rtla/utils: Add idle state disabling via libcpupower

Add functions to utils.c to disable idle states through functions of
libcpupower. This will serve as the basis for disabling idle states
per cpu

rtla/utils: Add idle state disabling via libcpupower

Add functions to utils.c to disable idle states through functions of
libcpupower. This will serve as the basis for disabling idle states
per cpu when running timerlat.

Link: https://lore.kernel.org/[email protected]
Signed-off-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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tools/rtla: fix collision with glibc sched_attr/sched_set_attr

glibc commit 21571ca0d703 ("Linux: Add the sched_setattr
and sched_getattr functions") now also provides 'struct sched_attr'
and sched_

tools/rtla: fix collision with glibc sched_attr/sched_set_attr

glibc commit 21571ca0d703 ("Linux: Add the sched_setattr
and sched_getattr functions") now also provides 'struct sched_attr'
and sched_setattr() which collide with the ones from rtla.

In file included from src/trace.c:11:
src/utils.h:49:8: error: redefinition of ‘struct sched_attr’
49 | struct sched_attr {
| ^~~~~~~~~~
In file included from /usr/include/bits/sched.h:60,
from /usr/include/sched.h:43,
from /usr/include/tracefs/tracefs.h:10,
from src/trace.c:4:
/usr/include/linux/sched/types.h:98:8: note: originally defined here
98 | struct sched_attr {
| ^~~~~~~~~~

Define 'struct sched_attr' conditionally, similar to what strace did:
https://lore.kernel.org/all/[email protected]/
and rename rtla's version of sched_setattr() to avoid collision.

Link: https://lore.kernel.org/8088f66a7a57c1b209cd8ae0ae7c336a7f8c930d.1728572865.git.jstancek@redhat.com
Signed-off-by: Jan Stancek <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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tools/rtla: drop __NR_sched_getattr

It's not used since commit 084ce16df0f0 ("tools/rtla:
Remove unused sched_getattr() function").

Link: https://lore.kernel.org/c355dc9ad23470098d6a8d0f31fbd702551

tools/rtla: drop __NR_sched_getattr

It's not used since commit 084ce16df0f0 ("tools/rtla:
Remove unused sched_getattr() function").

Link: https://lore.kernel.org/c355dc9ad23470098d6a8d0f31fbd702551c9ea8.1728552769.git.jstancek@redhat.com
Signed-off-by: Jan Stancek <[email protected]>
Reviewed-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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tools/rtla: Replace setting prio with nice for SCHED_OTHER

Since the sched_priority for SCHED_OTHER is always 0, it makes no
sence to set it.
Setting nice for SCHED_OTHER seems more meaningful.

Lin

tools/rtla: Replace setting prio with nice for SCHED_OTHER

Since the sched_priority for SCHED_OTHER is always 0, it makes no
sence to set it.
Setting nice for SCHED_OTHER seems more meaningful.

Link: https://lkml.kernel.org/r/[email protected]

Cc: [email protected]
Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Signed-off-by: limingming3 <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>

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tools/rtla: Remove unused sched_getattr() function

Clang is reporting:

$ make HOSTCC=clang CC=clang LLVM_IAS=1
[...]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions -fstack-protector-st

tools/rtla: Remove unused sched_getattr() function

Clang is reporting:

$ make HOSTCC=clang CC=clang LLVM_IAS=1
[...]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions -fstack-protector-strong -fasynchronous-unwind-tables -fstack-clash-protection -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS $(pkg-config --cflags libtracefs) -c -o src/utils.o src/utils.c
src/utils.c:241:19: warning: unused function 'sched_getattr' [-Wunused-function]
241 | static inline int sched_getattr(pid_t pid, struct sched_attr *attr,
| ^~~~~~~~~~~~~
1 warning generated.

Which is correct, so remove the unused function.

Link: https://lkml.kernel.org/r/eaed7ba122c4ae88ce71277c824ef41cbf789385.1707217097.git.bristot@kernel.org

Cc: [email protected]
Cc: Masami Hiramatsu <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Bill Wendling <[email protected]>
Cc: Justin Stitt <[email protected]>
Cc: Donald Zickus <[email protected]>
Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>

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tools/rtla: Fix clang warning about mount_point var size

clang is reporting this warning:

$ make HOSTCC=clang CC=clang LLVM_IAS=1
[...]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions

tools/rtla: Fix clang warning about mount_point var size

clang is reporting this warning:

$ make HOSTCC=clang CC=clang LLVM_IAS=1
[...]
clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions
-fstack-protector-strong -fasynchronous-unwind-tables
-fstack-clash-protection -Wall -Werror=format-security
-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
$(pkg-config --cflags libtracefs) -c -o src/utils.o src/utils.c

src/utils.c:548:66: warning: 'fscanf' may overflow; destination buffer in argument 3 has size 1024, but the corresponding specifier may require size 1025 [-Wfortify-source]
548 | while (fscanf(fp, "%*s %" STR(MAX_PATH) "s %99s %*s %*d %*d\n", mount_point, type) == 2) {
| ^

Increase mount_point variable size to MAX_PATH+1 to avoid the overflow.

Link: https://lkml.kernel.org/r/1b46712e93a2f4153909514a36016959dcc4021c.1707217097.git.bristot@kernel.org

Cc: [email protected]
Cc: Masami Hiramatsu <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Bill Wendling <[email protected]>
Cc: Justin Stitt <[email protected]>
Cc: Donald Zickus <[email protected]>
Fixes: a957cbc02531 ("rtla: Add -C cgroup support")
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>

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rtla: Fix uninitialized variable found

Variable found is not being initialized, in the case where the desired
mount is not found the variable contains garbage. Fix this by initializing
it to zero.

rtla: Fix uninitialized variable found

Variable found is not being initialized, in the case where the desired
mount is not found the variable contains garbage. Fix this by initializing
it to zero.

Link: https://lore.kernel.org/all/[email protected]/

Fixes: a957cbc02531 ("rtla: Add -C cgroup support")
Signed-off-by: Colin Ian King <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>

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rtla/timerlat_top: Add timerlat user-space support

Add the support for running timerlat threads in user-space. In this
mode, enabled with -u/--user-threads, timerlat dispatches user-space
processes

rtla/timerlat_top: Add timerlat user-space support

Add the support for running timerlat threads in user-space. In this
mode, enabled with -u/--user-threads, timerlat dispatches user-space
processes that will loop in the timerlat_fd, measuring the overhead
for going to user-space and then returning to the kernel - in addition
to the existing measurements.

Here is one example of the tool's output with -u enabled:

$ sudo timerlat top -u -d 600 -q
Timer Latency
0 00:10:01 | IRQ Timer Latency (us) | Thread Timer Latency (us) | Ret user Timer Latency (us)
CPU COUNT | cur min avg max | cur min avg max | cur min avg max
0 #600001 | 0 0 0 3 | 2 1 2 9 | 3 2 3 15
1 #600001 | 0 0 0 2 | 2 1 2 13 | 2 2 3 18
2 #600001 | 0 0 0 10 | 2 1 2 16 | 3 2 3 20
3 #600001 | 0 0 0 7 | 2 1 2 10 | 3 2 3 11
4 #600000 | 0 0 0 16 | 2 1 2 41 | 3 2 3 58
5 #600000 | 0 0 0 3 | 2 1 2 10 | 3 2 3 13
6 #600000 | 0 0 0 5 | 2 1 2 7 | 3 2 3 10
7 #600000 | 0 0 0 1 | 2 1 2 7 | 3 2 3 10

The tuning setup like -p or -C work for the user-space threads as well.

Link: https://lkml.kernel.org/r/758ad2292a0a1d884138d08219e1a0f572d257a2.1686066600.git.bristot@kernel.org

Cc: William White <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Tested-by: Juri Lelli <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Automatically move rtla to a house-keeping cpu

When the user sets -c <cpu-list> try to move rtla out of the <cpu-list>,
even without an -H option. This is useful to avoid having rtla
interferi

rtla: Automatically move rtla to a house-keeping cpu

When the user sets -c <cpu-list> try to move rtla out of the <cpu-list>,
even without an -H option. This is useful to avoid having rtla
interfering with the workload.

This works by removing <cpu-list> from rtla's current affinity.

If rtla fails to move itself away it is not that of a problem as this
is an automatic measure.

Link: https://lkml.kernel.org/r/c54304d90c777310fb85a3e658d1449173759aab.1686066600.git.bristot@kernel.org

Cc: William White <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Tested-by: Juri Lelli <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Change monitored_cpus from char * to cpu_set_t

Use a cpumask instead of a char *, reducing memory footprint and code.

No functional change, and in preparation for auto house-keeping.

Link: h

rtla: Change monitored_cpus from char * to cpu_set_t

Use a cpumask instead of a char *, reducing memory footprint and code.

No functional change, and in preparation for auto house-keeping.

Link: https://lkml.kernel.org/r/54c46293261d13cb1042d0314486539eeb45fe5d.1686066600.git.bristot@kernel.org

Cc: William White <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Tested-by: Juri Lelli <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Add --house-keeping option

To avoid having rtla interfering with the measurement threads, add an
option for the user to set the CPUs in which rtla should run. For
instance:

# rtla timerlat

rtla: Add --house-keeping option

To avoid having rtla interfering with the measurement threads, add an
option for the user to set the CPUs in which rtla should run. For
instance:

# rtla timerlat top -H 0 -c 1-7

Will place rtla in the CPU 0, while running the measurement threads in
the CPU 1-7.

Link: https://lkml.kernel.org/r/6a6c78a579a96ba8b02ae67ee1e0ba2cb5e03c4a.1686066600.git.bristot@kernel.org

Cc: William White <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Tested-by: Juri Lelli <[email protected]>
Suggested-by: Juri Lelli <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Add -C cgroup support

The -C option sets a cgroup to the tracer's threads. If the -C option is
passed without arguments, the tracer's thread will inherit rtla's
cgroup. Otherwise, the threads

rtla: Add -C cgroup support

The -C option sets a cgroup to the tracer's threads. If the -C option is
passed without arguments, the tracer's thread will inherit rtla's
cgroup. Otherwise, the threads will be placed on the cgroup passed
to the option.

Link: https://lkml.kernel.org/r/cb051477331d292f17c08bf1d66f0e0384bbe5a5.1686066600.git.bristot@kernel.org

Cc: William White <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Tested-by: Juri Lelli <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Define syscall numbers for riscv

RISC-V uses the same (generic) syscall numbers as ARM64.

Link: https://lkml.kernel.org/r/[email protected]

Signed-off-by: Andreas Schwab <[email protected]

rtla: Define syscall numbers for riscv

RISC-V uses the same (generic) syscall numbers as ARM64.

Link: https://lkml.kernel.org/r/[email protected]

Signed-off-by: Andreas Schwab <[email protected]>
Acked-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/utils: Use calloc and check the potential memory allocation failure

Replace malloc with calloc and add memory allocating check
of mon_cpus before used.

Link: https://lkml.kernel.org/r/20220615

rtla/utils: Use calloc and check the potential memory allocation failure

Replace malloc with calloc and add memory allocating check
of mon_cpus before used.

Link: https://lkml.kernel.org/r/[email protected]

Fixes: 7d0dc9576dc3 ("rtla/timerlat: Add --dma-latency option")
Signed-off-by: jianchunfu <[email protected]>
Acked-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Remove procps-ng dependency

Daniel Wagner reported to me that readproc.h got deprecated. Also,
while the procps-ng library was available on Fedora, it was not available
on RHEL, which is a pie

rtla: Remove procps-ng dependency

Daniel Wagner reported to me that readproc.h got deprecated. Also,
while the procps-ng library was available on Fedora, it was not available
on RHEL, which is a piece of evidence that it was not that used.

rtla uses procps-ng only to find the PID of the tracers' workload.

I used the procps-ng library to avoid reinventing the wheel. But in this
case, reinventing the wheel took me less time than the time we already
took trying to work around problems.

Implement a function that reads /proc/ entries, checking if:
- the entry is a directory
- the directory name is composed only of digits (PID)
- the directory contains the comm file
- the comm file contains a comm that matches the tracers'
workload prefix.
- then return true; otherwise, return false.

And use it instead of procps-ng.

Link: https://lkml.kernel.org/r/e8276e122ee9eb2c5a0ba8e673fb6488b924b825.1652423574.git.bristot@kernel.org

Cc: John Kacur <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Tao Zhou <[email protected]>
Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Reported-by: Daniel Wagner <[email protected]>
Reviewed-by: Daniel Wagner <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Fix __set_sched_attr error message

rtla's function __set_sched_attr() was borrowed from stalld, but I
forgot to update the error message to something meaningful for rtla.

Update the error me

rtla: Fix __set_sched_attr error message

rtla's function __set_sched_attr() was borrowed from stalld, but I
forgot to update the error message to something meaningful for rtla.

Update the error message from:
boost_with_deadline failed to boost pid PID: STRERROR
to a proper one:
Failed to set sched attributes to the pid PID: STRERROR

Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/timerlat: Add --dma-latency option

Add the --dma-latency to set /dev/cpu_dma_latency to the
specified value, this aims to avoid having exit from idle
states latencies that could be influencing

rtla/timerlat: Add --dma-latency option

Add the --dma-latency to set /dev/cpu_dma_latency to the
specified value, this aims to avoid having exit from idle
states latencies that could be influencing the analysis.

Link: https://lkml.kernel.org/r/72ddb0d913459f13217086dadafad88a7c46dd28.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/utils: Fix session duration parsing

Use gmtime to format the duration time. This avoids problems when the
system uses local time different of Pisa's Local Time.

Link: https://lkml.kernel.org/r

rtla/utils: Fix session duration parsing

Use gmtime to format the duration time. This avoids problems when the
system uses local time different of Pisa's Local Time.

Link: https://lkml.kernel.org/r/a2f0a37bc006c2561bb8ecd871cd70532b4a9f2d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Helper functions for rtla

This is a set of utils and tracer helper functions. They are used by
rtla mostly to parse config, display data and some trace operations that
are not part of libtrace

rtla: Helper functions for rtla

This is a set of utils and tracer helper functions. They are used by
rtla mostly to parse config, display data and some trace operations that
are not part of libtracefs (because they are only useful it for this
case).

Link: https://lkml.kernel.org/r/a94c128aba9e6e66d502b7094f2e8c7ac95b12e5.1639158831.git.bristot@kernel.org

Cc: Tao Zhou <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Tom Zanussi <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: John Kacur <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>

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