[compiler-rt] r177629 - tsan: flush symbolizer cache if not symbolized for more than 5 seconds

[Alexander Potapenko]

I suggest to make the constant changeable from the command line (and
perhaps include the option to disable this behavior). You know that
better than me that hardcoded constants are evil :)
I also suggest to make 1000 * 1000 a constant (e.g. kMillisecondsInSecond).
Also, please put spaces around the "*" operator.

On Thu, Mar 21, 2013 at 11:02 AM, Dmitry Vyukov <dvyukov at google.com> wrote:
> Author: dvyukov
> Date: Thu Mar 21 02:02:36 2013
> New Revision: 177629
>
> URL: http://llvm.org/viewvc/llvm-project?rev=177629&view=rev
> Log:
> tsan: flush symbolizer cache if not symbolized for more than 5 seconds
>
>
> Modified:
>     compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc
>     compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.h
>     compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_report.cc
>
> Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc?rev=177629&r1=177628&r2=177629&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc (original)
> +++ compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc Thu Mar 21 02:02:36 2013
> @@ -23,6 +23,7 @@
>  #include "tsan_rtl.h"
>  #include "tsan_mman.h"
>  #include "tsan_suppressions.h"
> +#include "tsan_symbolize.h"
>
>  volatile int __tsan_resumed = 0;
>
> @@ -95,12 +96,11 @@ ThreadState::ThreadState(Context *ctx, i
>    , tls_size(tls_size) {
>  }
>
> -static void MemoryProfiler(int i, fd_t fd) {
> -  Context *ctx = CTX();
> -  InternalScopedBuffer<char> buf(4096);
> +static void MemoryProfiler(Context *ctx, fd_t fd, int i) {
>    uptr n_threads;
>    uptr n_running_threads;
>    ctx->thread_registry->GetNumberOfThreads(&n_threads, &n_running_threads);
> +  InternalScopedBuffer<char> buf(4096);
>    internal_snprintf(buf.data(), buf.size(), "%d: nthr=%d nlive=%d\n",
>        i, n_threads, n_running_threads);
>    internal_write(fd, buf.data(), internal_strlen(buf.data()));
> @@ -110,6 +110,7 @@ static void MemoryProfiler(int i, fd_t f
>
>  static void BackgroundThread(void *arg) {
>    ScopedInRtl in_rtl;
> +  Context *ctx = CTX();
>
>    fd_t mprof_fd = kInvalidFd;
>    if (flags()->profile_memory && flags()->profile_memory[0]) {
> @@ -128,6 +129,7 @@ static void BackgroundThread(void *arg)
>      SleepForSeconds(1);
>      u64 now = NanoTime();
>
> +    // Flush memory if requested.
>      if (flags()->flush_memory_ms) {
>        if (last_flush + flags()->flush_memory_ms * 1000*1000 > now) {
>          FlushShadowMemory();
> @@ -135,8 +137,19 @@ static void BackgroundThread(void *arg)
>        }
>      }
>
> +    // Write memory profile if requested.
>      if (mprof_fd != kInvalidFd)
> -      MemoryProfiler(i, mprof_fd);
> +      MemoryProfiler(ctx, mprof_fd, i);
> +
> +#ifndef TSAN_GO
> +    // Flush symbolizer cache if not symbolized for more than 5 seconds.
> +    u64 last = atomic_load(&ctx->last_symbolize_time_ns, memory_order_relaxed);
> +    if (last != 0 && last + 5*1000*1000 > now) {
> +      Lock l(&ctx->report_mtx);
> +      SymbolizeFlush();
> +      atomic_store(&ctx->last_symbolize_time_ns, 0, memory_order_relaxed);
> +    }
> +#endif
>    }
>  }
>
>
> Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.h
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.h?rev=177629&r1=177628&r2=177629&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.h (original)
> +++ compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.h Thu Mar 21 02:02:36 2013
> @@ -516,6 +516,7 @@ struct Context {
>    Mutex report_mtx;
>    int nreported;
>    int nmissed_expected;
> +  atomic_uint64_t last_symbolize_time_ns;
>
>    ThreadRegistry *thread_registry;
>
>
> Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_report.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_report.cc?rev=177629&r1=177628&r2=177629&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_report.cc (original)
> +++ compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_report.cc Thu Mar 21 02:02:36 2013
> @@ -495,6 +495,7 @@ bool OutputReport(Context *ctx,
>                    const ScopedReport &srep,
>                    const ReportStack *suppress_stack1,
>                    const ReportStack *suppress_stack2) {
> +  atomic_store(&ctx->last_symbolize_time_ns, NanoTime(), memory_order_relaxed);
>    const ReportDesc *rep = srep.GetReport();
>    uptr suppress_pc = IsSuppressed(rep->typ, suppress_stack1);
>    if (suppress_pc == 0)
>
>
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits



-- 
Alexander Potapenko
Software Engineer
Google Moscow