The result of the division of new_rate by gt_target_rate can be zero (if
new_rate is smaller than gt_target_rate). Using that result as divisor
without checking can result in a division by zero error. Guard against
this by checking for a zero value earlier.
While here, also change the psv variable to an unsigned long to make
sure we don't overflow the datatype as all other types involved are also
unsiged long.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20240225151336.2728533-3-martin.blumenstingl@googlemail.com
All warnings (new ones prefixed by >>):
drivers/clocksource/timer-imx-gpt.c: In function 'mxc_timer_interrupt':
>> drivers/clocksource/timer-imx-gpt.c:279:18: warning: variable 'tstat' set but not used [-Wunused-but-set-variable]
279 | uint32_t tstat;
| ^~~~~
vim +/tstat +279 drivers/clocksource/timer-imx-gpt.c
The change remove the tstats assignment but not the reading of the
register, assuming the register may be a ROR (Reset On Read) which
happens in the driver's interrupt registers.
Fixes: df181e3828 ("clocksource/drivers/imx-gpt: Add support for ARM64")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312231803.XzPddRa5-lkp@intel.com/
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20231227143546.2823683-1-daniel.lezcano@linaro.org
When offlining and onlining CPUs the overall reported idle and iowait
times as reported by /proc/stat jump backward and forward:
cpu 132 0 176 225249 47 6 6 21 0 0
cpu0 80 0 115 112575 33 3 4 18 0 0
cpu1 52 0 60 112673 13 3 1 2 0 0
cpu 133 0 177 226681 47 6 6 21 0 0
cpu0 80 0 116 113387 33 3 4 18 0 0
cpu 133 0 178 114431 33 6 6 21 0 0 <---- jump backward
cpu0 80 0 116 114247 33 3 4 18 0 0
cpu1 52 0 61 183 0 3 1 2 0 0 <---- idle + iowait start with 0
cpu 133 0 178 228956 47 6 6 21 0 0 <---- jump forward
cpu0 81 0 117 114929 33 3 4 18 0 0
Reason for this is that get_idle_time() in fs/proc/stat.c has different
sources for both values depending on if a CPU is online or offline:
- if a CPU is online the values may be taken from its per cpu
tick_cpu_sched structure
- if a CPU is offline the values are taken from its per cpu cpustat
structure
The problem is that the per cpu tick_cpu_sched structure is set to zero on
CPU offline. See tick_cancel_sched_timer() in kernel/time/tick-sched.c.
Therefore when a CPU is brought offline and online afterwards both its idle
and iowait sleeptime will be zero, causing a jump backward in total system
idle and iowait sleeptime. In a similar way if a CPU is then brought
offline again the total idle and iowait sleeptimes will jump forward.
It looks like this behavior was introduced with commit 4b0c0f294f
("tick: Cleanup NOHZ per cpu data on cpu down").
This was only noticed now on s390, since we switched to generic idle time
reporting with commit be76ea6144 ("s390/idle: remove arch_cpu_idle_time()
and corresponding code").
Fix this by preserving the values of idle_sleeptime and iowait_sleeptime
members of the per-cpu tick_sched structure on CPU hotplug.
Fixes: 4b0c0f294f ("tick: Cleanup NOHZ per cpu data on cpu down")
Reported-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240115163555.1004144-1-hca@linux.ibm.com
Pull clockevent/clocksource updates from Daniel Lezcano:
- Fixed error handling at probe time and uninitialized return code on
ep93xx (Arnd Bergman)
- Fixed some kerneldoc warning on Cadence TTC (Randy Dunlap)
- Fixed kerneldoc warning on Timer TI DM (Tony Lindgren)
- Handle interrupt disabling when shutting down the timer on RISC-V
timer (Joshua Yeong)
- Add compatible string for the StarFive JH8100 clint (Sia Jee Heng)
- Separate mtime and mtimecmp registers in DT bindings (Inochi Amaoto)
Link: https://lore.kernel.org/lkml/0f07af92-e4b2-48de-88a6-dd9aa9e49743@linaro.org
When the interrupt property fails to be parsed, ep93xx_timer_of_init()
return code ends up uninitialized:
drivers/clocksource/timer-ep93xx.c:160:6: error: variable 'ret' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (irq < 0) {
^~~~~~~
drivers/clocksource/timer-ep93xx.c:188:9: note: uninitialized use occurs here
return ret;
^~~
drivers/clocksource/timer-ep93xx.c:160:2: note: remove the 'if' if its condition is always false
if (irq < 0) {
^~~~~~~~~~~~~~
Simplify this portion to use the normal construct of just checking
whether a valid interrupt was returned. Note that irq_of_parse_and_map()
never returns a negative value and no other callers check for that either.
Fixes: c28ca80ba3 ("clocksource: ep93xx: Add driver for Cirrus Logic EP93xx")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20231212214616.193098-1-arnd@kernel.org
Fix some function kernel-doc warnings to placate scripts/kernel-doc.
timer-cadence-ttc.c:79: warning: Function parameter or member 'clk_rate_change_nb' not described in 'ttc_timer'
timer-cadence-ttc.c:158: warning: Function parameter or member 'cs' not described in '__ttc_clocksource_read'
timer-cadence-ttc.c:194: warning: expecting prototype for ttc_set_{shutdown|oneshot|periodic}(). Prototype was for ttc_shutdown() instead
timer-cadence-ttc.c:196: warning: No description found for return value of 'ttc_shutdown'
timer-cadence-ttc.c:212: warning: No description found for return value of 'ttc_set_periodic'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Michal Simek <michal.simek@amd.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Michal Simek <michal.simek@amd.com>
Tested-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20231205230448.772-1-rdunlap@infradead.org
When no timer is queued into an empty timer base, the next_expiry will not
be updated. It was originally calculated as
base->clk + NEXT_TIMER_MAX_DELTA
When the timer base stays empty long enough (> NEXT_TIMER_MAX_DELTA), the
next_expiry value of the empty base suggests that there is a timer pending
soon. This might be more a kind of a theoretical problem, but the fix
doesn't hurt.
Use only base->next_expiry value as nextevt when timers are
pending. Otherwise nextevt will be jiffies + NEXT_TIMER_MAX_DELTA. As all
information is in place, update base->next_expiry value of the empty timer
base as well.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-13-anna-maria@linutronix.de
To improve readability of the code, split base->idle calculation and
expires calculation into separate parts. While at it, update the comment
about timer base idle marking.
Thereby the following subtle change happens if the next event is just one
jiffy ahead and the tick was already stopped: Originally base->is_idle
remains true in this situation. Now base->is_idle turns to false. This may
spare an IPI if a timer is enqueued remotely to an idle CPU that is going
to tick on the next jiffy.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-12-anna-maria@linutronix.de
Forwarding timer base is done when the next expiry value is calculated and
when a new timer is enqueued. When the next expiry value is calculated the
jiffies value is already available and does not need to be reread a second
time.
Splitting out the forward timer base functionality to make it executable
via both contextes - those where jiffies are already known and those, where
jiffies need to be read.
No functional change.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-10-anna-maria@linutronix.de
The current check whether a forward of the timer base is required can be
simplified by using an already existing comparison function which is easier
to read. The related comment is outdated and was not updated when the check
changed in commit 36cd28a4cd ("timers: Lower base clock forwarding
threshold").
Use time_before_eq() for the check and replace the comment by copying the
comment from the same check inside get_next_timer_interrupt(). Move the
precious information of the outdated comment to the proper place in
__run_timers().
No functional change.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-9-anna-maria@linutronix.de
Deferrable timers do not prevent CPU from going idle and are not taken into
account on idle path. Sending an IPI to a remote CPU when a new first
deferrable timer was enqueued will wake up the remote CPU but nothing will
be done regarding the deferrable timers.
Drop IPI completely when a new first deferrable timer was enqueued.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-7-anna-maria@linutronix.de
For starting a timer, the timer is enqueued into a bucket of the timer
wheel. The bucket expiry is the defacto expiry of the timer but it is not
equal the timer expiry because of increasing granularity when bucket is in
a higher level of the wheel. To be able to figure out in a trace whether a
timer expired in time or not, the bucket expiry time is required as well.
Add bucket expiry time to the timer_start tracepoint and thereby simplify
the arguments.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-5-anna-maria@linutronix.de
When the next tick is in the past, the delta between basemono and the next
tick gets negativ. But the next tick should never be in the past. The
negative effect of a wrong next tick might be a stop of the tick and timers
might expire late.
To prevent expensive debugging when changing underlying code, add a
WARN_ON_ONCE into this code path. To prevent complete misbehaviour, also
reset next_tick to basemono in this case.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-4-anna-maria@linutronix.de
tick_nohz_stop_tick() contains the expires (u64 variable) and tick
(ktime_t) variable. In the beginning the value of expires is written to
tick. Afterwards none of the variables is changed. They are only used for
checks.
Drop the not required variable tick and use always expires instead.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20231201092654.34614-3-anna-maria@linutronix.de
This function is defined globally in clocksource.c and used conditionally
in clockevent.c, which the declaration hidden when clockevent support
is disabled. This causes a harmless warning in the definition:
kernel/time/clocksource.c:1324:9: warning: no previous prototype for 'sysfs_get_uname' [-Wmissing-prototypes]
1324 | ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt)
Move the declaration out of the #ifdef so it is always visible.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231108125843.3806765-5-arnd@kernel.org
Pull Kbuild fixes from Masahiro Yamada:
- Fix section mismatch warning messages for riscv and loongarch
- Remove CONFIG_IA64 left-over from linux/export-internal.h
- Fix the location of the quotes for UIMAGE_NAME
- Fix a memory leak bug in Kconfig
* tag 'kbuild-fixes-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: fix memory leak from range properties
kbuild: Move the single quotes for image name
linux/export: clean up the IA-64 KSYM_FUNC macro
modpost: fix section mismatch message for RELA
Pull irq fix from Borislav Petkov:
- Flush the translation service tables to prevent unpredictable
behavior on non-coherent GIC devices
* tag 'irq_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3-its: Flush ITS tables correctly in non-coherent GIC designs
Pull x86 fixes from Borislav Petkov:
- Ignore invalid x2APIC entries in order to not waste per-CPU data
- Fix a back-to-back signals handling scenario when shadow stack is in
use
- A documentation fix
- Add Kirill as TDX maintainer
* tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/acpi: Ignore invalid x2APIC entries
x86/shstk: Delay signal entry SSP write until after user accesses
x86/Documentation: Indent 'note::' directive for protocol version number note
MAINTAINERS: Add Intel TDX entry
Pull timer fix from Borislav Petkov:
- Do the push of pending hrtimers away from a CPU which is being
offlined earlier in the offlining process in order to prevent a
deadlock
* tag 'timers_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimers: Push pending hrtimers away from outgoing CPU earlier
Pull scheduler fixes from Borislav Petkov:
- Fix virtual runtime calculation when recomputing a sched entity's
weights
- Fix wrongly rejected unprivileged poll requests to the cgroup psi
pressure files
- Make sure the load balancing is done by only one CPU
* tag 'sched_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix the decision for load balance
sched: psi: fix unprivileged polling against cgroups
sched/eevdf: Fix vruntime adjustment on reweight
Pull locking fix from Borislav Petkov:
- Fix a hardcoded futex flags case which lead to one robust futex test
failure
* tag 'locking_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Fix hardcoded flags
Pull perf fix from Borislav Petkov:
- Make sure the context refcount is transferred too when migrating perf
events
* tag 'perf_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix cpuctx refcounting
Pull SCSI fixes from James Bottomley:
"Seven small fixes, six in drivers and one in sd.
The sd fix is so large because it changes a struct pointer to a struct
but otherwise is fairly simple"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: qcom-ufs: dt-bindings: Document the SM8650 UFS Controller
scsi: sd: Fix sshdr use in sd_suspend_common()
scsi: scsi_debug: Delete some bogus error checking
scsi: scsi_debug: Fix some bugs in sdebug_error_write()
scsi: ufs: core: Fix racing issue between ufshcd_mcq_abort() and ISR
scsi: ufs: core: Expand MCQ queue slot to DeviceQueueDepth + 1
scsi: qla2xxx: Fix system crash due to bad pointer access
Pull parisc fixes from Helge Deller:
"On parisc we still sometimes need writeable stacks, e.g. if programs
aren't compiled with gcc-14. To avoid issues with the upcoming
systemd-254 we therefore have to disable prctl(PR_SET_MDWE) for now
(for parisc only).
The other two patches are minor: a bugfix for the soft power-off on
qemu with 64-bit kernel and prefer strscpy() over strlcpy():
- Fix power soft-off on qemu
- Disable prctl(PR_SET_MDWE) since parisc sometimes still needs
writeable stacks
- Use strscpy instead of strlcpy in show_cpuinfo()"
* tag 'parisc-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
prctl: Disable prctl(PR_SET_MDWE) on parisc
parisc/power: Fix power soft-off when running on qemu
parisc: Replace strlcpy() with strscpy()
Pull xfs fixes from Chandan Babu:
- Fix deadlock arising due to intent items in AIL not being cleared
when log recovery fails
- Fix stale data exposure bug when remapping COW fork extents to data
fork
- Fix deadlock when data device flush fails
- Fix AGFL minimum size calculation
- Select DEBUG_FS instead of XFS_DEBUG when XFS_ONLINE_SCRUB_STATS is
selected
- Fix corruption of log inode's extent count field when NREXT64 feature
is enabled
* tag 'xfs-6.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: recovery should not clear di_flushiter unconditionally
xfs: inode recovery does not validate the recovered inode
xfs: fix again select in kconfig XFS_ONLINE_SCRUB_STATS
xfs: fix internal error from AGFL exhaustion
xfs: up(ic_sema) if flushing data device fails
xfs: only remap the written blocks in xfs_reflink_end_cow_extent
XFS: Update MAINTAINERS to catch all XFS documentation
xfs: abort intent items when recovery intents fail
xfs: factor out xfs_defer_pending_abort
Pull nfsd fixes from Chuck Lever:
- Fix several long-standing bugs in the duplicate reply cache
- Fix a memory leak
* tag 'nfsd-6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
NFSD: Fix checksum mismatches in the duplicate reply cache
NFSD: Fix "start of NFS reply" pointer passed to nfsd_cache_update()
NFSD: Update nfsd_cache_append() to use xdr_stream
nfsd: fix file memleak on client_opens_release
Pull smb client fixes from Steve French:
- multichannel fixes (including a lock ordering fix and an important
refcounting fix)
- spnego fix
* tag '6.7-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: fix lock ordering while disabling multichannel
cifs: fix leak of iface for primary channel
cifs: fix check of rc in function generate_smb3signingkey
cifs: spnego: add ';' in HOST_KEY_LEN
