DavidSpickett created this revision.
Herald added a project: All.
DavidSpickett requested review of this revision.
Herald added a project: LLDB.
Herald added a subscriber: lldb-commits.
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D133763
Files:
lldb/source/Plugins/Process/Linux/Perf.cpp
lldb/source/Plugins/Process/Linux/Perf.h
Index: lldb/source/Plugins/Process/Linux/Perf.h
===================================================================
--- lldb/source/Plugins/Process/Linux/Perf.h
+++ lldb/source/Plugins/Process/Linux/Perf.h
@@ -22,6 +22,21 @@
#include <cstdint>
#include <linux/perf_event.h>
+struct perf_event_mmap_page_custom {
+ int cap_user_time;
+ int cap_user_time_zero;
+ uint32_t time_mult;
+ uint16_t time_shift;
+ uint64_t time_zero;
+
+ //uint64_t aux_head;
+ //int aux_offset;
+ //unsigned long aux_size;
+ //uint64_t data_head;
+ //int data_offset;
+ //unsigned long data_size;
+};
+
namespace lldb_private {
namespace process_linux {
namespace resource_handle {
@@ -142,7 +157,7 @@
/// \param[in] num_data_pages
/// Number of pages in the data buffer to mmap, must be a power of 2.
/// A value of 0 is useful for "dummy" events that only want to access
- /// the metadata, \a perf_event_mmap_page, or the aux buffer.
+ /// the metadata, \a perf_event_mmap_page_custom, or the aux buffer.
///
/// \param[in] num_aux_pages
/// Number of pages in the aux buffer to mmap, must be a power of 2.
@@ -171,8 +186,8 @@
/// otherwise a failure might happen.
///
/// \return
- /// The data section's \a perf_event_mmap_page.
- perf_event_mmap_page &GetMetadataPage() const;
+ /// The data section's \a perf_event_mmap_page_custom.
+ perf_event_mmap_page_custom &GetMetadataPage() const;
/// Get the data buffer from the data section's mmap buffer.
///
@@ -278,7 +293,7 @@
/// \param[in] num_data_pages
/// Number of pages in the data buffer to mmap, must be a power of 2.
/// A value of 0 is useful for "dummy" events that only want to access
- /// the metadata, \a perf_event_mmap_page, or the aux buffer.
+ /// the metadata, \a perf_event_mmap_page_custom, or the aux buffer.
///
/// \param[in] data_buffer_write
/// Whether to mmap the data buffer with WRITE permissions. This changes
@@ -317,7 +332,7 @@
CreateContextSwitchTracePerfEvent(lldb::cpu_id_t cpu_id,
const PerfEvent *parent_perf_event = nullptr);
-/// Load \a PerfTscConversionParameters from \a perf_event_mmap_page, if
+/// Load \a PerfTscConversionParameters from \a perf_event_mmap_page_custom, if
/// available.
llvm::Expected<LinuxPerfZeroTscConversion> LoadPerfTscConversionParameters();
Index: lldb/source/Plugins/Process/Linux/Perf.cpp
===================================================================
--- lldb/source/Plugins/Process/Linux/Perf.cpp
+++ lldb/source/Plugins/Process/Linux/Perf.cpp
@@ -42,7 +42,7 @@
/*data_buffer_write=*/false))
return std::move(mmap_err);
- perf_event_mmap_page &mmap_metada = perf_event->GetMetadataPage();
+ perf_event_mmap_page_custom &mmap_metada = perf_event->GetMetadataPage();
if (mmap_metada.cap_user_time && mmap_metada.cap_user_time_zero) {
return LinuxPerfZeroTscConversion{
mmap_metada.time_mult, mmap_metada.time_shift, {mmap_metada.time_zero}};
@@ -128,19 +128,22 @@
if (num_aux_pages == 0)
return Error::success();
- perf_event_mmap_page &metadata_page = GetMetadataPage();
+ return llvm::createStringError(
+ llvm::inconvertibleErrorCode(), "foo");
- metadata_page.aux_offset =
- metadata_page.data_offset + metadata_page.data_size;
- metadata_page.aux_size = num_aux_pages * getpagesize();
-
- if (Expected<resource_handle::MmapUP> mmap_aux =
- DoMmap(nullptr, metadata_page.aux_size, PROT_READ, MAP_SHARED,
- metadata_page.aux_offset, "aux buffer")) {
- m_aux_base = std::move(mmap_aux.get());
- return Error::success();
- } else
- return mmap_aux.takeError();
+// perf_event_mmap_page_custom &metadata_page = GetMetadataPage();
+//
+// metadata_page.aux_offset =
+// metadata_page.data_offset + metadata_page.data_size;
+// metadata_page.aux_size = num_aux_pages * getpagesize();
+//
+// if (Expected<resource_handle::MmapUP> mmap_aux =
+// DoMmap(nullptr, metadata_page.aux_size, PROT_READ, MAP_SHARED,
+// metadata_page.aux_offset, "aux buffer")) {
+// m_aux_base = std::move(mmap_aux.get());
+// return Error::success();
+// } else
+// return mmap_aux.takeError();
}
llvm::Error PerfEvent::MmapMetadataAndBuffers(size_t num_data_pages,
@@ -165,21 +168,24 @@
long PerfEvent::GetFd() const { return *(m_fd.get()); }
-perf_event_mmap_page &PerfEvent::GetMetadataPage() const {
- return *reinterpret_cast<perf_event_mmap_page *>(m_metadata_data_base.get());
+perf_event_mmap_page_custom &PerfEvent::GetMetadataPage() const {
+ return *reinterpret_cast<perf_event_mmap_page_custom *>(m_metadata_data_base.get());
}
ArrayRef<uint8_t> PerfEvent::GetDataBuffer() const {
- perf_event_mmap_page &mmap_metadata = GetMetadataPage();
- return {reinterpret_cast<uint8_t *>(m_metadata_data_base.get()) +
- mmap_metadata.data_offset,
- static_cast<size_t>(mmap_metadata.data_size)};
+ // TODO: assert that this isn't called!
+ return {};
+// perf_event_mmap_page_custom &mmap_metadata = GetMetadataPage();
+// return {reinterpret_cast<uint8_t *>(m_metadata_data_base.get()) +
+// mmap_metadata.data_offset,
+// static_cast<size_t>(mmap_metadata.data_size)};
}
ArrayRef<uint8_t> PerfEvent::GetAuxBuffer() const {
- perf_event_mmap_page &mmap_metadata = GetMetadataPage();
- return {reinterpret_cast<uint8_t *>(m_aux_base.get()),
- static_cast<size_t>(mmap_metadata.aux_size)};
+ return {};
+// perf_event_mmap_page_custom &mmap_metadata = GetMetadataPage();
+// return {reinterpret_cast<uint8_t *>(m_aux_base.get()),
+// static_cast<size_t>(mmap_metadata.aux_size)};
}
Expected<std::vector<uint8_t>> PerfEvent::GetReadOnlyDataBuffer() {
@@ -188,7 +194,7 @@
// this piece of code updates some pointers. See more about data_tail
// in https://man7.org/linux/man-pages/man2/perf_event_open.2.html.
- bool was_enabled = m_enabled;
+ //bool was_enabled = m_enabled;
if (Error err = DisableWithIoctl())
return std::move(err);
@@ -199,31 +205,33 @@
* and we don't need to care about it, whereas the data_head keeps
* increasing and needs to be wrapped by modulus operator
*/
- perf_event_mmap_page &mmap_metadata = GetMetadataPage();
-
- ArrayRef<uint8_t> data = GetDataBuffer();
- uint64_t data_head = mmap_metadata.data_head;
- uint64_t data_size = mmap_metadata.data_size;
- std::vector<uint8_t> output;
- output.reserve(data.size());
-
- if (data_head > data_size) {
- uint64_t actual_data_head = data_head % data_size;
- // The buffer has wrapped, so we first the oldest chunk of data
- output.insert(output.end(), data.begin() + actual_data_head, data.end());
- // And we we read the most recent chunk of data
- output.insert(output.end(), data.begin(), data.begin() + actual_data_head);
- } else {
- // There's been no wrapping, so we just read linearly
- output.insert(output.end(), data.begin(), data.begin() + data_head);
- }
-
- if (was_enabled) {
- if (Error err = EnableWithIoctl())
- return std::move(err);
- }
-
- return output;
+ return llvm::createStringError(
+ llvm::inconvertibleErrorCode(), "foo");
+// perf_event_mmap_page_custom &mmap_metadata = GetMetadataPage();
+//
+// ArrayRef<uint8_t> data = GetDataBuffer();
+// uint64_t data_head = mmap_metadata.data_head;
+// uint64_t data_size = mmap_metadata.data_size;
+// std::vector<uint8_t> output;
+// output.reserve(data.size());
+//
+// if (data_head > data_size) {
+// uint64_t actual_data_head = data_head % data_size;
+// // The buffer has wrapped, so we first the oldest chunk of data
+// output.insert(output.end(), data.begin() + actual_data_head, data.end());
+// // And we we read the most recent chunk of data
+// output.insert(output.end(), data.begin(), data.begin() + actual_data_head);
+// } else {
+// // There's been no wrapping, so we just read linearly
+// output.insert(output.end(), data.begin(), data.begin() + data_head);
+// }
+//
+// if (was_enabled) {
+// if (Error err = EnableWithIoctl())
+// return std::move(err);
+// }
+//
+// return output;
}
Expected<std::vector<uint8_t>> PerfEvent::GetReadOnlyAuxBuffer() {
@@ -232,38 +240,41 @@
// this piece of code updates some pointers. See more about aux_tail
// in https://man7.org/linux/man-pages/man2/perf_event_open.2.html.
- bool was_enabled = m_enabled;
+ //bool was_enabled = m_enabled;
if (Error err = DisableWithIoctl())
return std::move(err);
- perf_event_mmap_page &mmap_metadata = GetMetadataPage();
-
- ArrayRef<uint8_t> data = GetAuxBuffer();
- uint64_t aux_head = mmap_metadata.aux_head;
- std::vector<uint8_t> output;
- output.reserve(data.size());
-
- /**
- * When configured as ring buffer, the aux buffer keeps wrapping around
- * the buffer and its not possible to detect how many times the buffer
- * wrapped. Initially the buffer is filled with zeros,as shown below
- * so in order to get complete buffer we first copy firstpartsize, followed
- * by any left over part from beginning to aux_head
- *
- * aux_offset [d,d,d,d,d,d,d,d,0,0,0,0,0,0,0,0,0,0,0] aux_size
- * aux_head->||<- firstpartsize ->|
- *
- * */
-
- output.insert(output.end(), data.begin() + aux_head, data.end());
- output.insert(output.end(), data.begin(), data.begin() + aux_head);
-
- if (was_enabled) {
- if (Error err = EnableWithIoctl())
- return std::move(err);
- }
+ return llvm::createStringError(
+ llvm::inconvertibleErrorCode(), "foo");
- return output;
+// perf_event_mmap_page_custom &mmap_metadata = GetMetadataPage();
+//
+// ArrayRef<uint8_t> data = GetAuxBuffer();
+// uint64_t aux_head = mmap_metadata.aux_head;
+// std::vector<uint8_t> output;
+// output.reserve(data.size());
+//
+// /**
+// * When configured as ring buffer, the aux buffer keeps wrapping around
+// * the buffer and its not possible to detect how many times the buffer
+// * wrapped. Initially the buffer is filled with zeros,as shown below
+// * so in order to get complete buffer we first copy firstpartsize, followed
+// * by any left over part from beginning to aux_head
+// *
+// * aux_offset [d,d,d,d,d,d,d,d,0,0,0,0,0,0,0,0,0,0,0] aux_size
+// * aux_head->||<- firstpartsize ->|
+// *
+// * */
+//
+// output.insert(output.end(), data.begin() + aux_head, data.end());
+// output.insert(output.end(), data.begin(), data.begin() + aux_head);
+//
+// if (was_enabled) {
+// if (Error err = EnableWithIoctl())
+// return std::move(err);
+// }
+//
+// return output;
}
Error PerfEvent::DisableWithIoctl() {
@@ -295,11 +306,13 @@
}
size_t PerfEvent::GetEffectiveDataBufferSize() const {
- perf_event_mmap_page &mmap_metadata = GetMetadataPage();
- if (mmap_metadata.data_head < mmap_metadata.data_size)
- return mmap_metadata.data_head;
- else
- return mmap_metadata.data_size; // The buffer has wrapped.
+ // TODO: assert not called!
+ return 0;
+// perf_event_mmap_page_custom &mmap_metadata = GetMetadataPage();
+// if (mmap_metadata.data_head < mmap_metadata.data_size)
+// return mmap_metadata.data_head;
+// else
+// return mmap_metadata.data_size; // The buffer has wrapped.
}
Expected<PerfEvent>
_______________________________________________
lldb-commits mailing list
lldb-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
