mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-16 07:24:39 +08:00
c22497f583
Adaptive PEBS is a new way to report PEBS sampling information. Instead of a fixed size record for all PEBS events it allows to configure the PEBS record to only include the information needed. Events can then opt in to use such an extended record, or stay with a basic record which only contains the IP. The major new feature is to support LBRs in PEBS record. Besides normal LBR, this allows (much faster) large PEBS, while still supporting callstacks through callstack LBR. So essentially a lot of profiling can now be done without frequent interrupts, dropping the overhead significantly. The main requirement still is to use a period, and not use frequency mode, because frequency mode requires reevaluating the frequency on each overflow. The floating point state (XMM) is also supported, which allows efficient profiling of FP function arguments. Introduce specific drain function to handle variable length records. Use a new callback to parse the new record format, and also handle the STATUS field now being at a different offset. Add code to set up the configuration register. Since there is only a single register, all events either get the full super set of all events, or only the basic record. Originally-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-6-kan.liang@linux.intel.com [ Renamed GPRS => GP. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|---|---|---|
| .. | ||
| amd | ||
| intel | ||
| core.c | ||
| Kconfig | ||
| Makefile | ||
| msr.c | ||
| perf_event.h | ||