Re: [PATCH v3 0/8] Generic IRQ entry/exit support for powerpc
From: Mukesh Kumar Chaurasiya <hidden>
Date: 2026-01-06 05:02:55
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On Thu, Jan 01, 2026 at 02:37:41PM +0530, Shrikanth Hegde wrote:
On 12/29/25 10:24 AM, Mukesh Kumar Chaurasiya wrote:quoted
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 | Syscall | Base | New | change % | | ------- | ---------- | ---------- | -------- | | basic | 0.173212 | 0.133294 | -23.05 | | execve | 363.176190 | 357.148150 | -1.66 | | fork | 853.657880 | 840.268800 | -1.57 | | getpgid | 0.174832 | 0.135372 | -22.57 |Could you please add a description for whether its an improvement or regression. Looking at it, it seems time taken for operation to complete. So it is an improvement. Seeing negative numbers one might think its a regression.
Sure will add an explanation.
Also, are these average numbers?
Yes, as there was very high run to run variation i took an avg of 100 runs.
Could you get the numbers with preempt=lazy and with context tracking on?
Sure will do those too. Regards, Mukesh
quoted
perf bench syscall ops/sec | Syscall | Base | New | change % | | ------- | ------- | ------- | -------- | | basic | 6006021 | 7502236 | +24.91 | | execve | 2753 | 2800 | +1.71 | | fork | 1171 | 1190 | +1.62 | | getpgid | 5942117 | 7387040 | +24.32 | IPI latency benchmark | Metric | Base (ns) | Test (ns) | change % | | -------------- | ------------- | ------------- | -------- | | Dry-run | 206652.45 | 209317.37 | +1.29 | | Self-IPI | 3567895.23 | 3590444.77 | +0.63 | | Normal IPI | 148570416.17 | 148564173.40 | -0.00 | | Broadcast IPI | 4033489673.38 | 4007319512.62 | -0.65 | | Broadcast lock | 4011023005.48 | 4010267885.93 | -0.02 |