This change is needed to properly lock I2C parent bus driver.
Prior to this change i2c_put_adapter() is misused, which may lead
to an overflow over zero of I2C bus driver user counter.
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
of_find_i2c_adapter_by_node() call requires quite often missing
put_device(), and i2c_put_adapter() releases a device locked by
i2c_get_adapter() only. In general module_put(adapter->owner) and
put_device(dev) are not interchangeable.
This is a common error reproduction scenario as a result of the
misusage described above (for clearness this is run on iMX6 platform
with HDMI and I2C bus drivers compiled as kernel modules):
root@mx6q:~# lsmod | grep i2c
i2c_imx 10213 0
root@mx6q:~# lsmod | grep dw_hdmi_imx
dw_hdmi_imx 3631 0
dw_hdmi 11846 1 dw_hdmi_imx
imxdrm 8674 3 dw_hdmi_imx,imx_ipuv3_crtc,imx_ldb
drm_kms_helper 113765 5 dw_hdmi,imxdrm,imx_ipuv3_crtc,imx_ldb
root@mx6q:~# rmmod dw_hdmi_imx
root@mx6q:~# lsmod | grep i2c
i2c_imx 10213 -1
^^^^^
root@mx6q:~# rmmod i2c_imx
rmmod: ERROR: Module i2c_imx is in use
To fix existing users of these interfaces and to avoid any further
confusion and misusage in future, add one more interface
of_get_i2c_adapter_by_node(), it is similar to i2c_get_adapter() in
sense that an I2C bus device driver found and locked by user can be
correctly unlocked by i2c_put_adapter().
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In addition to module_get()/module_put() add get_device()/put_device()
calls into i2c_get_adapter()/i2c_put_adapter() exported
interfaces. This is done to lock I2C bus device, if it is in use by a
client.
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The mentioned flag fixes a warning on Intel Edison board since one of the I2C
controller shares IRQ line with watchdog timer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This adds devicetree documentation for the bindings of the
ads7828 driver.
Signed-off-by: Denis Carikli <denis@eukrea.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add support for VCT-jig parallel port I2C adapter to i2c-parport.
The adapter schematic can be found here (in the RAR file):
http://remont-aud.net/shop/22/desc/vct-jig-komplekt-dlja-samostojatelnoj-sborki
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cadence 1.0 version has bugs which have been fixed in the cadence 1.4 version.
This patch removes the quirks present in the driver for cadence 1.4 version.
Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
[wsa: fixed indentation issues in r1p10_i2c_def]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tegra I2C controller required to configure the clock divisor
register inside controller to different value based on the clock
speed. The recommended clock divisor for the I2C controller for
standard/fast mode is 0x19 and for fast-mode plus is 0x10.
Add support to configure clock divisor register of I2C controller
based on bus clock rate.
This clock divisor is supported form T114 onwards.
Signed-off-by: Chaitanya Bandi <bandik@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Once the new configuration is set on the conifg register of
I2C controller, it is require to update the CONFIG_LOAD register
to transfer the new SW configuration to actual HW internal
registers that would be used in the actual logic.
It is like, SW is programming only shadow registers through
regular configuration and when these load_config bit fields
are set to 1, it causes the regular/shadows registers
configuration transferred to the HW internal active registers.
So SW has to set these bit fields at the end of all regular
registers configuration. And these config_load bits are HW
auto-clear bits. HW clears these bit fields once the register
configuration is moved to HW internal active registers. So SW
has to wait until these bits are auto-cleared before going
for any further programming
This mechanism is supported on T124 and after this SoCs.
Signed-off-by: Chaitanya Bandi <bandik@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Patch "i2c: omap: abolish variable name confusion" triggered a
coccinelle warning which we fix here:
drivers/i2c/busses/i2c-omap.c:1333:5-24: pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at line 1334
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In case of error conditions like Arbitration lost or NACK lets signal
the waiting process.
Handle error cases in the Rx path
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently only one interrupt is serviced in the isr.
In case the multiple interrupts happen simultenously we service and ack
only one of them. Check for all the causes in the isr and service them.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently there is no slave mode support in the driver
also in the isr we just ack it and do nothing.
So disable the AAS interrupt.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove the busy loop while waiting for bus busy.
Instead let the processor sleep.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently before every transfer the interrupts are disabled.
So incase the slave nacks in the middle of the transfer the
current transfer is not aborted. Upon enabling the interrupts
conditions like NACK , arbitration lost will not be masked.
Remove the disabling of the interrupts.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently before every transfer the controller is reinitialised.
We are already resetting the controller upon errors so upon every
transfer is a performance kill.
Remove the same.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The xiic_process is a 154 line code that runs in isr context currently
move it to thread context. Also the name xiic_process suggests that the
intension was to run in process context.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
[wsa: initialized irqreturn_t to IRQ_NONE instead of IRQ_HANDLED]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently the interrupts are disabled at the start of the
isr and enabled at the end of the isr. Remove the same.
In case the slave device NACKs the transaction while in the isr
the transfer will continue and the NACK interrupt will arrive
only after the isr is serviced.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch cleans up i2c_pxa_probe() function,
- Use devm_ variants wherever
This will clean both probe exit and i2c_pxa_remove() functions
- Check platform resource before parsing any other data from DT/platform
- Use dev_err on failure from i2c_add_numbered_adapter()
- Use pr_info instead of printk for KERN_INFO
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
[wsa: removed unneeded error prinout after devm_ioremap_resource]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Update i2c_pxa_scream_blue_murder() fn to print more information
in case of error.
Also, use dev_err variants instead of printk.
Signed-off-by: Jett.Zhou <jtzhou@marvell.com>
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fix below warning message, coming from 64 bit toolchain.
drivers/i2c/busses/i2c-pxa.c:1237:15:
warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
Signed-off-by: Yipeng Yao <ypyao@marvell.com>
[vaibhav.hiremath@linaro.org: Updated Changelog]
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Cc: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In case of timeout in pio mode of operation return I2C_RETRY.
This behavior will be same as interrupt mode of operation.
Signed-off-by: Shouming Wang <wangshm@marvell.com>
[vaibhav.hiremath@linaro.org: Updated changelog]
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Normally i2c controller works as master, so slave addr is not needed, or
it will impact some slave device (eg. ST NFC chip) i2c accesses, because
it has the same i2c address with controller.
For example,
On the pxa1928 based platform, where PMIC (88pm860) is present @0x30
address on TWSI0 interface, and if we set 0x30 as a slave address in
pxa1928 TWSI0 module, all the transactions towards PMIC would go for toss.
Signed-off-by: Jett.Zhou <jtzhou@marvell.com>
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
During suspend there may still be some i2c access happening, as the
interrupt is shared between multiple drivers.
And if we don't keep i2c irq ON, there may be i2c access timeout if
i2c is in irq mode of operation.
Signed-off-by: Raul Xiong <xjian@marvell.com>
Signed-off-by: Xiaofan Tian <tianxf@marvell.com>
[vaibhav.hiremath@linaro.org: updated Changelog]
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add a basic driver for the Renesas EMEV2 SoC. Based on the driver from
the BSP which was first worked on by Ian, and made ready for upstream by
me.
Signed-off-by: Ian Molton <ian.molton@codethink.co.uk>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We have a driver now for IIC, so disable reset for them.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
we're about to remove the module, so we can't
really schedule a PM transition in the future,
we must wait for it to finish.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
struct device pointers are usually called
dev. Calling our struct omap_i2c_dev pointers
also dev has caused enough confusion.
This is the result of a few simple sed rules
to convert all struct omap_i2c_dev pointers
to be called omap instead.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
there's no need to fetch the platform_device
in order to dereference it back to the dev
pointer to access drvdata, we can use
dev_get_drvdata() instead.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Start using pr_fmt and convert all remaining printk to use
pr_* family of macros.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
[wsa: remove print on kzalloc failure]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Now parport is using device model so use dev_* macros instead of printk.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Jiri Pirko says:
====================
mlxsw: Couple of fixes/adjustments
Ido Schimmel (5):
mlxsw: Call free_netdev when removing port
mlxsw: Make system port to local port mapping explicit
mlxsw: Simplify mlxsw_sx_port_xmit function
mlxsw: Use correct skb length when dumping payload
mlxsw: Fix use-after-free bug in mlxsw_sx_port_xmit
Jiri Pirko (2):
mlxsw: Make pci module dependent on HAS_DMA and HAS_IOMEM
mlxsw: Strip FCS from incoming packets
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Store the length of the skb before transmitting it and use it for stats
instead of skb->len, since skb might have been freed already.
This issue was discovered using the Kernel Address sanitizer (KASan).
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do not use the length of the transmitted skb (which was freed), but
that of the response skb.
This issue was discovered using the Kernel Address sanitizer (KASan).
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously we only checked if the transmission queue is not full in the
middle of the xmit function. This lead to complex logic due to the fact
that sometimes we need to reallocate the headroom for our Tx header.
Allow the switch driver to know if the transmission queue is not full
before sending the packet and remove this complex logic.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
FCS of incoming packets is already checked by HW. Just strip it out.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This resolves compile errors on um-allyesconfig.
Note that there are many other drivers which have the same issue.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
System ports are unique identifiers in a multi-ASIC environment that
represent all the available ports in the system. Local ports on the
other hand, are unique only within the local ASIC.
Since system port to local port mapping is not part of the HW-SW
contract and since only single-ASIC configurations are currently
supported, set an explicit 1:1 mapping by configuring the Switch System
Port Record (SSPR) register.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When removing a port's netdevice we should also free the memory
allocated by alloc_etherdev(). Do this by calling free_netdev() at the
end of the teardown sequence.
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fix double word "the the" in
Documentation/DocBook/networking/API-eth-get-headlen.html
Documentation/DocBook/networking/netdev.html
Documentation/DocBook/networking.xml
These files are generated from comment in source,
so I have to fix comment in net/ethernet/eth.c.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 4182 s2 states that if an IPv4 Explicit NULL label is the only
label on the stack, then after popping the resulting packet must be
treated as a IPv4 packet and forwarded based on the IPv4 header. The
same is true for IPv6 Explicit NULL with an IPv6 packet following.
Therefore, when installing the IPv4/IPv6 Explicit NULL label routes,
add an attribute that specifies the expected payload type for use at
forwarding time for determining the type of the encapsulated packet
instead of inspecting the first nibble of the packet.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kaixu Xia says:
====================
bpf: Introduce the new ability of eBPF programs to access hardware PMU counter
This patchset is base on the net-next:
git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
commit 9dc20a6496.
Previous patch v6 url:
https://lkml.org/lkml/2015/8/4/188
changes in V7:
- rebase the whole patch set to net-next tree(9dc20a64);
- split out the core perf APIs into Patch 1/5;
- change the return value of function perf_event_attrs()
from struct perf_event * to const struct perf_event * in
Patch 1/5;
- rename the function perf_event_read_internal() to perf_event_
read_local() and rewrite it in Patch 1/5;
- rename the function check_func_limit() to check_map_func
_compatibility() and remove the unnecessary pass pointer to
a pointer in Patch 4/5;
changes in V6:
- make the Patch 1/4 commit message more meaning and readable;
- remove the unnecessary comment in Patch 2/4 and make it clean;
- declare the function perf_event_release_kernel() in include/
linux/perf_event.h to fix the build error when CONFIG_PERF_EVENTS
isn't configured in Patch 2/4;
- add function perf_event_attrs() to get the struct perf_event_attr
in Patch 2/4.
- move the related code from kernel/trace/bpf_trace.c to kernel/
events/core.c and add function perf_event_read_internal() to
avoid poking inside of the event outside of perf code in Patch 3/4;
- generial the func & map match-pair with an array in Patch 3/4;
changes in V5:
- move struct fd_array_map_ops* fd_ops to bpf_map;
- move array perf event decrement refcnt function to
map_free;
- fix the NULL ptr of perf_event_get();
- move bpf_perf_event_read() to kernel/bpf/bpf_trace.c;
- get rid of the remaining struct bpf_prog;
- move the unnecessay cast on void *;
changes in V4:
- make the bpf_prog_array_map more generic;
- fix the bug of event refcnt leak;
- use more useful errno in bpf_perf_event_read();
changes in V3:
- collapse V2 patches 1-3 into one;
- drop the function map->ops->map_traverse_elem() and release
the struct perf_event in map_free;
- only allow to access bpf_perf_event_read() from programs;
- update the perf_event_array_map elem via xchg();
- pass index directly to bpf_perf_event_read() instead of
MAP_KEY;
changes in V2:
- put atomic_long_inc_not_zero() between fdget() and fdput();
- limit the event type to PERF_TYPE_RAW and PERF_TYPE_HARDWARE;
- Only read the event counter on current CPU or on current
process;
- add new map type BPF_MAP_TYPE_PERF_EVENT_ARRAY to store the
pointer to the struct perf_event;
- according to the perf_event_map_fd and key, the function
bpf_perf_event_read() can get the Hardware PMU counter value;
Patch 5/5 is a simple example and shows how to use this new eBPF
programs ability. The PMU counter data can be found in
/sys/kernel/debug/tracing/trace(trace_pipe).(the cycles PMU
value when 'kprobe/sys_write' sampling)
$ cat /sys/kernel/debug/tracing/trace_pipe
$ ./tracex6
...
syslog-ng-548 [000] d..1 76.905673: : CPU-0 681765271
syslog-ng-548 [000] d..1 76.905690: : CPU-0 681787855
syslog-ng-548 [000] d..1 76.905707: : CPU-0 681810504
syslog-ng-548 [000] d..1 76.905725: : CPU-0 681834771
syslog-ng-548 [000] d..1 76.905745: : CPU-0 681859519
syslog-ng-548 [000] d..1 76.905766: : CPU-0 681890419
syslog-ng-548 [000] d..1 76.905783: : CPU-0 681914045
syslog-ng-548 [000] d..1 76.905800: : CPU-0 681935950
syslog-ng-548 [000] d..1 76.905816: : CPU-0 681958299
ls-690 [005] d..1 82.241308: : CPU-5 3138451
sh-691 [004] d..1 82.244570: : CPU-4 7324988
<...>-699 [007] d..1 99.961387: : CPU-7 3194027
<...>-695 [003] d..1 99.961474: : CPU-3 288901
<...>-695 [003] d..1 99.961541: : CPU-3 383145
<...>-695 [003] d..1 99.961591: : CPU-3 450365
<...>-695 [003] d..1 99.961639: : CPU-3 515751
<...>-695 [003] d..1 99.961686: : CPU-3 579047
...
The detail of patches is as follow:
Patch 1/5 add the necessary core perf APIs perf_event_attrs(),
perf_event_get(),perf_event_read_local() when accessing events
counters in eBPF programs
Patch 2/5 rewrites part of the bpf_prog_array map code and make it
more generic;
Patch 3/5 introduces a new bpf map type. This map only stores the
pointer to struct perf_event;
Patch 4/5 implements function bpf_perf_event_read() that get the
selected hardware PMU conuter;
Patch 5/5 gives a simple example.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a simple example and shows how to use the new ability
to get the selected Hardware PMU counter value.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
According to the perf_event_map_fd and index, the function
bpf_perf_event_read() can convert the corresponding map
value to the pointer to struct perf_event and return the
Hardware PMU counter value.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new bpf map type 'BPF_MAP_TYPE_PERF_EVENT_ARRAY'.
This map only stores the pointer to struct perf_event. The
user space event FDs from perf_event_open() syscall are converted
to the pointer to struct perf_event and stored in map.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All the map backends are of generic nature. In order to avoid
adding much special code into the eBPF core, rewrite part of
the bpf_prog_array map code and make it more generic. So the
new perf_event_array map type can reuse most of code with
bpf_prog_array map and add fewer lines of special code.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add three core perf APIs:
- perf_event_attrs(): export the struct perf_event_attr from struct
perf_event;
- perf_event_get(): get the struct perf_event from the given fd;
- perf_event_read_local(): read the events counters active on the
current CPU;
These APIs are needed when accessing events counters in eBPF programs.
The API perf_event_read_local() comes from Peter and I add the
corresponding SOB.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
