[PATCH v4 0/8] Generic IRQ entry/exit support for powerpc

Mukesh Kumar Chaurasiya posted 8 patches 2 weeks ago
arch/powerpc/Kconfig                    |   1 +
arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
arch/powerpc/include/asm/hw_irq.h       |   4 +-
arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
arch/powerpc/include/asm/kasan.h        |  15 +-
arch/powerpc/include/asm/ptrace.h       |   6 +-
arch/powerpc/include/asm/signal.h       |   1 -
arch/powerpc/include/asm/stacktrace.h   |   6 +
arch/powerpc/include/asm/syscall.h      |   5 +
arch/powerpc/include/asm/thread_info.h  |   1 +
arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
arch/powerpc/kernel/interrupt.c         | 254 ++---------
arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
arch/powerpc/kernel/signal.c            |  25 +-
arch/powerpc/kernel/syscall.c           | 119 +-----
arch/powerpc/kernel/traps.c             |   2 +-
arch/powerpc/kernel/watchdog.c          |   2 +-
arch/powerpc/perf/core-book3s.c         |   2 +-
18 files changed, 690 insertions(+), 828 deletions(-)
create mode 100644 arch/powerpc/include/asm/entry-common.h
[PATCH v4 0/8] Generic IRQ entry/exit support for powerpc
Posted by Mukesh Kumar Chaurasiya 2 weeks ago
Adding support for the generic irq entry/exit handling for PowerPC. The
goal is to bring PowerPC in line with other architectures that already
use the common irq entry infrastructure, reducing duplicated code and
making it easier to share future changes in entry/exit paths.

This is slightly tested of ppc64le and ppc32.

The performance benchmarks are below:

perf bench syscall usec/op (-ve is improvement)

| Syscall | Base        | test        | change % |
| ------- | ----------- | ----------- | -------- |
| basic   | 0.093543    | 0.093023    | -0.56    |
| execve  | 446.557781  | 450.107172  | +0.79    |
| fork    | 1142.204391 | 1156.377214 | +1.24    |
| getpgid | 0.097666    | 0.092677    | -5.11    |

perf bench syscall ops/sec (+ve is improvement)

| Syscall | Base     | New      | change % |
| ------- | -------- | -------- | -------- |
| basic   | 10690548 | 10750140 | +0.56    |
| execve  | 2239     | 2221     | -0.80    |
| fork    | 875      | 864      | -1.26    |
| getpgid | 10239026 | 10790324 | +5.38    |


IPI latency benchmark (-ve is improvement)

| Metric         | Base (ns)     | New (ns)      | % Change |
| -------------- | ------------- | ------------- | -------- |
| Dry run        | 583136.56     | 584136.35     | 0.17%    |
| Self IPI       | 4167393.42    | 4149093.90    | -0.44%   |
| Normal IPI     | 61769347.82   | 61753728.39   | -0.03%   |
| Broadcast IPI  | 2235584825.02 | 2227521401.45 | -0.36%   |
| Broadcast lock | 2164964433.31 | 2125658641.76 | -1.82%   |


Thats very close to performance earlier with arch specific handling.

Tests done:
 - Build and boot on ppc64le pseries.
 - Build and boot on ppc64le powernv8 powernv9 powernv10.
 - Build and boot on ppc32.
 - Performance benchmark done with perf syscall basic on pseries.

Changelog:
V3 -> V4
 - Fixed the issue in older gcc version where linker couldn't find
   mem functions
 - Merged IRQ enable and syscall enable into a single patch
 - Cleanup for unused functions done in separate patch.
 - Some other cosmetic changes
V3: https://lore.kernel.org/all/20251229045416.3193779-1-mkchauras@linux.ibm.com/

V2 -> V3
 - #ifdef CONFIG_GENERIC_IRQ_ENTRY removed from unnecessary places
 - Some functions made __always_inline
 - pt_regs padding changed to match 16byte interrupt stack alignment
 - And some cosmetic changes from reviews from earlier patch
V2: https://lore.kernel.org/all/20251214130245.43664-1-mkchauras@linux.ibm.com/

V1 -> V2
 - Fix an issue where context tracking was showing warnings for
   incorrect context
V1: https://lore.kernel.org/all/20251102115358.1744304-1-mkchauras@linux.ibm.com/

RFC -> PATCH V1
 - Fix for ppc32 spitting out kuap lock warnings.
 - ppc64le powernv8 crash fix.
 - Review comments incorporated from previous RFC.
RFC https://lore.kernel.org/all/20250908210235.137300-2-mchauras@linux.ibm.com/

Mukesh Kumar Chaurasiya (8):
  powerpc: rename arch_irq_disabled_regs
  powerpc: Prepare to build with generic entry/exit framework
  powerpc: introduce arch_enter_from_user_mode
  powerpc: Introduce syscall exit arch functions
  powerpc: add exit_flags field in pt_regs
  powerpc: Prepare for IRQ entry exit
  powerpc: Enable GENERIC_ENTRY feature
  powerpc: Remove unused functions

 arch/powerpc/Kconfig                    |   1 +
 arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
 arch/powerpc/include/asm/hw_irq.h       |   4 +-
 arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
 arch/powerpc/include/asm/kasan.h        |  15 +-
 arch/powerpc/include/asm/ptrace.h       |   6 +-
 arch/powerpc/include/asm/signal.h       |   1 -
 arch/powerpc/include/asm/stacktrace.h   |   6 +
 arch/powerpc/include/asm/syscall.h      |   5 +
 arch/powerpc/include/asm/thread_info.h  |   1 +
 arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
 arch/powerpc/kernel/interrupt.c         | 254 ++---------
 arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
 arch/powerpc/kernel/signal.c            |  25 +-
 arch/powerpc/kernel/syscall.c           | 119 +-----
 arch/powerpc/kernel/traps.c             |   2 +-
 arch/powerpc/kernel/watchdog.c          |   2 +-
 arch/powerpc/perf/core-book3s.c         |   2 +-
 18 files changed, 690 insertions(+), 828 deletions(-)
 create mode 100644 arch/powerpc/include/asm/entry-common.h

-- 
2.52.0
Re: [PATCH v4 0/8] Generic IRQ entry/exit support for powerpc
Posted by Samir M 1 week ago
On 23/01/26 1:09 pm, Mukesh Kumar Chaurasiya wrote:
> Adding support for the generic irq entry/exit handling for PowerPC. The
> goal is to bring PowerPC in line with other architectures that already
> use the common irq entry infrastructure, reducing duplicated code and
> making it easier to share future changes in entry/exit paths.
>
> This is slightly tested of ppc64le and ppc32.
>
> The performance benchmarks are below:
>
> perf bench syscall usec/op (-ve is improvement)
>
> | Syscall | Base        | test        | change % |
> | ------- | ----------- | ----------- | -------- |
> | basic   | 0.093543    | 0.093023    | -0.56    |
> | execve  | 446.557781  | 450.107172  | +0.79    |
> | fork    | 1142.204391 | 1156.377214 | +1.24    |
> | getpgid | 0.097666    | 0.092677    | -5.11    |
>
> perf bench syscall ops/sec (+ve is improvement)
>
> | Syscall | Base     | New      | change % |
> | ------- | -------- | -------- | -------- |
> | basic   | 10690548 | 10750140 | +0.56    |
> | execve  | 2239     | 2221     | -0.80    |
> | fork    | 875      | 864      | -1.26    |
> | getpgid | 10239026 | 10790324 | +5.38    |
>
>
> IPI latency benchmark (-ve is improvement)
>
> | Metric         | Base (ns)     | New (ns)      | % Change |
> | -------------- | ------------- | ------------- | -------- |
> | Dry run        | 583136.56     | 584136.35     | 0.17%    |
> | Self IPI       | 4167393.42    | 4149093.90    | -0.44%   |
> | Normal IPI     | 61769347.82   | 61753728.39   | -0.03%   |
> | Broadcast IPI  | 2235584825.02 | 2227521401.45 | -0.36%   |
> | Broadcast lock | 2164964433.31 | 2125658641.76 | -1.82%   |
>
>
> Thats very close to performance earlier with arch specific handling.
>
> Tests done:
>   - Build and boot on ppc64le pseries.
>   - Build and boot on ppc64le powernv8 powernv9 powernv10.
>   - Build and boot on ppc32.
>   - Performance benchmark done with perf syscall basic on pseries.
>
> Changelog:
> V3 -> V4
>   - Fixed the issue in older gcc version where linker couldn't find
>     mem functions
>   - Merged IRQ enable and syscall enable into a single patch
>   - Cleanup for unused functions done in separate patch.
>   - Some other cosmetic changes
> V3: https://lore.kernel.org/all/20251229045416.3193779-1-mkchauras@linux.ibm.com/
>
> V2 -> V3
>   - #ifdef CONFIG_GENERIC_IRQ_ENTRY removed from unnecessary places
>   - Some functions made __always_inline
>   - pt_regs padding changed to match 16byte interrupt stack alignment
>   - And some cosmetic changes from reviews from earlier patch
> V2: https://lore.kernel.org/all/20251214130245.43664-1-mkchauras@linux.ibm.com/
>
> V1 -> V2
>   - Fix an issue where context tracking was showing warnings for
>     incorrect context
> V1: https://lore.kernel.org/all/20251102115358.1744304-1-mkchauras@linux.ibm.com/
>
> RFC -> PATCH V1
>   - Fix for ppc32 spitting out kuap lock warnings.
>   - ppc64le powernv8 crash fix.
>   - Review comments incorporated from previous RFC.
> RFC https://lore.kernel.org/all/20250908210235.137300-2-mchauras@linux.ibm.com/
>
> Mukesh Kumar Chaurasiya (8):
>    powerpc: rename arch_irq_disabled_regs
>    powerpc: Prepare to build with generic entry/exit framework
>    powerpc: introduce arch_enter_from_user_mode
>    powerpc: Introduce syscall exit arch functions
>    powerpc: add exit_flags field in pt_regs
>    powerpc: Prepare for IRQ entry exit
>    powerpc: Enable GENERIC_ENTRY feature
>    powerpc: Remove unused functions
>
>   arch/powerpc/Kconfig                    |   1 +
>   arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
>   arch/powerpc/include/asm/hw_irq.h       |   4 +-
>   arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
>   arch/powerpc/include/asm/kasan.h        |  15 +-
>   arch/powerpc/include/asm/ptrace.h       |   6 +-
>   arch/powerpc/include/asm/signal.h       |   1 -
>   arch/powerpc/include/asm/stacktrace.h   |   6 +
>   arch/powerpc/include/asm/syscall.h      |   5 +
>   arch/powerpc/include/asm/thread_info.h  |   1 +
>   arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
>   arch/powerpc/kernel/interrupt.c         | 254 ++---------
>   arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
>   arch/powerpc/kernel/signal.c            |  25 +-
>   arch/powerpc/kernel/syscall.c           | 119 +-----
>   arch/powerpc/kernel/traps.c             |   2 +-
>   arch/powerpc/kernel/watchdog.c          |   2 +-
>   arch/powerpc/perf/core-book3s.c         |   2 +-
>   18 files changed, 690 insertions(+), 828 deletions(-)
>   create mode 100644 arch/powerpc/include/asm/entry-common.h
Hi Mukesh,

I verified this patch with the following configuration and test coverage.

Test configuration:

  * Kernel version: 6.19.0-rc6
  * Number of CPUs: 80

Tests that are performed:
1. Kernel selftests
2. LTP
3. will-it-scale
4. stress-ng (IRQ and syscall focused)
5. DLPAR with SMT stress testing
6. DLPAR with CPU folding scenarios
7. ptrace, ftrace and perf related tests.
8. Build and boot.

No functional issues were observed during testing.


Performance Tests:
perf bench syscall usec/op:(+ve is regression)
syscall  | without_patch | with_patch |  %change |
--------------------------------------------------
getppid  |   0.100       |  0.102    |  +2.0 %  |
fork.    |   363.281     |  369.995  |  +1.85%  |
execve.  |   360.610     |  360.826  |  +0.06%  |


perf bench syscall ops/sec:(-ve is regression)
syscall  | without_patch | with_patch  |  %change |
--------------------------------------------------
getppid  |   10,048,674  | 9,851,574|   −1.96% |
fork.    |   2,752       |    2,703   |   −1.78% |
execve.  |   2,772       | 2,771    |   −0.04% |


IPI latency benchmark (-ve is improvement)

| Metric  | without_patch (ns)| with_patch (ns) | % Change |
| -------------- | ----------------- | --------------- | -------- |
| Dry run        | 202259.20        | 201962.38       | -0.15%   |
| Self IPI       | 3565899.21       | 3271122.04      | -8.27%   |
| Normal IPI     | 47146345.28       | 42920014.89     | -8.97%   |
| Broadcast IPI  | 3920749623.87     | 3838799420.04   | -2.09%   |
| Broadcast lock | 3877260906.55     | 3803805814.03   | -1.89%   |

Please add the below tag,

Tested-by: Samir M <samir@linux.ibm.com>


Regards,
Samir.
Re: [PATCH v4 0/8] Generic IRQ entry/exit support for powerpc
Posted by David Gow 1 week ago
On Fri, 23 Jan 2026 at 15:39, Mukesh Kumar Chaurasiya
<mkchauras@linux.ibm.com> wrote:
>
> Adding support for the generic irq entry/exit handling for PowerPC. The
> goal is to bring PowerPC in line with other architectures that already
> use the common irq entry infrastructure, reducing duplicated code and
> making it easier to share future changes in entry/exit paths.
>
> This is slightly tested of ppc64le and ppc32.
>
> The performance benchmarks are below:
>
> perf bench syscall usec/op (-ve is improvement)
>
> | Syscall | Base        | test        | change % |
> | ------- | ----------- | ----------- | -------- |
> | basic   | 0.093543    | 0.093023    | -0.56    |
> | execve  | 446.557781  | 450.107172  | +0.79    |
> | fork    | 1142.204391 | 1156.377214 | +1.24    |
> | getpgid | 0.097666    | 0.092677    | -5.11    |
>
> perf bench syscall ops/sec (+ve is improvement)
>
> | Syscall | Base     | New      | change % |
> | ------- | -------- | -------- | -------- |
> | basic   | 10690548 | 10750140 | +0.56    |
> | execve  | 2239     | 2221     | -0.80    |
> | fork    | 875      | 864      | -1.26    |
> | getpgid | 10239026 | 10790324 | +5.38    |
>
>
> IPI latency benchmark (-ve is improvement)
>
> | Metric         | Base (ns)     | New (ns)      | % Change |
> | -------------- | ------------- | ------------- | -------- |
> | Dry run        | 583136.56     | 584136.35     | 0.17%    |
> | Self IPI       | 4167393.42    | 4149093.90    | -0.44%   |
> | Normal IPI     | 61769347.82   | 61753728.39   | -0.03%   |
> | Broadcast IPI  | 2235584825.02 | 2227521401.45 | -0.36%   |
> | Broadcast lock | 2164964433.31 | 2125658641.76 | -1.82%   |
>
>
> Thats very close to performance earlier with arch specific handling.
>
> Tests done:
>  - Build and boot on ppc64le pseries.
>  - Build and boot on ppc64le powernv8 powernv9 powernv10.
>  - Build and boot on ppc32.
>  - Performance benchmark done with perf syscall basic on pseries.
>

Passes the irq_test_cases KUnit suite on (qemu) powerpc(64),
powerpcle, and powerpc32 targets.

./tools/testing/kunit/kunit.py run --arch powerpc  irq_test_cases
./tools/testing/kunit/kunit.py run --arch powerpcle  irq_test_cases
./tools/testing/kunit/kunit.py run --arch powerpc32  irq_test_cases

Tested-by: David Gow <davidgow@google.com>

Cheers,
-- David

> Changelog:
> V3 -> V4
>  - Fixed the issue in older gcc version where linker couldn't find
>    mem functions
>  - Merged IRQ enable and syscall enable into a single patch
>  - Cleanup for unused functions done in separate patch.
>  - Some other cosmetic changes
> V3: https://lore.kernel.org/all/20251229045416.3193779-1-mkchauras@linux.ibm.com/
>
> V2 -> V3
>  - #ifdef CONFIG_GENERIC_IRQ_ENTRY removed from unnecessary places
>  - Some functions made __always_inline
>  - pt_regs padding changed to match 16byte interrupt stack alignment
>  - And some cosmetic changes from reviews from earlier patch
> V2: https://lore.kernel.org/all/20251214130245.43664-1-mkchauras@linux.ibm.com/
>
> V1 -> V2
>  - Fix an issue where context tracking was showing warnings for
>    incorrect context
> V1: https://lore.kernel.org/all/20251102115358.1744304-1-mkchauras@linux.ibm.com/
>
> RFC -> PATCH V1
>  - Fix for ppc32 spitting out kuap lock warnings.
>  - ppc64le powernv8 crash fix.
>  - Review comments incorporated from previous RFC.
> RFC https://lore.kernel.org/all/20250908210235.137300-2-mchauras@linux.ibm.com/
>
> Mukesh Kumar Chaurasiya (8):
>   powerpc: rename arch_irq_disabled_regs
>   powerpc: Prepare to build with generic entry/exit framework
>   powerpc: introduce arch_enter_from_user_mode
>   powerpc: Introduce syscall exit arch functions
>   powerpc: add exit_flags field in pt_regs
>   powerpc: Prepare for IRQ entry exit
>   powerpc: Enable GENERIC_ENTRY feature
>   powerpc: Remove unused functions
>
>  arch/powerpc/Kconfig                    |   1 +
>  arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
>  arch/powerpc/include/asm/hw_irq.h       |   4 +-
>  arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
>  arch/powerpc/include/asm/kasan.h        |  15 +-
>  arch/powerpc/include/asm/ptrace.h       |   6 +-
>  arch/powerpc/include/asm/signal.h       |   1 -
>  arch/powerpc/include/asm/stacktrace.h   |   6 +
>  arch/powerpc/include/asm/syscall.h      |   5 +
>  arch/powerpc/include/asm/thread_info.h  |   1 +
>  arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
>  arch/powerpc/kernel/interrupt.c         | 254 ++---------
>  arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
>  arch/powerpc/kernel/signal.c            |  25 +-
>  arch/powerpc/kernel/syscall.c           | 119 +-----
>  arch/powerpc/kernel/traps.c             |   2 +-
>  arch/powerpc/kernel/watchdog.c          |   2 +-
>  arch/powerpc/perf/core-book3s.c         |   2 +-
>  18 files changed, 690 insertions(+), 828 deletions(-)
>  create mode 100644 arch/powerpc/include/asm/entry-common.h
>
> --
> 2.52.0
>
> --
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Re: [PATCH v4 0/8] Generic IRQ entry/exit support for powerpc
Posted by Venkat 1 week ago

> On 23 Jan 2026, at 1:09 PM, Mukesh Kumar Chaurasiya <mkchauras@linux.ibm.com> wrote:
> 
> Adding support for the generic irq entry/exit handling for PowerPC. The
> goal is to bring PowerPC in line with other architectures that already
> use the common irq entry infrastructure, reducing duplicated code and
> making it easier to share future changes in entry/exit paths.
> 
> This is slightly tested of ppc64le and ppc32.
> 
> The performance benchmarks are below:
> 
> perf bench syscall usec/op (-ve is improvement)
> 
> | Syscall | Base        | test        | change % |
> | ------- | ----------- | ----------- | -------- |
> | basic   | 0.093543    | 0.093023    | -0.56    |
> | execve  | 446.557781  | 450.107172  | +0.79    |
> | fork    | 1142.204391 | 1156.377214 | +1.24    |
> | getpgid | 0.097666    | 0.092677    | -5.11    |
> 
> perf bench syscall ops/sec (+ve is improvement)
> 
> | Syscall | Base     | New      | change % |
> | ------- | -------- | -------- | -------- |
> | basic   | 10690548 | 10750140 | +0.56    |
> | execve  | 2239     | 2221     | -0.80    |
> | fork    | 875      | 864      | -1.26    |
> | getpgid | 10239026 | 10790324 | +5.38    |
> 
> 
> IPI latency benchmark (-ve is improvement)
> 
> | Metric         | Base (ns)     | New (ns)      | % Change |
> | -------------- | ------------- | ------------- | -------- |
> | Dry run        | 583136.56     | 584136.35     | 0.17%    |
> | Self IPI       | 4167393.42    | 4149093.90    | -0.44%   |
> | Normal IPI     | 61769347.82   | 61753728.39   | -0.03%   |
> | Broadcast IPI  | 2235584825.02 | 2227521401.45 | -0.36%   |
> | Broadcast lock | 2164964433.31 | 2125658641.76 | -1.82%   |
> 
> 
> Thats very close to performance earlier with arch specific handling.
> 
> Tests done:
> - Build and boot on ppc64le pseries.
> - Build and boot on ppc64le powernv8 powernv9 powernv10.
> - Build and boot on ppc32.
> - Performance benchmark done with perf syscall basic on pseries.
> 
> Changelog:
> V3 -> V4
> - Fixed the issue in older gcc version where linker couldn't find
>   mem functions
> - Merged IRQ enable and syscall enable into a single patch
> - Cleanup for unused functions done in separate patch.
> - Some other cosmetic changes
> V3: https://lore.kernel.org/all/20251229045416.3193779-1-mkchauras@linux.ibm.com/
> 
> V2 -> V3
> - #ifdef CONFIG_GENERIC_IRQ_ENTRY removed from unnecessary places
> - Some functions made __always_inline
> - pt_regs padding changed to match 16byte interrupt stack alignment
> - And some cosmetic changes from reviews from earlier patch
> V2: https://lore.kernel.org/all/20251214130245.43664-1-mkchauras@linux.ibm.com/
> 
> V1 -> V2
> - Fix an issue where context tracking was showing warnings for
>   incorrect context
> V1: https://lore.kernel.org/all/20251102115358.1744304-1-mkchauras@linux.ibm.com/
> 
> RFC -> PATCH V1
> - Fix for ppc32 spitting out kuap lock warnings.
> - ppc64le powernv8 crash fix.
> - Review comments incorporated from previous RFC.
> RFC https://lore.kernel.org/all/20250908210235.137300-2-mchauras@linux.ibm.com/
> 
> Mukesh Kumar Chaurasiya (8):
>  powerpc: rename arch_irq_disabled_regs
>  powerpc: Prepare to build with generic entry/exit framework
>  powerpc: introduce arch_enter_from_user_mode
>  powerpc: Introduce syscall exit arch functions
>  powerpc: add exit_flags field in pt_regs
>  powerpc: Prepare for IRQ entry exit
>  powerpc: Enable GENERIC_ENTRY feature
>  powerpc: Remove unused functions
> 
> arch/powerpc/Kconfig                    |   1 +
> arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
> arch/powerpc/include/asm/hw_irq.h       |   4 +-
> arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
> arch/powerpc/include/asm/kasan.h        |  15 +-
> arch/powerpc/include/asm/ptrace.h       |   6 +-
> arch/powerpc/include/asm/signal.h       |   1 -
> arch/powerpc/include/asm/stacktrace.h   |   6 +
> arch/powerpc/include/asm/syscall.h      |   5 +
> arch/powerpc/include/asm/thread_info.h  |   1 +
> arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
> arch/powerpc/kernel/interrupt.c         | 254 ++---------
> arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
> arch/powerpc/kernel/signal.c            |  25 +-
> arch/powerpc/kernel/syscall.c           | 119 +-----
> arch/powerpc/kernel/traps.c             |   2 +-
> arch/powerpc/kernel/watchdog.c          |   2 +-
> arch/powerpc/perf/core-book3s.c         |   2 +-
> 18 files changed, 690 insertions(+), 828 deletions(-)
> create mode 100644 arch/powerpc/include/asm/entry-common.h
> 
> -- 
> 2.52.0
> 

Tested this patch set, and it builds successfully. Also ran ltp, ptrace, ftrace, perf related tests and no crash or warnings observed. Please add below tag.

Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>

Regards,
Venkat.
Re: [PATCH v4 0/8] Generic IRQ entry/exit support for powerpc
Posted by Shrikanth Hegde 2 weeks ago
Hi Mukesh.

On 1/23/26 1:09 PM, Mukesh Kumar Chaurasiya wrote:
> Adding support for the generic irq entry/exit handling for PowerPC. The
> goal is to bring PowerPC in line with other architectures that already
> use the common irq entry infrastructure, reducing duplicated code and
> making it easier to share future changes in entry/exit paths.
> 
> This is slightly tested of ppc64le and ppc32.
> 
> The performance benchmarks are below:
> 
> perf bench syscall usec/op (-ve is improvement)
> 
> | Syscall | Base        | test        | change % |
> | ------- | ----------- | ----------- | -------- |
> | basic   | 0.093543    | 0.093023    | -0.56    |
> | execve  | 446.557781  | 450.107172  | +0.79    |
> | fork    | 1142.204391 | 1156.377214 | +1.24    |
> | getpgid | 0.097666    | 0.092677    | -5.11    |
> 
> perf bench syscall ops/sec (+ve is improvement)
> 
> | Syscall | Base     | New      | change % |
> | ------- | -------- | -------- | -------- |
> | basic   | 10690548 | 10750140 | +0.56    |
> | execve  | 2239     | 2221     | -0.80    |
> | fork    | 875      | 864      | -1.26    |
> | getpgid | 10239026 | 10790324 | +5.38    |
> 
> 
> IPI latency benchmark (-ve is improvement)
> 
> | Metric         | Base (ns)     | New (ns)      | % Change |
> | -------------- | ------------- | ------------- | -------- |
> | Dry run        | 583136.56     | 584136.35     | 0.17%    |
> | Self IPI       | 4167393.42    | 4149093.90    | -0.44%   |
> | Normal IPI     | 61769347.82   | 61753728.39   | -0.03%   |
> | Broadcast IPI  | 2235584825.02 | 2227521401.45 | -0.36%   |
> | Broadcast lock | 2164964433.31 | 2125658641.76 | -1.82%   |
> 
> 
> Thats very close to performance earlier with arch specific handling.
> 
> Tests done:
>   - Build and boot on ppc64le pseries.
>   - Build and boot on ppc64le powernv8 powernv9 powernv10.
>   - Build and boot on ppc32.
>   - Performance benchmark done with perf syscall basic on pseries.
> 
> Changelog:
> V3 -> V4
>   - Fixed the issue in older gcc version where linker couldn't find
>     mem functions
>   - Merged IRQ enable and syscall enable into a single patch
>   - Cleanup for unused functions done in separate patch.
>   - Some other cosmetic changes
> V3: https://lore.kernel.org/all/20251229045416.3193779-1-mkchauras@linux.ibm.com/
> 
> V2 -> V3
>   - #ifdef CONFIG_GENERIC_IRQ_ENTRY removed from unnecessary places
>   - Some functions made __always_inline
>   - pt_regs padding changed to match 16byte interrupt stack alignment
>   - And some cosmetic changes from reviews from earlier patch
> V2: https://lore.kernel.org/all/20251214130245.43664-1-mkchauras@linux.ibm.com/
> 
> V1 -> V2
>   - Fix an issue where context tracking was showing warnings for
>     incorrect context
> V1: https://lore.kernel.org/all/20251102115358.1744304-1-mkchauras@linux.ibm.com/
> 
> RFC -> PATCH V1
>   - Fix for ppc32 spitting out kuap lock warnings.
>   - ppc64le powernv8 crash fix.
>   - Review comments incorporated from previous RFC.
> RFC https://lore.kernel.org/all/20250908210235.137300-2-mchauras@linux.ibm.com/
> 
> Mukesh Kumar Chaurasiya (8):
>    powerpc: rename arch_irq_disabled_regs
>    powerpc: Prepare to build with generic entry/exit framework
>    powerpc: introduce arch_enter_from_user_mode
>    powerpc: Introduce syscall exit arch functions
>    powerpc: add exit_flags field in pt_regs
>    powerpc: Prepare for IRQ entry exit
>    powerpc: Enable GENERIC_ENTRY feature
>    powerpc: Remove unused functions
> 
>   arch/powerpc/Kconfig                    |   1 +
>   arch/powerpc/include/asm/entry-common.h | 533 ++++++++++++++++++++++++
>   arch/powerpc/include/asm/hw_irq.h       |   4 +-
>   arch/powerpc/include/asm/interrupt.h    | 386 +++--------------
>   arch/powerpc/include/asm/kasan.h        |  15 +-
>   arch/powerpc/include/asm/ptrace.h       |   6 +-
>   arch/powerpc/include/asm/signal.h       |   1 -
>   arch/powerpc/include/asm/stacktrace.h   |   6 +
>   arch/powerpc/include/asm/syscall.h      |   5 +
>   arch/powerpc/include/asm/thread_info.h  |   1 +
>   arch/powerpc/include/uapi/asm/ptrace.h  |  14 +-
>   arch/powerpc/kernel/interrupt.c         | 254 ++---------
>   arch/powerpc/kernel/ptrace/ptrace.c     | 142 +------
>   arch/powerpc/kernel/signal.c            |  25 +-
>   arch/powerpc/kernel/syscall.c           | 119 +-----
>   arch/powerpc/kernel/traps.c             |   2 +-
>   arch/powerpc/kernel/watchdog.c          |   2 +-
>   arch/powerpc/perf/core-book3s.c         |   2 +-
>   18 files changed, 690 insertions(+), 828 deletions(-)
>   create mode 100644 arch/powerpc/include/asm/entry-common.h
> 

Ran it a bit on powernv (power9) too. Not warnings and similar
micro benchmark numbers.

I think this is in better shape now. With that,

for the series.
Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com>