Author: Walter Erquinigo Date: 2022-06-15T12:07:59-07:00 New Revision: 5a92632dc477fcd42d912b2c781cc406e6d073f6
URL: https://github.com/llvm/llvm-project/commit/5a92632dc477fcd42d912b2c781cc406e6d073f6 DIFF: https://github.com/llvm/llvm-project/commit/5a92632dc477fcd42d912b2c781cc406e6d073f6.diff LOG: [trace][intelpt] Support system-wide tracing [8] - Improve the single buffer perf_event configuration We were setting some events to be written in the data buffer of the perf_event, but we don't need that. Besides that, we don't need the data buffer to be larger than 1, so we can reduce its size. Differential Revision: https://reviews.llvm.org/D125850 Added: Modified: lldb/source/Plugins/Process/Linux/IntelPTSingleBufferTrace.cpp Removed: ################################################################################ diff --git a/lldb/source/Plugins/Process/Linux/IntelPTSingleBufferTrace.cpp b/lldb/source/Plugins/Process/Linux/IntelPTSingleBufferTrace.cpp index 047ce471149f..a587b5826af2 100644 --- a/lldb/source/Plugins/Process/Linux/IntelPTSingleBufferTrace.cpp +++ b/lldb/source/Plugins/Process/Linux/IntelPTSingleBufferTrace.cpp @@ -183,11 +183,8 @@ CreateIntelPTPerfEventConfiguration(bool enable_tsc, memset(&attr, 0, sizeof(attr)); attr.size = sizeof(attr); attr.exclude_kernel = 1; - attr.sample_type = PERF_SAMPLE_TIME; - attr.sample_id_all = 1; attr.exclude_hv = 1; attr.exclude_idle = 1; - attr.mmap = 1; if (Expected<uint64_t> config_value = GeneratePerfEventConfigValue(enable_tsc, psb_period)) @@ -297,7 +294,7 @@ Expected<IntelPTSingleBufferTraceUP> IntelPTSingleBufferTrace::Start( request.trace_buffer_size); } uint64_t page_size = getpagesize(); - uint64_t buffer_numpages = static_cast<uint64_t>(llvm::PowerOf2Floor( + uint64_t aux_buffer_numpages = static_cast<uint64_t>(llvm::PowerOf2Floor( (request.trace_buffer_size + page_size - 1) / page_size)); Expected<perf_event_attr> attr = CreateIntelPTPerfEventConfiguration( @@ -312,8 +309,8 @@ Expected<IntelPTSingleBufferTraceUP> IntelPTSingleBufferTrace::Start( request.trace_buffer_size); if (Expected<PerfEvent> perf_event = PerfEvent::Init(*attr, tid, core_id)) { - if (Error mmap_err = perf_event->MmapMetadataAndBuffers(buffer_numpages, - buffer_numpages)) { + if (Error mmap_err = perf_event->MmapMetadataAndBuffers( + /*num_data_pages=*/0, aux_buffer_numpages)) { return std::move(mmap_err); } IntelPTSingleBufferTraceUP trace_up( _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
