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| author | Vincent Zhang <xunz@nvidia.com> | 2019-05-28 10:51:03 +0800 |
|---|---|---|
| committer | Yabin Cui <yabinc@google.com> | 2019-06-25 11:13:03 -0700 |
| commit | 758c2ddabbd68af14880f84b375a5819c52c7968 (patch) | |
| tree | a2201a5d1182123270bd6891a6e25fe3e9b68bae | |
| parent | 429c4770daf538112ba0424b919450e5e1228754 (diff) | |
| download | extras-758c2ddabbd68af14880f84b375a5819c52c7968.tar.gz | |
simpleperf: Add bottom up memory layout support
There are chances that instead of allocating a vma on every mmap() call,
an existing vma gets chosen and expanded.
On system that using legacy memory layout(mmap grows bottom up), vma_merge()
updates the vm_end instead of vm_start in the chosen vma, which results
in a false mismatch (record.data->addr == thread_arg.mmap_start_addr) in
GetClockDiff().
To make simpleperf compatible with bottom up memory layout, we need to
force vma allocation on mmap() calls, one approach is by assigning name to
each anonymous mmap region.
Bug: 136012903
Test: run CtsSimpleperfTestCases.
Change-Id: I4c833105d9921a5db1493c60fcf6d06eb2cd3a96
| -rw-r--r-- | simpleperf/environment.h | 6 | ||||
| -rw-r--r-- | simpleperf/perf_clock.cpp | 4 |
2 files changed, 10 insertions, 0 deletions
diff --git a/simpleperf/environment.h b/simpleperf/environment.h index 7f8683de..8886e470 100644 --- a/simpleperf/environment.h +++ b/simpleperf/environment.h @@ -23,6 +23,7 @@ #if defined(__linux__) #include <sys/syscall.h> #include <unistd.h> +#include <sys/prctl.h> #endif #include <functional> @@ -35,6 +36,11 @@ #include "build_id.h" #include "perf_regs.h" +#if defined(__ANDROID__) + #define PR_SET_VMA 0x53564d41 + #define PR_SET_VMA_ANON_NAME 0 +#endif + std::vector<int> GetOnlineCpus(); std::vector<int> GetCpusFromString(const std::string& s); diff --git a/simpleperf/perf_clock.cpp b/simpleperf/perf_clock.cpp index 127470e7..127fd21d 100644 --- a/simpleperf/perf_clock.cpp +++ b/simpleperf/perf_clock.cpp @@ -70,6 +70,10 @@ static void ThreadA(ThreadArg* thread_arg) { } array[i].end_system_time_in_ns = GetSystemClock(); + +#if defined(__ANDROID__) + prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, array[i].mmap_start_addr, 4096, "anony_map_region"); +#endif } size_t best_index = 0; uint64_t min_duration_in_ns = UINT64_MAX; |