. */
if (do_nanosleep(0, &sleeptime) != 0) {
perror("clock_nanosleep");
return 1;
}
/* Get the current time. */
if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &before) < 0) {
perror("clock_gettime[2]");
return 1;
}
/* Compute the absolute sleep time based on the current time. */
uint64_t nsec = before.tv_nsec + sleeptime.tv_nsec;
sleeptimeabs.tv_sec = before.tv_sec + nsec / 1000000000;
sleeptimeabs.tv_nsec = nsec % 1000000000;
/* Sleep for the computed time. */
if (do_nanosleep(TIMER_ABSTIME, &sleeptimeabs) != 0) {
perror("absolute clock_nanosleep");
return 1;
}
/* Get the time after the sleep. */
if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &after) < 0) {
perror("clock_gettime[3]");
return 1;
}
/* The time after sleep should always be equal to or after the absolute sleep
time passed to clock_nanosleep. */
sleepdiff = tsdiff(&sleeptimeabs, &after);
if (sleepdiff < 0) {
printf("absolute clock_nanosleep woke too early: %" PRId64 "\n", sleepdiff);
result = 1;
printf("Before %llu.%09llu\n", before.tv_sec, before.tv_nsec);
printf("After %llu.%09llu\n", after.tv_sec, after.tv_nsec);
printf("Sleep %llu.%09llu\n", sleeptimeabs.tv_sec, sleeptimeabs.tv_nsec);
}
/* The difference between the timestamps taken before and after the
clock_nanosleep call should be equal to or more than the duration of the
sleep. */
diffabs = tsdiff(&before, &after);
if (diffabs < sleeptime.tv_nsec) {
printf("clock_gettime difference too small: %" PRId64 "\n", diffabs);
result = 1;
}
pthread_cancel(th);
return result;
}
Signed-off-by: Stanislaw Gruszka <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
While looking over the cpu-timer code I found that we appear to add
the delta for the calling task twice, through:
cpu_timer_sample_group()
thread_group_cputimer()
thread_group_cputime()
times->sum_exec_runtime += task_sched_runtime();
*sample = cputime.sum_exec_runtime + task_delta_exec();
Which would make the sample run ahead, making the sleep short.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Stanislaw Gruszka <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Tejun Heo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Because the whole numa task selection stuff runs with preemption
enabled (its long and expensive) we can end up migrating and selecting
oneself as a swap target. This doesn't really work out well -- we end
up trying to acquire the same lock twice for the swap migrate -- so
avoid this.
Reported-and-Tested-by: Sasha Levin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
When a CPU hotplugged out, we call perf_remove_from_context() (via
perf_event_exit_cpu()) to rip each CPU-bound event out of its PMU's cpu
context, but leave siblings grouped together. Freeing of these events is
left to the mercy of the usual refcounting.
When a CPU-bound event's refcount drops to zero we cross-call to
__perf_remove_from_context() to clean it up, detaching grouped siblings.
This works when the relevant CPU is online, but will fail if the CPU is
currently offline, and we won't detach the event from its siblings
before freeing the event, leaving the sibling list corrupt. If the
sibling list is later walked (e.g. because the CPU cam online again
before a remaining sibling's refcount drops to zero), we will walk the
now corrupted siblings list, potentially dereferencing garbage values.
Given that the events should never be scheduled again (as we removed
them from their context), we can simply detatch siblings when the CPU
goes down in the first place. If the CPU comes back online, the
redundant call to __perf_remove_from_context() is safe.
Reported-by: Drew Richardson <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: Vince Weaver <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
"These are three regression fixes, two recent (generic power domains,
suspend-to-idle) and one older (cpufreq), an ACPI blacklist entry for
one more machine having problems with Windows 8 compatibility, a minor
cpufreq driver fix (cpufreq-dt) and a fixup for new callback
definitions (generic power domains).
Specifics:
- Fix a crash in the suspend-to-idle code path introduced by a recent
commit that forgot to check a pointer against NULL before
dereferencing it (Dmitry Eremin-Solenikov).
- Fix a boot crash on Exynos5 introduced by a recent commit making
that platform use generic Device Tree bindings for power domains
which exposed a weakness in the generic power domains framework
leading to that crash (Ulf Hansson).
- Fix a crash during system resume on systems where cpufreq depends
on Operation Performance Points (OPP) for functionality, but
CONFIG_OPP is not set. This leads the cpufreq driver registration
to fail, but the resume code attempts to restore the pre-suspend
cpufreq configuration (which does not exist) nevertheless and
crashes. From Geert Uytterhoeven.
- Add a new ACPI blacklist entry for Dell Vostro 3546 that has
problems if it is reported as Windows 8 compatible to the BIOS
(Adam Lee).
- Fix swapped arguments in an error message in the cpufreq-dt driver
(Abhilash Kesavan).
- Fix up the prototypes of new callbacks in struct generic_pm_domain
to make them more useful. Users of those callbacks will be added
in 3.19 and it's better for them to be based on the correct struct
definition in mainline from the start. From Ulf Hansson and Kevin
Hilman"
* tag 'pm+acpi-3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / Domains: Fix initial default state of the need_restore flag
PM / sleep: Fix entering suspend-to-IDLE if no freeze_oops is set
PM / Domains: Change prototype for the attach and detach callbacks
cpufreq: Avoid crash in resume on SMP without OPP
cpufreq: cpufreq-dt: Fix arguments in clock failure error message
ACPI / blacklist: blacklist Win8 OSI for Dell Vostro 3546
|
|
Commit 69361eef9056 ("panic: add TAINT_SOFTLOCKUP") added the 'L' flag,
but failed to update the comments for print_tainted(). So, update the
comments.
Signed-off-by: Xie XiuQi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
|
|
'fixes.2014.11.13a', 'signal.2014.10.29a' and 'rt.2014.10.29a' into HEAD
cpu.2014.11.03a: Changes for per-CPU variables.
doc.2014.11.13a: Documentation updates.
fixes.2014.11.13a: Miscellaneous fixes.
signal.2014.10.29a: Signal changes.
rt.2014.10.29a: Real-time changes.
torture.2014.11.03a: torture-test changes.
|
|
This commit affines rcu_tasks_kthread() to the housekeeping CPUs
in CONFIG_NO_HZ_FULL builds. This is just a default, so systems
administrators are free to put this kthread somewhere else if they wish.
Signed-off-by: Paul E. McKenney <[email protected]>
|
|
Pull audit fixes from Paul Moore:
"After he sent the initial audit pull request for 3.18, Eric asked me
to take over the management of the audit tree, hence this pull request
to fix a couple of problems with audit.
As you can see below, the changes are minimal: adding some whitespace
to a string so userspace parses it correctly, and fixing a problem
with audit's usage of fsnotify that was causing audit watch rules to
be lost. Neither of these patches were very controversial on the
mailing lists and they fix real problems, getting them into 3.18 would
be a good thing"
* 'stable-3.18' of git://git.infradead.org/users/pcmoore/audit:
audit: keep inode pinned
audit: AUDIT_FEATURE_CHANGE message format missing delimiting space
|
|
Audit rules disappear when an inode they watch is evicted from the cache.
This is likely not what we want.
The guilty commit is "fsnotify: allow marks to not pin inodes in core",
which didn't take into account that audit_tree adds watches with a zero
mask.
Adding any mask should fix this.
Fixes: 90b1e7a57880 ("fsnotify: allow marks to not pin inodes in core")
Signed-off-by: Miklos Szeredi <[email protected]>
Cc: [email protected] # 2.6.36+
Signed-off-by: Paul Moore <[email protected]>
|
|
If the read loop in trace_buffers_splice_read() keeps failing due to
memory allocation failures without reading even a single page then this
function will keep busy looping.
Remove the risk for that by exiting the function if memory allocation
failures are seen.
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Rabin Vincent <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
|
|
On a !PREEMPT kernel, attempting to use trace-cmd results in a soft
lockup:
# trace-cmd record -e raw_syscalls:* -F false
NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [trace-cmd:61]
...
Call Trace:
[<ffffffff8105b580>] ? __wake_up_common+0x90/0x90
[<ffffffff81092e25>] wait_on_pipe+0x35/0x40
[<ffffffff810936e3>] tracing_buffers_splice_read+0x2e3/0x3c0
[<ffffffff81093300>] ? tracing_stats_read+0x2a0/0x2a0
[<ffffffff812d10ab>] ? _raw_spin_unlock+0x2b/0x40
[<ffffffff810dc87b>] ? do_read_fault+0x21b/0x290
[<ffffffff810de56a>] ? handle_mm_fault+0x2ba/0xbd0
[<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
[<ffffffff810951e2>] ? trace_buffer_lock_reserve+0x22/0x60
[<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
[<ffffffff8112415d>] do_splice_to+0x6d/0x90
[<ffffffff81126971>] SyS_splice+0x7c1/0x800
[<ffffffff812d1edd>] tracesys_phase2+0xd3/0xd8
The problem is this: tracing_buffers_splice_read() calls
ring_buffer_wait() to wait for data in the ring buffers. The buffers
are not empty so ring_buffer_wait() returns immediately. But
tracing_buffers_splice_read() calls ring_buffer_read_page() with full=1,
meaning it only wants to read a full page. When the full page is not
available, tracing_buffers_splice_read() tries to wait again with
ring_buffer_wait(), which again returns immediately, and so on.
Fix this by adding a "full" argument to ring_buffer_wait() which will
make ring_buffer_wait() wait until the writer has left the reader's
page, i.e. until full-page reads will succeed.
Link: http://lkml.kernel.org/r/[email protected]
Cc: [email protected] # 3.16+
Fixes: b1169cc69ba9 ("tracing: Remove mock up poll wait function")
Signed-off-by: Rabin Vincent <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
|
|
On latest mm + KASan patchset I've got this:
==================================================================
BUG: AddressSanitizer: out of bounds access in sched_init_smp+0x3ba/0x62c at addr ffff88006d4bee6c
=============================================================================
BUG kmalloc-8 (Not tainted): kasan error
-----------------------------------------------------------------------------
Disabling lock debugging due to kernel taint
INFO: Allocated in alloc_vfsmnt+0xb0/0x2c0 age=75 cpu=0 pid=0
__slab_alloc+0x4b4/0x4f0
__kmalloc_track_caller+0x15f/0x1e0
kstrdup+0x44/0x90
alloc_vfsmnt+0xb0/0x2c0
vfs_kern_mount+0x35/0x190
kern_mount_data+0x25/0x50
pid_ns_prepare_proc+0x19/0x50
alloc_pid+0x5e2/0x630
copy_process.part.41+0xdf5/0x2aa0
do_fork+0xf5/0x460
kernel_thread+0x21/0x30
rest_init+0x1e/0x90
start_kernel+0x522/0x531
x86_64_start_reservations+0x2a/0x2c
x86_64_start_kernel+0x15b/0x16a
INFO: Slab 0xffffea0001b52f80 objects=24 used=22 fp=0xffff88006d4befc0 flags=0x100000000004080
INFO: Object 0xffff88006d4bed20 @offset=3360 fp=0xffff88006d4bee70
Bytes b4 ffff88006d4bed10: 00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ
Object ffff88006d4bed20: 70 72 6f 63 00 6b 6b a5 proc.kk.
Redzone ffff88006d4bed28: cc cc cc cc cc cc cc cc ........
Padding ffff88006d4bee68: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B 3.18.0-rc3-mm1+ #108
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
ffff88006d4be000 0000000000000000 ffff88006d4bed20 ffff88006c86fd18
ffffffff81cd0a59 0000000000000058 ffff88006d404240 ffff88006c86fd48
ffffffff811fa3a8 ffff88006d404240 ffffea0001b52f80 ffff88006d4bed20
Call Trace:
dump_stack (lib/dump_stack.c:52)
print_trailer (mm/slub.c:645)
object_err (mm/slub.c:652)
? sched_init_smp (kernel/sched/core.c:6552 kernel/sched/core.c:7063)
kasan_report_error (mm/kasan/report.c:102 mm/kasan/report.c:178)
? kasan_poison_shadow (mm/kasan/kasan.c:48)
? kasan_unpoison_shadow (mm/kasan/kasan.c:54)
? kasan_poison_shadow (mm/kasan/kasan.c:48)
? kasan_kmalloc (mm/kasan/kasan.c:311)
__asan_load4 (mm/kasan/kasan.c:371)
? sched_init_smp (kernel/sched/core.c:6552 kernel/sched/core.c:7063)
sched_init_smp (kernel/sched/core.c:6552 kernel/sched/core.c:7063)
kernel_init_freeable (init/main.c:869 init/main.c:997)
? finish_task_switch (kernel/sched/sched.h:1036 kernel/sched/core.c:2248)
? rest_init (init/main.c:924)
kernel_init (init/main.c:929)
? rest_init (init/main.c:924)
ret_from_fork (arch/x86/kernel/entry_64.S:348)
? rest_init (init/main.c:924)
Read of size 4 by task swapper/0:
Memory state around the buggy address:
ffff88006d4beb80: fc fc fc fc fc fc fc fc fc fc 00 fc fc fc fc fc
ffff88006d4bec00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88006d4bec80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88006d4bed00: fc fc fc fc 00 fc fc fc fc fc fc fc fc fc fc fc
ffff88006d4bed80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88006d4bee00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc 04 fc
^
ffff88006d4bee80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88006d4bef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88006d4bef80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff88006d4bf000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88006d4bf080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Zero 'level' (e.g. on non-NUMA system) causing out of bounds
access in this line:
sched_max_numa_distance = sched_domains_numa_distance[level - 1];
Fix this by exiting from sched_init_numa() earlier.
Signed-off-by: Andrey Ryabinin <[email protected]>
Reviewed-by: Rik van Riel <[email protected]>
Fixes: 9942f79ba ("sched/numa: Export info needed for NUMA balancing on complex topologies")
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Use io{read,write}32be if the caller specified IRQ_GC_BE_IO when creating
the irqchip.
Signed-off-by: Kevin Cernekee <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Acked-by: Arnd Bergmann <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jason Cooper <[email protected]>
|
|
Pass in the irq_chip_generic struct so we can use different readl/writel
settings for each irqchip driver, when appropriate. Compute
(gc->reg_base + reg_offset) in the helper function because this is pretty
much what all callers want to do anyway.
Compile-tested using the following configurations:
at91_dt_defconfig (CONFIG_ATMEL_AIC_IRQ=y)
sama5_defconfig (CONFIG_ATMEL_AIC5_IRQ=y)
sunxi_defconfig (CONFIG_ARCH_SUNXI=y)
tb10x (ARC) is untested.
Signed-off-by: Kevin Cernekee <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Acked-by: Arnd Bergmann <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jason Cooper <[email protected]>
|
|
If no freeze_ops is set, trying to enter suspend-to-IDLE will cause a
nice oops in platform_suspend_prepare_late(). Add respective checks to
platform_suspend_prepare_late() and platform_resume_early() functions.
Fixes: a8d46b9e4e48 (ACPI / sleep: Rework the handling of ACPI GPE wakeup ...)
Signed-off-by: Dmitry Eremin-Solenikov <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
|
|
This patch simplifies task_struct by removing the four numa_* pointers
in the same array and replacing them with the array pointer. By doing this,
on x86_64, the size of task_struct is reduced by 3 ulong pointers (24 bytes on
x86_64).
A new parameter is added to the task_faults_idx function so that it can return
an index to the correct offset, corresponding with the old precalculated
pointers.
All of the code in sched/ that depended on task_faults_idx and numa_* was
changed in order to match the new logic.
Signed-off-by: Iulia Manda <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/20141031001331.GA30662@winterfell
Signed-off-by: Ingo Molnar <[email protected]>
|
|
There are both UP and SMP version of pull_dl_task(), so don't need
to check CONFIG_SMP in switched_from_dl();
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
In switched_from_dl() we have to issue a resched if we successfully
pulled some task from other cpus. This patch also aligns the behavior
with -rt.
Suggested-by: Juri Lelli <[email protected]>
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
This patch pushes task away if the dealine of the task is equal
to current during wake up. The same behavior as rt class.
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
This patch add deadline rq status print.
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
The yield semantic of deadline class is to reduce remaining runtime to
zero, and then update_curr_dl() will stop it. However, comsumed bandwidth
is reduced from the budget of yield task again even if it has already been
set to zero which leads to artificial overrun. This patch fix it by make
sure we don't steal some more time from the task that yielded in update_curr_dl().
Suggested-by: Juri Lelli <[email protected]>
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
This patch checks if current can be pushed/pulled somewhere else
in advance to make logic clear, the same behavior as dl class.
- If current can't be migrated, useless to reschedule, let's hope
task can move out.
- If task is migratable, so let's not schedule it and see if it
can be pushed or pulled somewhere else.
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
As per commit f10e00f4bf36 ("sched/dl: Use dl_bw_of() under
rcu_read_lock_sched()"), dl_bw_of() has to be protected by
rcu_read_lock_sched().
Signed-off-by: Juri Lelli <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
least_loaded_cpu
Idle cpu is idler than non-idle cpu, so we needn't search for least_loaded_cpu
after we have found an idle cpu.
Signed-off-by: Yao Dongdong <[email protected]>
Reviewed-by: Srikar Dronamraju <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Currently used hrtimer_try_to_cancel() is racy:
raw_spin_lock(&rq->lock)
... dl_task_timer raw_spin_lock(&rq->lock)
... raw_spin_lock(&rq->lock) ...
switched_from_dl() ... ...
hrtimer_try_to_cancel() ... ...
switched_to_fair() ... ...
... ... ...
... ... ...
raw_spin_unlock(&rq->lock) ... (asquired)
... ... ...
... ... ...
do_exit() ... ...
schedule() ... ...
raw_spin_lock(&rq->lock) ... raw_spin_unlock(&rq->lock)
... ... ...
raw_spin_unlock(&rq->lock) ... raw_spin_lock(&rq->lock)
... ... (asquired)
put_task_struct() ... ...
free_task_struct() ... ...
... ... raw_spin_unlock(&rq->lock)
... (asquired) ...
... ... ...
... (use after free) ...
So, let's implement 100% guaranteed way to cancel the timer and let's
be sure we are safe even in very unlikely situations.
rq unlocking does not limit the area of switched_from_dl() use, because
this has already been possible in pull_dl_task() below.
Let's consider the safety of of this unlocking. New code in the patch
is working when hrtimer_try_to_cancel() fails. This means the callback
is running. In this case hrtimer_cancel() is just waiting till the
callback is finished. Two
1) Since we are in switched_from_dl(), new class is not dl_sched_class and
new prio is not less MAX_DL_PRIO. So, the callback returns early; it's
right after !dl_task() check. After that hrtimer_cancel() returns back too.
The above is:
raw_spin_lock(rq->lock); ...
... dl_task_timer()
... raw_spin_lock(rq->lock);
switched_from_dl() ...
hrtimer_try_to_cancel() ...
raw_spin_unlock(rq->lock); ...
hrtimer_cancel() ...
... raw_spin_unlock(rq->lock);
... return HRTIMER_NORESTART;
... ...
raw_spin_lock(rq->lock); ...
2) But the below is also possible:
dl_task_timer()
raw_spin_lock(rq->lock);
...
raw_spin_unlock(rq->lock);
raw_spin_lock(rq->lock); ...
switched_from_dl() ...
hrtimer_try_to_cancel() ...
... return HRTIMER_NORESTART;
raw_spin_unlock(rq->lock); ...
hrtimer_cancel(); ...
raw_spin_lock(rq->lock); ...
In this case hrtimer_cancel() returns immediately. Very unlikely case,
just to mention.
Nobody can manipulate the task, because check_class_changed() is
always called with pi_lock locked. Nobody can force the task to
participate in (concurrent) priority inheritance schemes (the same reason).
All concurrent task operations require pi_lock, which is held by us.
No deadlocks with dl_task_timer() are possible, because it returns
right after !dl_task() check (it does nothing).
If we receive a new dl_task during the time of unlocked rq, we just
don't have to do pull_dl_task() in switched_from_dl() further.
Signed-off-by: Kirill Tkhai <[email protected]>
[ Added comments]
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/1414420852.19914.186.camel@tkhai
Signed-off-by: Ingo Molnar <[email protected]>
|
|
In some cases this can trigger a true flood of output.
Requested-by: Ingo Molnar <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
|
|
The kauditd_thread wait loop is a bit iffy; it has a number of problems:
- calls try_to_freeze() before schedule(); you typically want the
thread to re-evaluate the sleep condition when unfreezing, also
freeze_task() issues a wakeup.
- it unconditionally does the {add,remove}_wait_queue(), even when the
sleep condition is false.
Use wait_event_freezable() that does the right thing.
Reported-by: Mike Galbraith <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Eric Paris <[email protected]>
Cc: [email protected]
Cc: Eric Paris <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
There is a race between kthread_stop() and the new wait_woken() that
can result in a lack of progress.
CPU 0 | CPU 1
|
rfcomm_run() | kthread_stop()
... |
if (!test_bit(KTHREAD_SHOULD_STOP)) |
| set_bit(KTHREAD_SHOULD_STOP)
| wake_up_process()
wait_woken() | wait_for_completion()
set_current_state(INTERRUPTIBLE) |
if (!WQ_FLAG_WOKEN) |
schedule_timeout() |
|
After which both tasks will wait.. forever.
Fix this by having wait_woken() check for kthread_should_stop() but
only for kthreads (obviously).
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Peter Hurley <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
|
|
sched_move_task() is the only interface to change sched_task_group:
cpu_cgrp_subsys methods and autogroup_move_group() use it.
Everything is synchronized by task_rq_lock(), so cpu_cgroup_attach()
is ordered with other users of sched_move_task(). This means we do no
need RCU here: if we've dereferenced a tg here, the .attach method
hasn't been called for it yet.
Thus, we should pass "true" to task_css_check() to silence lockdep
warnings.
Fixes: eeb61e53ea19 ("sched: Fix race between task_group and sched_task_group")
Reported-by: Oleg Nesterov <[email protected]>
Reported-by: Fengguang Wu <[email protected]>
Signed-off-by: Kirill Tkhai <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/r/1414473874.8574.2.camel@tkhai
Signed-off-by: Ingo Molnar <[email protected]>
|
|
Commit 38706bc5a29a (rcutorture: Add callback-flood test) vmalloc()ed
a bunch of RCU callbacks, but failed to free them. This commit fixes
that oversight.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
Add early boot self tests for RCU under CONFIG_PROVE_RCU.
Currently the only test is adding a dummy callback which increments a counter
which we then later verify after calling rcu_barrier*().
Signed-off-by: Pranith Kumar <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
|
|
A long string of get_online_cpus() with each followed by a
put_online_cpu() that fails to acquire cpu_hotplug.lock can result in
overflow of the cpu_hotplug.puts_pending counter. Although this is
perhaps improbably, a system with absolutely no CPU-hotplug operations
will have an arbitrarily long time in which this overflow could occur.
This commit therefore adds overflow checks to get_online_cpus() and
try_get_online_cpus().
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The "cpu" argument to rcu_cleanup_after_idle() is always the current
CPU, so drop it. This moves the smp_processor_id() from the caller to
rcu_cleanup_after_idle(), saving argument-passing overhead. Again,
the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The "cpu" argument to rcu_prepare_for_idle() is always the current
CPU, so drop it. This in turn allows two of the uses of "cpu" in
this function to be replaced with a this_cpu_ptr() and the third by
smp_processor_id(), replacing that of the call to rcu_prepare_for_idle().
Again, the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The "cpu" argument to rcu_needs_cpu() is always the current CPU, so drop
it. This in turn allows the "cpu" argument to rcu_cpu_has_callbacks()
to be removed, which allows the uses of "cpu" in both functions to be
replaced with a this_cpu_ptr(). Again, the anticipated cross-CPU uses
of these functions has been replaced by NO_HZ_FULL.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The "cpu" argument to rcu_note_context_switch() is always the current
CPU, so drop it. This in turn allows the "cpu" argument to
rcu_preempt_note_context_switch() to be removed, which allows the sole
use of "cpu" in both functions to be replaced with a this_cpu_ptr().
Again, the anticipated cross-CPU uses of these functions has been
replaced by NO_HZ_FULL.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
Because rcu_preempt_check_callbacks()'s argument is guaranteed to
always be the current CPU, drop the argument and replace per_cpu()
with __this_cpu_read().
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
Because rcu_pending()'s argument is guaranteed to always be the current
CPU, drop the argument and replace per_cpu_ptr() with this_cpu_ptr().
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The "cpu" argument was kept around on the off-chance that RCU might
offload scheduler-clock interrupts. However, this offload approach
has been replaced by NO_HZ_FULL, which offloads -all- RCU processing
from qualifying CPUs. It is therefore time to remove the "cpu" argument
to rcu_check_callbacks(), which this commit does.
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
The rcu_data per-CPU variable has a number of fields that are atomically
manipulated, potentially by any CPU. This situation can result in false
sharing with per-CPU variables that have the misfortune of being allocated
adjacent to rcu_data in memory. This commit therefore changes the
DEFINE_PER_CPU() to DEFINE_PER_CPU_SHARED_ALIGNED() in order to avoid
this false sharing.
Reported-by: Christoph Lameter <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Christoph Lameter <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
this_cpu_ptr(&rcu_dynticks)
For some functions in kernel/rcu/tree* the rdtp parameter is always
this_cpu_ptr(rdtp). Remove the parameter if constant and calculate the
pointer in function.
This will have the advantage that it is obvious that the address are
all per cpu offsets and thus it will enable the use of this_cpu_ops in
the future.
Signed-off-by: Christoph Lameter <[email protected]>
[ paulmck: Forward-ported to rcu/dev, whitespace adjustment. ]
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Pranith Kumar <[email protected]>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
"These are fixes received after my previous pull request plus one that
has been in the works for quite a while, but its previous version
caused problems to happen, so it's been deferred till now.
Fixed are two recent regressions (MFD enumeration and cpufreq-dt),
ACPI EC regression introduced in 3.17, system suspend error code path
regression introduced in 3.15, an older bug related to recovery from
failing resume from hibernation and a cpufreq-dt driver issue related
to operation performance points.
Specifics:
- Fix a crash on r8a7791/koelsch during resume from system suspend
caused by a recent cpufreq-dt commit (Geert Uytterhoeven).
- Fix an MFD enumeration problem introduced by a recent commit adding
ACPI support to the MFD subsystem that exposed a weakness in the
ACPI core causing ACPI enumeration to be applied to all devices
associated with one ACPI companion object, although it should be
used for one of them only (Mika Westerberg).
- Fix an ACPI EC regression introduced during the 3.17 cycle causing
some Samsung laptops to misbehave as a result of a workaround
targeted at some Acer machines. That includes a revert of a commit
that went too far and a quirk for the Acer machines in question.
From Lv Zheng.
- Fix a regression in the system suspend error code path introduced
during the 3.15 cycle that causes it to fail to take errors from
asychronous execution of "late" suspend callbacks into account
(Imre Deak).
- Fix a long-standing bug in the hibernation resume error code path
that fails to roll back everything correcty on "freeze" callback
errors and leaves some devices in a "suspended" state causing more
breakage to happen subsequently (Imre Deak).
- Make the cpufreq-dt driver disable operation performance points
that are not supported by the VR connected to the CPU voltage plane
with acceptable tolerance instead of constantly failing voltage
scaling later on (Lucas Stach)"
* tag 'pm+acpi-3.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.
Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC"
cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)
PM / Sleep: fix recovery during resuming from hibernation
PM / Sleep: fix async suspend_late/freeze_late error handling
ACPI: Use ACPI companion to match only the first physical device
cpufreq: cpufreq-dt: disable unsupported OPPs
|
|
Pull networking fixes from David Miller:
"A bit has accumulated, but it's been a week or so since my last batch
of post-merge-window fixes, so...
1) Missing module license in netfilter reject module, from Pablo.
Lots of people ran into this.
2) Off by one in mac80211 baserate calculation, from Karl Beldan.
3) Fix incorrect return value from ax88179_178a driver's set_mac_addr
op, which broke use of it with bonding. From Ian Morgan.
4) Checking of skb_gso_segment()'s return value was not all
encompassing, it can return an SKB pointer, a pointer error, or
NULL. Fix from Florian Westphal.
This is crummy, and longer term will be fixed to just return error
pointers or a real SKB.
6) Encapsulation offloads not being handled by
skb_gso_transport_seglen(). From Florian Westphal.
7) Fix deadlock in TIPC stack, from Ying Xue.
8) Fix performance regression from using rhashtable for netlink
sockets. The problem was the synchronize_net() invoked for every
socket destroy. From Thomas Graf.
9) Fix bug in eBPF verifier, and remove the strong dependency of BPF
on NET. From Alexei Starovoitov.
10) In qdisc_create(), use the correct interface to allocate
->cpu_bstats, otherwise the u64_stats_sync member isn't
initialized properly. From Sabrina Dubroca.
11) Off by one in ip_set_nfnl_get_byindex(), from Dan Carpenter.
12) nf_tables_newchain() was erroneously expecting error pointers from
netdev_alloc_pcpu_stats(). It only returna a valid pointer or
NULL. From Sabrina Dubroca.
13) Fix use-after-free in _decode_session6(), from Li RongQing.
14) When we set the TX flow hash on a socket, we mistakenly do so
before we've nailed down the final source port. Move the setting
deeper to fix this. From Sathya Perla.
15) NAPI budget accounting in amd-xgbe driver was counting descriptors
instead of full packets, fix from Thomas Lendacky.
16) Fix total_data_buflen calculation in hyperv driver, from Haiyang
Zhang.
17) Fix bcma driver build with OF_ADDRESS disabled, from Hauke
Mehrtens.
18) Fix mis-use of per-cpu memory in TCP md5 code. The problem is
that something that ends up being vmalloc memory can't be passed
to the crypto hash routines via scatter-gather lists. From Eric
Dumazet.
19) Fix regression in promiscuous mode enabling in cdc-ether, from
Olivier Blin.
20) Bucket eviction and frag entry killing can race with eachother,
causing an unlink of the object from the wrong list. Fix from
Nikolay Aleksandrov.
21) Missing initialization of spinlock in cxgb4 driver, from Anish
Bhatt.
22) Do not cache ipv4 routing failures, otherwise if the sysctl for
forwarding is subsequently enabled this won't be seen. From
Nicolas Cavallari"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (131 commits)
drivers: net: cpsw: Support ALLMULTI and fix IFF_PROMISC in switch mode
drivers: net: cpsw: Fix broken loop condition in switch mode
net: ethtool: Return -EOPNOTSUPP if user space tries to read EEPROM with lengh 0
stmmac: pci: set default of the filter bins
net: smc91x: Fix gpios for device tree based booting
mpls: Allow mpls_gso to be built as module
mpls: Fix mpls_gso handler.
r8152: stop submitting intr for -EPROTO
netfilter: nft_reject_bridge: restrict reject to prerouting and input
netfilter: nft_reject_bridge: don't use IP stack to reject traffic
netfilter: nf_reject_ipv6: split nf_send_reset6() in smaller functions
netfilter: nf_reject_ipv4: split nf_send_reset() in smaller functions
netfilter: nf_tables_bridge: update hook_mask to allow {pre,post}routing
drivers/net: macvtap and tun depend on INET
drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets
drivers/net: Disable UFO through virtio
net: skb_fclone_busy() needs to detect orphaned skb
gre: Use inner mac length when computing tunnel length
mlx4: Avoid leaking steering rules on flow creation error flow
net/mlx4_en: Don't attempt to TX offload the outer UDP checksum for VXLAN
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Various scheduler fixes all over the place: three SCHED_DL fixes,
three sched/numa fixes, two generic race fixes and a comment fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/dl: Fix preemption checks
sched: Update comments for CLONE_NEWNS
sched: stop the unbound recursion in preempt_schedule_context()
sched/fair: Fix division by zero sysctl_numa_balancing_scan_size
sched/fair: Care divide error in update_task_scan_period()
sched/numa: Fix unsafe get_task_struct() in task_numa_assign()
sched/deadline: Fix races between rt_mutex_setprio() and dl_task_timer()
sched/deadline: Don't replenish from a !SCHED_DEADLINE entity
sched: Fix race between task_group and sched_task_group
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus on the kernel side:
- a revert for a newly introduced PMU driver which isn't complete yet
and where we ran out of time with fixes (to be tried again in
v3.19) - this makes up for a large chunk of the diffstat.
- compilation warning fixes
- a printk message fix
- event_idx usage fixes/cleanups"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Trivial typo fix for --demangle
perf tools: Fix report -F dso_from for data without branch info
perf tools: Fix report -F dso_to for data without branch info
perf tools: Fix report -F symbol_from for data without branch info
perf tools: Fix report -F symbol_to for data without branch info
perf tools: Fix report -F mispredict for data without branch info
perf tools: Fix report -F in_tx for data without branch info
perf tools: Fix report -F abort for data without branch info
perf tools: Make CPUINFO_PROC an array to support different kernel versions
perf callchain: Use global caching provided by libunwind
perf/x86/intel: Revert incomplete and undocumented Broadwell client support
perf/x86: Fix compile warnings for intel_uncore
perf: Fix typos in sample code in the perf_event.h header
perf: Fix and clean up initialization of pmu::event_idx
perf: Fix bogus kernel printk
perf diff: Add missing hists__init() call at tool start
|