diff options
| author | Leonardo Bras <leobras@redhat.com> | 2023-06-15 03:59:45 -0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-06-16 22:08:09 +0200 |
| commit | 949fa3f11ced2a5c8e3737e73b09676adf4b322b (patch) | |
| tree | 280e923f561dadfad15c4fc564adf56dc93ec58a /include/trace | |
| parent | 60be49bdf1d4ddb9e2deb7aa718d5b8bc167ee4e (diff) | |
trace,smp: Add tracepoints around remotelly called functions
The recently added ipi_send_{cpu,cpumask} tracepoints allow finding sources
of IPIs targeting CPUs running latency-sensitive applications.
For NOHZ_FULL CPUs, all IPIs are interference, and those tracepoints are
sufficient to find them and work on getting rid of them. In some setups
however, not *all* IPIs are to be suppressed, but long-running IPI
callbacks can still be problematic.
Add a pair of tracepoints to mark the start and end of processing a CSD IPI
callback, similar to what exists for softirq, workqueue or timer callbacks.
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Tested-and-reviewed-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230615065944.188876-5-leobras@redhat.com
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/csd.h | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/include/trace/events/csd.h b/include/trace/events/csd.h new file mode 100644 index 000000000000..af1df5200ae6 --- /dev/null +++ b/include/trace/events/csd.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM csd + +#if !defined(_TRACE_CSD_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_CSD_H + +#include <linux/tracepoint.h> + +/* + * Tracepoints for a function which is called as an effect of smp_call_function.* + */ +DECLARE_EVENT_CLASS(csd_function, + + TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + + TP_ARGS(func, csd), + + TP_STRUCT__entry( + __field(void *, func) + __field(void *, csd) + ), + + TP_fast_assign( + __entry->func = func; + __entry->csd = csd; + ), + + TP_printk("func=%ps, csd=%p", __entry->func, __entry->csd) +); + +DEFINE_EVENT(csd_function, csd_function_entry, + TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + TP_ARGS(func, csd) +); + +DEFINE_EVENT(csd_function, csd_function_exit, + TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + TP_ARGS(func, csd) +); + +#endif /* _TRACE_CSD_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> |