On Mon, Oct 14, 2024 at 11:11 AM Yafang Shao <laoar.shao@xxxxxxxxx> wrote: > > After enabling CONFIG_IRQ_TIME_ACCOUNTING to track IRQ pressure in our > container environment, we encountered several user-visible behavioral > changes: > > - Interrupted IRQ/softirq time is not accounted for in the cpuacct cgroup > > This breaks userspace applications that rely on CPU usage data from > cgroups to monitor CPU pressure. This patchset resolves the issue by > ensuring that IRQ/softirq time is accounted for in the cgroup of the > interrupted tasks. > > - getrusage(2) does not include time interrupted by IRQ/softirq > > Some services use getrusage(2) to check if workloads are experiencing CPU > pressure. Since IRQ/softirq time is no longer charged to task runtime, > getrusage(2) can no longer reflect the CPU pressure caused by heavy > interrupts. > > This patchset addresses the first issue, which is relatively > straightforward. However, the second issue remains unresolved, as there > might be debate over whether interrupted time should be considered part of > a task’s usage. Nonetheless, it is important to report interrupted time to > the user via some metric, though that is a separate discussion. > > Changes: > v2->v3: > - Add a helper account_irqtime() to avoid redundant code (Johannes) > > v1->v2: https://lore.kernel.org/cgroups/20241008061951.3980-1-laoar.shao@xxxxxxxxx/ > - Fix lockdep issues reported by kernel test robot <oliver.sang@xxxxxxxxx> > > v1: https://lore.kernel.org/all/20240923090028.16368-1-laoar.shao@xxxxxxxxx/ > > Yafang Shao (4): > sched: Define sched_clock_irqtime as static key > sched: Don't account irq time if sched_clock_irqtime is disabled > sched, psi: Don't account irq time if sched_clock_irqtime is disabled > sched: Fix cgroup irq accounting for CONFIG_IRQ_TIME_ACCOUNTING > > kernel/sched/core.c | 78 +++++++++++++++++++++++++++++------------- > kernel/sched/cputime.c | 16 ++++----- > kernel/sched/psi.c | 12 ++----- > kernel/sched/sched.h | 1 + > kernel/sched/stats.h | 7 ++-- > 5 files changed, 69 insertions(+), 45 deletions(-) > > -- > 2.43.5 > Hello Peter, Hello Ingo, Do you have comments or any suggestions on this fix? -- Regards Yafang
