[compiler-rt] r320594 - [sanitizer] Introduce a vDSO aware timing function

Krzysztof Parzyszek via llvm-commits llvm-commits at lists.llvm.org
Sat Dec 16 09:51:34 PST 2017


This broke FreeBSD build:

In file included from 
/w/src/llvm.org/projects/compiler-rt/lib/lsan/lsan_common.cc:15:
In file included from 
/w/src/llvm.org/projects/compiler-rt/lib/lsan/lsan_common.h:18:
In file included from 
/w/src/llvm.org/projects/compiler-rt/lib/lsan/../sanitizer_common/sanitizer_allocator.h:23:
In file included from 
/w/src/llvm.org/projects/compiler-rt/lib/lsan/../sanitizer_common/sanitizer_procmaps.h:23:
/w/src/llvm.org/projects/compiler-rt/lib/lsan/../sanitizer_common/sanitizer_linux.h:49:29: 
error: unknown type name '__sanitizer_clockid_t'; did you mean 
'__sanitizer_clock_t'?
uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp);
                             ^~~~~~~~~~~~~~~~~~~~~
                             __sanitizer_clock_t
/w/src/llvm.org/projects/compiler-rt/lib/lsan/../sanitizer_common/sanitizer_platform_limits_posix.h:530:15: 
note: '__sanitizer_clock_t' declared here
   typedef int __sanitizer_clock_t;
               ^

-Krzysztof


On 12/13/2017 10:23 AM, Kostya Kortchinsky via llvm-commits wrote:
> Author: cryptoad
> Date: Wed Dec 13 08:23:54 2017
> New Revision: 320594
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=320594&view=rev
> Log:
> [sanitizer] Introduce a vDSO aware timing function
> 
> Summary:
> See D40657 & D40679 for previous versions of this patch & description.
> 
> A couple of things were fixed here to have it not break some bots.
> Weak symbols can't be used with `SANITIZER_GO` so the previous version was
> breakin TsanGo. I set up some additional local tests and those pass now.
> 
> I changed the workaround for the glibc vDSO issue: `__progname` is initialized
> after the vDSO and is actually public and of known type, unlike
> `__vdso_clock_gettime`. This works better, and with all compilers.
> 
> The rest is the same.
> 
> Reviewers: alekseyshl
> 
> Reviewed By: alekseyshl
> 
> Subscribers: srhines, kubamracek, krytarowski, llvm-commits, #sanitizers
> 
> Differential Revision: https://reviews.llvm.org/D41121
> 
> Modified:
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_allocator_primary64.h
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.h
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_syscall_generic.inc
>      compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
>      compiler-rt/trunk/lib/scudo/scudo_allocator.cpp
>      compiler-rt/trunk/lib/scudo/scudo_tsd.h
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_allocator_primary64.h
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_allocator_primary64.h?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_allocator_primary64.h (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_allocator_primary64.h Wed Dec 13 08:23:54 2017
> @@ -697,7 +697,7 @@ class SizeClassAllocator64 {
>           // Do it only when the feature is turned on, to avoid a potentially
>           // extraneous syscall.
>           if (ReleaseToOSIntervalMs() >= 0)
> -          region->rtoi.last_release_at_ns = NanoTime();
> +          region->rtoi.last_release_at_ns = MonotonicNanoTime();
>         }
>         // Do the mmap for the user memory.
>         const uptr user_map_size =
> @@ -827,7 +827,7 @@ class SizeClassAllocator64 {
>           return;
>   
>         if (region->rtoi.last_release_at_ns + interval_ms * 1000000ULL >
> -          NanoTime()) {
> +          MonotonicNanoTime()) {
>           return;  // Memory was returned recently.
>         }
>       }
> @@ -844,6 +844,6 @@ class SizeClassAllocator64 {
>         region->rtoi.num_releases += memory_mapper.GetReleasedRangesCount();
>         region->rtoi.last_released_bytes = memory_mapper.GetReleasedBytes();
>       }
> -    region->rtoi.last_release_at_ns = NanoTime();
> +    region->rtoi.last_release_at_ns = MonotonicNanoTime();
>     }
>   };
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h Wed Dec 13 08:23:54 2017
> @@ -295,6 +295,7 @@ uptr GetTlsSize();
>   void SleepForSeconds(int seconds);
>   void SleepForMillis(int millis);
>   u64 NanoTime();
> +u64 MonotonicNanoTime();
>   int Atexit(void (*function)(void));
>   void SortArray(uptr *array, uptr size);
>   void SortArray(u32 *array, uptr size);
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc Wed Dec 13 08:23:54 2017
> @@ -2045,6 +2045,13 @@ INTERCEPTOR(int, clock_gettime, u32 clk_
>     }
>     return res;
>   }
> +namespace __sanitizer {
> +extern "C" {
> +int real_clock_gettime(u32 clk_id, void *tp) {
> +  return REAL(clock_gettime)(clk_id, tp);
> +}
> +}  // extern "C"
> +}  // namespace __sanitizer
>   INTERCEPTOR(int, clock_settime, u32 clk_id, const void *tp) {
>     void *ctx;
>     COMMON_INTERCEPTOR_ENTER(ctx, clock_settime, clk_id, tp);
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc Wed Dec 13 08:23:54 2017
> @@ -51,6 +51,8 @@ unsigned int internal_sleep(unsigned int
>   
>   u64 NanoTime() { return _zx_time_get(ZX_CLOCK_UTC); }
>   
> +u64 MonotonicNanoTime() { return _zx_time_get(ZX_CLOCK_MONOTONIC); }
> +
>   uptr internal_getpid() {
>     zx_info_handle_basic_t info;
>     zx_status_t status =
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc Wed Dec 13 08:23:54 2017
> @@ -459,6 +459,10 @@ u64 NanoTime() {
>     return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
>   }
>   
> +uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) {
> +  return internal_syscall_ptr(SYSCALL(clock_gettime), clk_id, tp);
> +}
> +
>   // Like getenv, but reads env directly from /proc (on Linux) or parses the
>   // 'environ' array (on FreeBSD) and does not use libc. This function should be
>   // called first inside __asan_init.
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.h
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.h?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.h (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.h Wed Dec 13 08:23:54 2017
> @@ -46,6 +46,7 @@ uptr internal_getdents(fd_t fd, struct l
>   uptr internal_sigaltstack(const void* ss, void* oss);
>   uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
>       __sanitizer_sigset_t *oldset);
> +uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp);
>   
>   // Linux-only syscalls.
>   #if SANITIZER_LINUX
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc Wed Dec 13 08:23:54 2017
> @@ -707,6 +707,47 @@ void LogMessageOnPrintf(const char *str)
>   
>   #endif  // SANITIZER_LINUX
>   
> +#if SANITIZER_LINUX && !SANITIZER_GO
> +// glibc crashes when using clock_gettime from a preinit_array function as the
> +// vDSO function pointers haven't been initialized yet. __progname is
> +// initialized after the vDSO function pointers, so if it exists, is not null
> +// and is not empty, we can use clock_gettime.
> +extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname;
> +INLINE bool CanUseVDSO() {
> +  // Bionic is safe, it checks for the vDSO function pointers to be initialized.
> +  if (SANITIZER_ANDROID)
> +    return true;
> +  if (&__progname && __progname && *__progname)
> +    return true;
> +  return false;
> +}
> +
> +// MonotonicNanoTime is a timing function that can leverage the vDSO by calling
> +// clock_gettime. real_clock_gettime only exists if clock_gettime is
> +// intercepted, so define it weakly and use it if available.
> +extern "C" SANITIZER_WEAK_ATTRIBUTE
> +int real_clock_gettime(u32 clk_id, void *tp);
> +u64 MonotonicNanoTime() {
> +  timespec ts;
> +  if (CanUseVDSO()) {
> +    if (&real_clock_gettime)
> +      real_clock_gettime(CLOCK_MONOTONIC, &ts);
> +    else
> +      clock_gettime(CLOCK_MONOTONIC, &ts);
> +  } else {
> +    internal_clock_gettime(CLOCK_MONOTONIC, &ts);
> +  }
> +  return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
> +}
> +#else
> +// Non-Linux & Go always use the syscall.
> +u64 MonotonicNanoTime() {
> +  timespec ts;
> +  internal_clock_gettime(CLOCK_MONOTONIC, &ts);
> +  return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
> +}
> +#endif  // SANITIZER_LINUX && !SANITIZER_GO
> +
>   } // namespace __sanitizer
>   
> -#endif // SANITIZER_FREEBSD || SANITIZER_LINUX
> +#endif  // SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc Wed Dec 13 08:23:54 2017
> @@ -365,6 +365,10 @@ u64 NanoTime() {
>     return 0;
>   }
>   
> +u64 MonotonicNanoTime() {
> +  return 0;
> +}
> +
>   uptr GetTlsSize() {
>     return 0;
>   }
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_syscall_generic.inc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_syscall_generic.inc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_syscall_generic.inc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_syscall_generic.inc Wed Dec 13 08:23:54 2017
> @@ -36,6 +36,7 @@
>   # define SYS_sigaltstack SYS___sigaltstack14
>   # define SYS_sigprocmask SYS___sigprocmask14
>   # define SYS_nanosleep SYS___nanosleep50
> +# define SYS_clock_gettime SYS___clock_gettime50
>   # if SANITIZER_WORDSIZE == 64
>   #  define internal_syscall_ptr  __syscall
>   # else
> 
> Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc (original)
> +++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc Wed Dec 13 08:23:54 2017
> @@ -505,6 +505,10 @@ u64 NanoTime() {
>     return 0;
>   }
>   
> +u64 MonotonicNanoTime() {
> +  return 0;
> +}
> +
>   void Abort() {
>     internal__exit(3);
>   }
> 
> Modified: compiler-rt/trunk/lib/scudo/scudo_allocator.cpp
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/scudo/scudo_allocator.cpp?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/scudo/scudo_allocator.cpp (original)
> +++ compiler-rt/trunk/lib/scudo/scudo_allocator.cpp Wed Dec 13 08:23:54 2017
> @@ -301,7 +301,7 @@ struct ScudoAllocator {
>   
>       CheckRssLimit = HardRssLimitMb || SoftRssLimitMb;
>       if (CheckRssLimit)
> -      atomic_store_relaxed(&RssLastCheckedAtNS, NanoTime());
> +      atomic_store_relaxed(&RssLastCheckedAtNS, MonotonicNanoTime());
>     }
>   
>     // Helper function that checks for a valid Scudo chunk. nullptr isn't.
> @@ -319,7 +319,7 @@ struct ScudoAllocator {
>     // it can, every 100ms, otherwise it will just return the current one.
>     bool isRssLimitExceeded() {
>       u64 LastCheck = atomic_load_relaxed(&RssLastCheckedAtNS);
> -    const u64 CurrentCheck = NanoTime();
> +    const u64 CurrentCheck = MonotonicNanoTime();
>       if (LIKELY(CurrentCheck < LastCheck + (100ULL * 1000000ULL)))
>         return atomic_load_relaxed(&RssLimitExceeded);
>       if (!atomic_compare_exchange_weak(&RssLastCheckedAtNS, &LastCheck,
> 
> Modified: compiler-rt/trunk/lib/scudo/scudo_tsd.h
> URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/scudo/scudo_tsd.h?rev=320594&r1=320593&r2=320594&view=diff
> ==============================================================================
> --- compiler-rt/trunk/lib/scudo/scudo_tsd.h (original)
> +++ compiler-rt/trunk/lib/scudo/scudo_tsd.h Wed Dec 13 08:23:54 2017
> @@ -36,7 +36,7 @@ struct ALIGNED(64) ScudoTSD {
>         return true;
>       }
>       if (atomic_load_relaxed(&Precedence) == 0)
> -      atomic_store_relaxed(&Precedence, NanoTime());
> +      atomic_store_relaxed(&Precedence, MonotonicNanoTime());
>       return false;
>     }
>   
> 
> 
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
> 
> 
> ---
> This email has been checked for viruses by AVG.
> http://www.avg.com
> 



More information about the llvm-commits mailing list