$ perf record -h -I
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-I, --intr-regs[=<any register>]
sample selected machine registers on interrupt, use -I ? to list register names
$ m
$ perf record -I ?
Workload failed: No such file or directory
$
After:
$ perf record -h -I
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-I, --intr-regs[=<any register>]
sample selected machine registers on interrupt, use '-I?' to list register names
$
$ perf record -I?
available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11 R12 R13 R14 R15
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-I, --intr-regs[=<any register>]
sample selected machine registers on interrupt, use '-I?' to list register names
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: bcc84ec65a ("perf record: Add ability to name registers to record")
Link: https://lkml.kernel.org/n/tip-r0xhfhy5radmkhhcbcfs5izf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When running 'make -C tools clean' I noticed that a revision controlled
file was being deleted:
$ git diff
diff --git a/tools/pci/pcitest.sh b/tools/pci/pcitest.sh
deleted file mode 100644
index 75ed48ff2990..000000000000
--- a/tools/pci/pcitest.sh
+++ /dev/null
@@ -1,72 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-
-echo "BAR tests"
-echo
<SNIP>
So I changed the make variables to fix that, testing it should produce
the same intended result while not deleting revision controlled files.
$ make O=/tmp/build/pci -C tools/pci install
make: Entering directory '/home/acme/git/perf/tools/pci'
make -f /home/acme/git/perf/tools/build/Makefile.build dir=. obj=pcitest
install -d -m 755 /usr/bin; \
for program in /tmp/build/pci/pcitest pcitest.sh; do \
install $program /usr/bin; \
done
install: cannot change permissions of ‘/usr/bin’: Operation not permitted
install: cannot create regular file '/usr/bin/pcitest': Permission denied
install: cannot create regular file '/usr/bin/pcitest.sh': Permission denied
make: *** [Makefile:46: install] Error 1
make: Leaving directory '/home/acme/git/perf/tools/pci'
$ ls -la /tmp/build/pci/pcitest
-rwxrwxr-x. 1 acme acme 27152 May 13 13:52 /tmp/build/pci/pcitest
$ /tmp/build/pci/pcitest
can't open PCI Endpoint Test device: No such file or directory
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 1ce78ce094 ("tools: PCI: Change pcitest compiling process")
Link: https://lkml.kernel.org/n/tip-9re6bd7eh9epi3koslkv3ocn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get the changes in:
878068ea27 ("perf/x86: Support outputting XMM registers")
That will be used in a followup patch to allow users to ask for some or
all of those registers to be collected in certain contatexts.
This silences the following perf build warning:
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/perf_regs.h' differs from latest version at 'arch/x86/include/uapi/asm/perf_regs.h'
diff -u tools/arch/x86/include/uapi/asm/perf_regs.h arch/x86/include/uapi/asm/perf_regs.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-6pjnnrzqt3x3n2cd6br3wk7k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get the changes in:
59073aaf6d ("kvm: x86: Add exception payload fields to kvm_vcpu_events")
This silences the following perf build warning:
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/kvm.h' differs from latest version at 'arch/x86/include/uapi/asm/kvm.h'
diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
The changes in this file are in something not used at this time in any
tools/perf/ tool.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lkml.kernel.org/n/tip-6uh8tpraons0h22dmxgfyony@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To bring in the change made in this cset:
b69656fa7e ("x86/uaccess: Fix up the fixup")
Silencing this perf build warning:
Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
No changes in the tooling using this, that was just to ease some objtool
return checking.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-j0mxgqkuibhw5qid9saaspdu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When compiled with libunwind, perf does some preparatory work when
processing side-band events. This is not needed when report actually
don't unwind dwarf callchains, so it's disabled with
dwarf_callchain_users bool.
However we could move that check to higher level and shield more
unwanted code for normal report processing, giving us following speed up
on kernel build profile:
Before:
$ perf record make -j40
...
$ ll ../../perf.data
-rw-------. 1 jolsa jolsa 461783932 Apr 26 09:11 perf.data
$ perf stat -e cycles:u,instructions:u perf report -i perf.data > out
Performance counter stats for 'perf report -i perf.data':
78,669,920,155 cycles:u
99,076,431,951 instructions:u # 1.26 insn per cycle
55.382823668 seconds time elapsed
27.512341000 seconds user
27.712871000 seconds sys
After:
$ perf stat -e cycles:u,instructions:u perf report -i perf.data > out
Performance counter stats for 'perf report -i perf.data':
59,626,798,904 cycles:u
88,583,575,849 instructions:u # 1.49 insn per cycle
21.296935559 seconds time elapsed
20.010191000 seconds user
1.202935000 seconds sys
The speed is higher with profile having many side-band events,
because these trigger libunwind preparatory code.
This does not apply for perf compiled with libdw for dwarf unwind,
only for build with libunwind.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190426073804.17238-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Install directories of header and library files are hard coded in
pkg-config template file.
They must be configurable, the Makefile should set them on the
compilation / install stage.
Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190418211556.5a12adc3@oasis.local.home
Link: http://lkml.kernel.org/r/20190329144546.5819-1-tstoyanov@vmware.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch add support for DWARF register mappings and libdw registers
initialization, which is used by perf callchain analyzing when
--call-graph=dwarf is given.
Here is the elfutils csky backend patch set:
https://sourceware.org/ml/elfutils-devel/2019-q2/msg00007.html
Signed-off-by: Mao Han <han_mao@c-sky.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1555860794-10572-1-git-send-email-guoren@kernel.org
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are a couple of spelling mistakes in test assert messages. Fix them.
Signed-off-by: Colin King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20190417105539.5902-1-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hist__account_cycles() function is executed when the
hist_iter__branch_callback() is called.
But it looks it's not necessary. In hist__account_cycles, it already
walks on all branch entries.
This patch moves the hist__account_cycles out of callback, now the data
processing is much faster than before.
Previous code has an issue that the ch[offset].num++ (in
__symbol__account_cycles) is executed repeatedly since
hist__account_cycles is called in each hist_iter__branch_callback, so
the counting of ch[offset].num is not correct (too big).
With this patch, the issue is fixed. And we don't need the code of
"ch->reset >= ch->num / 2" to check if there are too many overlaps (in
annotation__count_and_fill), otherwise some data would be hidden.
Now, we can try, for example:
perf record -b ...
perf annotate or perf report -s symbol
The before/after output should be no change.
v3:
---
Fix the crash in stdio mode.
Like previous code, it needs the checking of ui__has_annotation()
before hist__account_cycles()
v2:
---
1. Cover the similar perf report
2. Remove the checking code "ch->reset >= ch->num / 2"
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1552684577-29041-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add wait_var_event_interruptible() to allow interruptible waits for events.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Allow used DNS resolver keys to be invalidated after use if the caller is
doing its own caching of the results. This reduces the amount of resources
required.
Fix AFS to invalidate DNS results to kill off permanent failure records
that get lodged in the resolver keyring and prevent future lookups from
happening.
Fixes: 0a5143f2f8 ("afs: Implement VL server rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix it such that afs_cell records always have a VL server list record
attached, even if it's a dummy one, so that various checks can be removed.
Signed-off-by: David Howells <dhowells@redhat.com>
When afs_update_cell() replaces the cell->vl_servers list, it uses RCU
protocol so that proc is protected, but doesn't take ->vl_servers_lock to
protect afs_start_vl_iteration() (which does actually take a shared lock).
Fix this by making afs_update_cell() take an exclusive lock when replacing
->vl_servers.
Fixes: 0a5143f2f8 ("afs: Implement VL server rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
afs_xattr_get_yfs() tries to free yacl, which may hold an error value (say
if yfs_fs_fetch_opaque_acl() failed and returned an error).
Fix this by allocating yacl up front (since it's a fixed-length struct,
unlike afs_acl) and passing it in to the RPC function. This also allows
the flags to be placed in the object rather than passing them through to
the RPC function.
Fixes: ae46578b96 ("afs: Get YFS ACLs and information through xattrs")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix incorrect error handling in afs_xattr_get_acl() where there appears to
be a redundant assignment before return, but in fact the return should be a
goto to the error handling at the end of the function.
Fixes: 260f082bae ("afs: Get an AFS3 ACL as an xattr")
Addresses-Coverity: ("Unused Value")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Joe Perches <joe@perches.com>
- error out if a user specifies a directory instead of a file from
"Save" menu of GUI interfaces
- do not overwrite .config if there is no change in the configuration
- create parent directories as needed when a user specifies a new file
path from "Save" menu of menuconfig/nconfig
- fix potential buffer overflow
- some trivial cleanups
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Merge tag 'kconfig-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kconfig updates from Masahiro Yamada:
- error out if a user specifies a directory instead of a file from
"Save" menu of GUI interfaces
- do not overwrite .config if there is no change in the configuration
- create parent directories as needed when a user specifies a new file
path from "Save" menu of menuconfig/nconfig
- fix potential buffer overflow
- some trivial cleanups
* tag 'kconfig-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: make conf_get_autoconfig_name() static
kconfig: use snprintf for formatting pathnames
kconfig: remove useless NULL pointer check in conf_write_dep()
kconfig: make parent directories for the saved .config as needed
kconfig: do not write .config if the content is the same
kconfig: do not accept a directory for configuration output
kconfig: remove trailing whitespaces
kconfig: Make nconf-cfg.sh executable
- Update the ACPICA code in the kernel to upstream revision 20190509
including one regression fix:
* Prevent excessive ACPI debug messages from being printed
by moving the ACPI_DEBUG_DEFAULT definition to the right
place (Erik Schmauss).
- Set the enable_for_wake bits for wakeup GPEs during suspend to
idle to allow acpi_enable_all_wakeup_gpes() to enable them as
aproppriate and make wakeup devices sighaling events through ACPI
GPEs work with suspend-to-idle again (Rajat Jain).
- Use 64 bits to store the return values of _ADR which are assumed
to be 64-bit by some bus specs and may contain nonzero bits in the
upper 32 bits part for some devices (Pierre-Louis Bossart).
- Fix two minor issues with the ACPI documentation (Sakari Ailus).
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Merge tag 'acpi-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI updates from Rafael Wysocki:
"These fix two regressions introduced during the 5.0 cycle, in ACPICA
and in device PM, cause the values returned by _ADR to be stored in 64
bits and fix two ACPI documentation issues.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20190509
including one regression fix:
* Prevent excessive ACPI debug messages from being printed by
moving the ACPI_DEBUG_DEFAULT definition to the right place
(Erik Schmauss).
- Set the enable_for_wake bits for wakeup GPEs during suspend to idle
to allow acpi_enable_all_wakeup_gpes() to enable them as
aproppriate and make wakeup devices sighaling events through ACPI
GPEs work with suspend-to-idle again (Rajat Jain).
- Use 64 bits to store the return values of _ADR which are assumed to
be 64-bit by some bus specs and may contain nonzero bits in the
upper 32 bits part for some devices (Pierre-Louis Bossart).
- Fix two minor issues with the ACPI documentation (Sakari Ailus)"
* tag 'acpi-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: Set enable_for_wake for wakeup GPEs during suspend-to-idle
Documentation: ACPI: Direct references are allowed to devices only
Documentation: ACPI: Use tabs for graph ASL indentation
ACPICA: Update version to 20190509
ACPICA: Linux: move ACPI_DEBUG_DEFAULT flag out of ifndef
ACPI: bus: change _ADR representation to 64 bits
- Fix recent regression causing kernels built with CONFIG_PM
unset to crash on systems that support the Performance and
Energy Bias Hint (EPB) by avoiding to compile the EPB-related
code depending on CONFIG_PM when it is unset (Rafael Wysocki).
- Clean up the transition notifier invocation code in the cpufreq
core and change some users of cpufreq transition notifiers
accordingly (Viresh Kumar).
- Change MAINTAINERS to cover the schedutil governor as part of
cpufreq (Viresh Kumar).
- Simplify cpufreq_init_policy() to avoid redundant computations
(Yue Hu).
- Add explanatory comment to the cpufreq core (Rafael Wysocki).
- Introduce a new flag, GENPD_FLAG_RPM_ALWAYS_ON, to the generic
power domains (genpd) framework along with the first user of it
(Leonard Crestez).
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Merge tag 'pm-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These fix a recent regression causing kernels built with CONFIG_PM
unset to crash on systems that support the Performance and Energy Bias
Hint (EPB), clean up the cpufreq core and some users of transition
notifiers and introduce a new power domain flag into the generic power
domains framework (genpd).
Specifics:
- Fix recent regression causing kernels built with CONFIG_PM unset to
crash on systems that support the Performance and Energy Bias Hint
(EPB) by avoiding to compile the EPB-related code depending on
CONFIG_PM when it is unset (Rafael Wysocki).
- Clean up the transition notifier invocation code in the cpufreq
core and change some users of cpufreq transition notifiers
accordingly (Viresh Kumar).
- Change MAINTAINERS to cover the schedutil governor as part of
cpufreq (Viresh Kumar).
- Simplify cpufreq_init_policy() to avoid redundant computations (Yue
Hu).
- Add explanatory comment to the cpufreq core (Rafael Wysocki).
- Introduce a new flag, GENPD_FLAG_RPM_ALWAYS_ON, to the generic
power domains (genpd) framework along with the first user of it
(Leonard Crestez)"
* tag 'pm-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
soc: imx: gpc: Use GENPD_FLAG_RPM_ALWAYS_ON for ERR009619
PM / Domains: Add GENPD_FLAG_RPM_ALWAYS_ON flag
cpufreq: Update MAINTAINERS to include schedutil governor
cpufreq: Don't find governor for setpolicy drivers in cpufreq_init_policy()
cpufreq: Explain the kobject_put() in cpufreq_policy_alloc()
cpufreq: Call transition notifier only once for each policy
x86: intel_epb: Take CONFIG_PM into account
Pull crypto fixes from Herbert Xu:
"This fixes a number of issues in the chelsio and caam drivers"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
Revert "crypto: caam/jr - Remove extra memory barrier during job ring dequeue"
crypto: caam - fix caam_dump_sg that iterates through scatterlist
crypto: caam - fix DKP detection logic
MAINTAINERS: Maintainer for Chelsio crypto driver
crypto: chelsio - count incomplete block in IV
crypto: chelsio - Fix softlockup with heavy I/O
crypto: chelsio - Fix NULL pointer dereference
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch aims to suppress 3 missing-break-in-switch false positives
on some architectures.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix afs_release() to go through the cleanup part of the function if
FMODE_WRITE is set rather than exiting through vfs_fsync() (which skips the
cleanup). The cleanup involves discarding the refs on the key used for
file ops and the writeback key record.
Also fix afs_evict_inode() to clean up any left over wb keys attached to
the inode/vnode when it is removed.
Fixes: 5a81327616 ("afs: Do better accretion of small writes on newly created content")
Signed-off-by: David Howells <dhowells@redhat.com>
media_device_cleanup() and v4l2_m2m_unregister_media_controller() were
missing in the probe error path.
While at it, re-order calls in the remove path to unregister/cleanup
things in the reverse order they were initialized/registered.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
v4l2-compliance complains that ->bus_info is empty.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This makes the function more generic so it can easily be re-used when
adding support for the decoding functionality.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Those calls are needed to restore a clean PM state when the probe fails
or when the driver is unloaded such that future ->probe() calls can
initialize runtime PM again.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Pass -1 to video_register_device() to let the core assign the first
free id instead of trying to get id 0.
In practice it doesn't make a difference since video_register_device()
is not strict about id requests and will anyway pick the first free id
starting at the id passed in argument, and passing -1 has the same
effect as passing 0. But let's comply with the API doc and pass -1
here.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
* pm-cpufreq:
cpufreq: Update MAINTAINERS to include schedutil governor
cpufreq: Don't find governor for setpolicy drivers in cpufreq_init_policy()
cpufreq: Explain the kobject_put() in cpufreq_policy_alloc()
cpufreq: Call transition notifier only once for each policy
* pm-domains:
soc: imx: gpc: Use GENPD_FLAG_RPM_ALWAYS_ON for ERR009619
PM / Domains: Add GENPD_FLAG_RPM_ALWAYS_ON flag
* acpi-bus:
ACPI: bus: change _ADR representation to 64 bits
* acpi-doc:
Documentation: ACPI: Direct references are allowed to devices only
Documentation: ACPI: Use tabs for graph ASL indentation
* acpi-pm:
ACPI: PM: Set enable_for_wake for wakeup GPEs during suspend-to-idle
The directive specified in the documentation to add an exception
for a single file in a Makefile was inverted.
Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/522362a1b934ee39d0af0abb231f68e160ecf1a8.1557874043.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 345c0dbf3a ("ext4: protect journal inode's blocks using
block_validity") failed to add an exception for the journal inode in
ext4_check_blockref(), which is the function used by ext4_get_branch()
for indirect blocks. This caused attempts to read from the ext3-style
journals to fail with:
[ 848.968550] EXT4-fs error (device sdb7): ext4_get_branch:171: inode #8: block 30343695: comm jbd2/sdb7-8: invalid block
Fix this by adding the missing exception check.
Fixes: 345c0dbf3a ("ext4: protect journal inode's blocks using block_validity")
Reported-by: Arthur Marsh <arthur.marsh@internode.on.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This is being sent to get a fix for the gcc 9.1 build warnings, and I've
also pulled in some bug fix patches that were posted in the last two
weeks.
- Avoid the gcc 9.1 warning about overflowing a union member
- Fix the wrong callback type for a single response netlink to doit
- Bug fixes from more usage of the mlx5 devx interface
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull more rdma updates from Jason Gunthorpe:
"This is being sent to get a fix for the gcc 9.1 build warnings, and
I've also pulled in some bug fix patches that were posted in the last
two weeks.
- Avoid the gcc 9.1 warning about overflowing a union member
- Fix the wrong callback type for a single response netlink to doit
- Bug fixes from more usage of the mlx5 devx interface"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
net/mlx5: Set completion EQs as shared resources
IB/mlx5: Verify DEVX general object type correctly
RDMA/core: Change system parameters callback from dumpit to doit
RDMA: Directly cast the sockaddr union to sockaddr
Merge more updates from Andrew Morton:
- a couple of hotfixes
- almost all of the rest of MM
- lib/ updates
- binfmt_elf updates
- autofs updates
- quite a lot of misc fixes and updates
- reiserfs, fatfs
- signals
- exec
- cpumask
- rapidio
- sysctl
- pids
- eventfd
- gcov
- panic
- pps
- gdb script updates
- ipc updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (126 commits)
mm: memcontrol: fix NUMA round-robin reclaim at intermediate level
mm: memcontrol: fix recursive statistics correctness & scalabilty
mm: memcontrol: move stat/event counting functions out-of-line
mm: memcontrol: make cgroup stats and events query API explicitly local
drivers/virt/fsl_hypervisor.c: prevent integer overflow in ioctl
drivers/virt/fsl_hypervisor.c: dereferencing error pointers in ioctl
mm, memcg: rename ambiguously named memory.stat counters and functions
arch: remove <asm/sizes.h> and <asm-generic/sizes.h>
treewide: replace #include <asm/sizes.h> with #include <linux/sizes.h>
fs/block_dev.c: Remove duplicate header
fs/cachefiles/namei.c: remove duplicate header
include/linux/sched/signal.h: replace `tsk' with `task'
fs/coda/psdev.c: remove duplicate header
ipc: do cyclic id allocation for the ipc object.
ipc: conserve sequence numbers in ipcmni_extend mode
ipc: allow boot time extension of IPCMNI from 32k to 16M
ipc/mqueue: optimize msg_get()
ipc/mqueue: remove redundant wq task assignment
ipc: prevent lockup on alloc_msg and free_msg
scripts/gdb: print cached rate in lx-clk-summary
...
When a cgroup is reclaimed on behalf of a configured limit, reclaim
needs to round-robin through all NUMA nodes that hold pages of the memcg
in question. However, when assembling the mask of candidate NUMA nodes,
the code only consults the *local* cgroup LRU counters, not the
recursive counters for the entire subtree. Cgroup limits are frequently
configured against intermediate cgroups that do not have memory on their
own LRUs. In this case, the node mask will always come up empty and
reclaim falls back to scanning only the current node.
If a cgroup subtree has some memory on one node but the processes are
bound to another node afterwards, the limit reclaim will never age or
reclaim that memory anymore.
To fix this, use the recursive LRU counts for a cgroup subtree to
determine which nodes hold memory of that cgroup.
The code has been broken like this forever, so it doesn't seem to be a
problem in practice. I just noticed it while reviewing the way the LRU
counters are used in general.
Link: http://lkml.kernel.org/r/20190412151507.2769-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now, when somebody needs to know the recursive memory statistics
and events of a cgroup subtree, they need to walk the entire subtree and
sum up the counters manually.
There are two issues with this:
1. When a cgroup gets deleted, its stats are lost. The state counters
should all be 0 at that point, of course, but the events are not.
When this happens, the event counters, which are supposed to be
monotonic, can go backwards in the parent cgroups.
2. During regular operation, we always have a certain number of lazily
freed cgroups sitting around that have been deleted, have no tasks,
but have a few cache pages remaining. These groups' statistics do not
change until we eventually hit memory pressure, but somebody
watching, say, memory.stat on an ancestor has to iterate those every
time.
This patch addresses both issues by introducing recursive counters at
each level that are propagated from the write side when stats change.
Upward propagation happens when the per-cpu caches spill over into the
local atomic counter. This is the same thing we do during charge and
uncharge, except that the latter uses atomic RMWs, which are more
expensive; stat changes happen at around the same rate. In a sparse
file test (page faults and reclaim at maximum CPU speed) with 5 cgroup
nesting levels, perf shows __mod_memcg_page state at ~1%.
Link: http://lkml.kernel.org/r/20190412151507.2769-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These are getting too big to be inlined in every callsite. They were
stolen from vmstat.c, which already out-of-lines them, and they have
only been growing since. The callsites aren't that hot, either.
Move __mod_memcg_state()
__mod_lruvec_state() and
__count_memcg_events() out of line and add kerneldoc comments.
Link: http://lkml.kernel.org/r/20190412151507.2769-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: memcontrol: memory.stat cost & correctness".
The cgroup memory.stat file holds recursive statistics for the entire
subtree. The current implementation does this tree walk on-demand
whenever the file is read. This is giving us problems in production.
1. The cost of aggregating the statistics on-demand is high. A lot of
system service cgroups are mostly idle and their stats don't change
between reads, yet we always have to check them. There are also always
some lazily-dying cgroups sitting around that are pinned by a handful
of remaining page cache; the same applies to them.
In an application that periodically monitors memory.stat in our
fleet, we have seen the aggregation consume up to 5% CPU time.
2. When cgroups die and disappear from the cgroup tree, so do their
accumulated vm events. The result is that the event counters at
higher-level cgroups can go backwards and confuse some of our
automation, let alone people looking at the graphs over time.
To address both issues, this patch series changes the stat
implementation to spill counts upwards when the counters change.
The upward spilling is batched using the existing per-cpu cache. In a
sparse file stress test with 5 level cgroup nesting, the additional cost
of the flushing was negligible (a little under 1% of CPU at 100% CPU
utilization, compared to the 5% of reading memory.stat during regular
operation).
This patch (of 4):
memcg_page_state(), lruvec_page_state(), memcg_sum_events() are
currently returning the state of the local memcg or lruvec, not the
recursive state.
In practice there is a demand for both versions, although the callers
that want the recursive counts currently sum them up by hand.
Per default, cgroups are considered recursive entities and generally we
expect more users of the recursive counters, with the local counts being
special cases. To reflect that in the name, add a _local suffix to the
current implementations.
The following patch will re-incarnate these functions with recursive
semantics, but with an O(1) implementation.
[hannes@cmpxchg.org: fix bisection hole]
Link: http://lkml.kernel.org/r/20190417160347.GC23013@cmpxchg.org
Link: http://lkml.kernel.org/r/20190412151507.2769-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The "param.count" value is a u64 thatcomes from the user. The code
later in the function assumes that param.count is at least one and if
it's not then it leads to an Oops when we dereference the ZERO_SIZE_PTR.
Also the addition can have an integer overflow which would lead us to
allocate a smaller "pages" array than required. I can't immediately
tell what the possible run times implications are, but it's safest to
prevent the overflow.
Link: http://lkml.kernel.org/r/20181218082129.GE32567@kadam
Fixes: 6db7199407 ("drivers/virt: introduce Freescale hypervisor management driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Timur Tabi <timur@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strndup_user() returns error pointers on error, and then in the error
handling we pass the error pointers to kfree(). It will cause an Oops.
Link: http://lkml.kernel.org/r/20181218082003.GD32567@kadam
Fixes: 6db7199407 ("drivers/virt: introduce Freescale hypervisor management driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Timur Tabi <timur@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I spent literally an hour trying to work out why an earlier version of
my memory.events aggregation code doesn't work properly, only to find
out I was calling memcg->events instead of memcg->memory_events, which
is fairly confusing.
This naming seems in need of reworking, so make it harder to do the
wrong thing by using vmevents instead of events, which makes it more
clear that these are vm counters rather than memcg-specific counters.
There are also a few other inconsistent names in both the percpu and
aggregated structs, so these are all cleaned up to be more coherent and
easy to understand.
This commit contains code cleanup only: there are no logic changes.
[akpm@linux-foundation.org: fix it for preceding changes]
Link: http://lkml.kernel.org/r/20190208224319.GA23801@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that all instances of #include <asm/sizes.h> have been replaced with
#include <linux/sizes.h>, we can remove these.
Link: http://lkml.kernel.org/r/1553267665-27228-2-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit dccd2304cc ("ARM: 7430/1: sizes.h: move from asm-generic
to <linux/sizes.h>"), <asm/sizes.h> and <asm-generic/sizes.h> are just
wrappers of <linux/sizes.h>.
This commit replaces all <asm/sizes.h> and <asm-generic/sizes.h> to
prepare for the removal.
Link: http://lkml.kernel.org/r/1553267665-27228-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/dax.h is included more than once.
Link: http://lkml.kernel.org/r/5c867e95.1c69fb81.4f15a.e5e4@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/xattr.h is included more than once.
Link: http://lkml.kernel.org/r/5c86803d.1c69fb81.1a7c6.2b78@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file uses "task" 85 times and "tsk" 25 times. It is better to be
consistent.
Link: http://lkml.kernel.org/r/20181129180547.15976-1-avagin@gmail.com
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/poll.h is included more than once.
Link: http://lkml.kernel.org/r/5c86820f.1c69fb81.149f0.0834@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For ipcmni_extend mode, the sequence number space is only 7 bits. So
the chance of id reuse is relatively high compared with the non-extended
mode.
To alleviate this id reuse problem, this patch enables cyclic allocation
for the index to the radix tree (idx). The disadvantage is that this
can cause a slight slow-down of the fast path, as the radix tree could
be higher than necessary.
To limit the radix tree height, I have chosen the following limits:
1) The cycling is done over in_use*1.5.
2) At least, the cycling is done over
"normal" ipcnmi mode: RADIX_TREE_MAP_SIZE elements
"ipcmni_extended": 4096 elements
Result:
- for normal mode:
No change for <= 42 active ipc elements. With more than 42
active ipc elements, a 2nd level would be added to the radix
tree.
Without cyclic allocation, a 2nd level would be added only with
more than 63 active elements.
- for extended mode:
Cycling creates always at least a 2-level radix tree.
With more than 2730 active objects, a 3rd level would be
added, instead of > 4095 active objects until the 3rd level
is added without cyclic allocation.
For a 2-level radix tree compared to a 1-level radix tree, I have
observed < 1% performance impact.
Notes:
1) Normal "x=semget();y=semget();" is unaffected: Then the idx
is e.g. a and a+1, regardless if idr_alloc() or idr_alloc_cyclic()
is used.
2) The -1% happens in a microbenchmark after this situation:
x=semget();
for(i=0;i<4000;i++) {t=semget();semctl(t,0,IPC_RMID);}
y=semget();
Now perform semget calls on x and y that do not sleep.
3) The worst-case reuse cycle time is unfortunately unaffected:
If you have 2^24-1 ipc objects allocated, and get/remove the last
possible element in a loop, then the id is reused after 128
get/remove pairs.
Performance check:
A microbenchmark that performes no-op semop() randomly on two IDs,
with only these two IDs allocated.
The IDs were set using /proc/sys/kernel/sem_next_id.
The test was run 5 times, averages are shown.
1 & 2: Base (6.22 seconds for 10.000.000 semops)
1 & 40: -0.2%
1 & 3348: - 0.8%
1 & 27348: - 1.6%
1 & 15777204: - 3.2%
Or: ~12.6 cpu cycles per additional radix tree level.
The cpu is an Intel I3-5010U. ~1300 cpu cycles/syscall is slower
than what I remember (spectre impact?).
V2 of the patch:
- use "min" and "max"
- use RADIX_TREE_MAP_SIZE * RADIX_TREE_MAP_SIZE instead of
(2<<12).
[akpm@linux-foundation.org: fix max() warning]
Link: http://lkml.kernel.org/r/20190329204930.21620-3-longman@redhat.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Waiman Long <longman@redhat.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rewrite, based on the patch from Waiman Long:
The mixing in of a sequence number into the IPC IDs is probably to avoid
ID reuse in userspace as much as possible. With ipcmni_extend mode, the
number of usable sequence numbers is greatly reduced leading to higher
chance of ID reuse.
To address this issue, we need to conserve the sequence number space as
much as possible. Right now, the sequence number is incremented for
every new ID created. In reality, we only need to increment the
sequence number when new allocated ID is not greater than the last one
allocated. It is in such case that the new ID may collide with an
existing one. This is being done irrespective of the ipcmni mode.
In order to avoid any races, the index is first allocated and then the
pointer is replaced.
Changes compared to the initial patch:
- Handle failures from idr_alloc().
- Avoid that concurrent operations can see the wrong sequence number.
(This is achieved by using idr_replace()).
- IPCMNI_SEQ_SHIFT is not a constant, thus renamed to
ipcmni_seq_shift().
- IPCMNI_SEQ_MAX is not a constant, thus renamed to ipcmni_seq_max().
Link: http://lkml.kernel.org/r/20190329204930.21620-2-longman@redhat.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Arnaldo Carvalho de Melo