mmapForContinuousMode: Align Linux's impl to __APPLE__'s more. NFC.

[chapuni]

No description provided.

[llvmbot]

@llvm/pr-subscribers-pgo

Author: NAKAMURA Takumi (chapuni)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/95702.diff

1 Files Affected:

• (modified) compiler-rt/lib/profile/InstrProfilingFile.c (+26-4)

diff --git a/compiler-rt/lib/profile/InstrProfilingFile.c b/compiler-rt/lib/profile/InstrProfilingFile.c
index b88e0b4b0b2ab..9faee36e5b815 100644
--- a/compiler-rt/lib/profile/InstrProfilingFile.c
+++ b/compiler-rt/lib/profile/InstrProfilingFile.c
@@ -237,24 +237,46 @@ static int mmapForContinuousMode(uint64_t CurrentFileOffset, FILE *File) {
   const char *CountersEnd = __llvm_profile_end_counters();
   const char *BitmapBegin = __llvm_profile_begin_bitmap();
   const char *BitmapEnd = __llvm_profile_end_bitmap();
+  const char *NamesBegin = __llvm_profile_begin_names();
+  const char *NamesEnd = __llvm_profile_end_names();
+  const uint64_t NamesSize = (NamesEnd - NamesBegin) * sizeof(char);
   uint64_t DataSize = __llvm_profile_get_data_size(DataBegin, DataEnd);
+  uint64_t CountersSize =
+      __llvm_profile_get_counters_size(CountersBegin, CountersEnd);
+  uint64_t NumBitmapBytes =
+      __llvm_profile_get_num_bitmap_bytes(BitmapBegin, BitmapEnd);
   /* Get the file size. */
   uint64_t FileSize = 0;
   if (getProfileFileSizeForMerging(File, &FileSize))
     return 1;
 
+  int Fileno = fileno(File);
+  /* Determine how much padding is needed before/after the counters and
+   * after the names. */
+  uint64_t PaddingBytesBeforeCounters, PaddingBytesAfterCounters,
+      PaddingBytesAfterNames, PaddingBytesAfterBitmapBytes,
+      PaddingBytesAfterVTable, PaddingBytesAfterVNames;
+  __llvm_profile_get_padding_sizes_for_counters(
+      DataSize, CountersSize, NumBitmapBytes, NamesSize, /*VTableSize=*/0,
+      /*VNameSize=*/0, &PaddingBytesBeforeCounters, &PaddingBytesAfterCounters,
+      &PaddingBytesAfterBitmapBytes, &PaddingBytesAfterNames,
+      &PaddingBytesAfterVTable, &PaddingBytesAfterVNames);
+
+  CurrentFileOffset = 0;
+  uint64_t FileOffsetToCounters = CurrentFileOffset +
+                                  sizeof(__llvm_profile_header) + DataSize +
+                                  PaddingBytesBeforeCounters;
+
   /* Map the profile. */
   char *Profile = (char *)mmap(NULL, FileSize, PROT_READ | PROT_WRITE,
-                               MAP_SHARED, fileno(File), 0);
+                               MAP_SHARED, Fileno, 0);
   if (Profile == MAP_FAILED) {
     PROF_ERR("Unable to mmap profile: %s\n", strerror(errno));
     return 1;
   }
-  const uint64_t CountersOffsetInBiasMode =
-      sizeof(__llvm_profile_header) + __llvm_write_binary_ids(NULL) + DataSize;
   /* Update the profile fields based on the current mapping. */
   INSTR_PROF_PROFILE_COUNTER_BIAS_VAR =
-      (intptr_t)Profile - (uintptr_t)CountersBegin + CountersOffsetInBiasMode;
+      (intptr_t)Profile - (uintptr_t)CountersBegin + FileOffsetToCounters;
 
   /* Return the memory allocated for counters to OS. */
   lprofReleaseMemoryPagesToOS((uintptr_t)CountersBegin, (uintptr_t)CountersEnd);

[ornata]

Why?

[chapuni]

Why?

"I want to introduce bitmap bias w/o posting RFC."

Rather than appending similar changes (but with different variables) into linux impl, I think it'd be better to align blocks with same variable for possible commonization in the future. It can also make simpler to explain the difference of bitmap between APPLE and bias mode.

To introduce bitmap in biased continuous mode, the bias for counters cannot be reused since the layout of __llvm_prf_bits and __llvm_prf_cnts is different from profraw.

I thought actual commonization would be too early since it would be intrusive.

[ornata]

LGTM

[ilovepi]

We're seeing test failures after this patch. Can you please take a look?

Bot: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-linux-arm64/b8744624520905017585/overview

Error:

FAIL: Profile-aarch64 :: ContinuousSyncMode/runtime-counter-relocation.c (2289 of 15086)
******************** TEST 'Profile-aarch64 :: ContinuousSyncMode/runtime-counter-relocation.c' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 3: /b/s/w/ir/x/w/llvm_build/./bin/clang    -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta   -ldl -fprofile-instr-generate -fcoverage-mapping -mllvm -runtime-counter-relocation=true -o /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.exe /b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c
+ /b/s/w/ir/x/w/llvm_build/./bin/clang -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta -ldl -fprofile-instr-generate -fcoverage-mapping -mllvm -runtime-counter-relocation=true -o /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.exe /b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c
RUN: at line 4: echo "garbage" > /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.profraw
+ echo garbage
RUN: at line 5: env LLVM_PROFILE_FILE="%c/b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.profraw"  /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.exe
+ env LLVM_PROFILE_FILE=%c/b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.profraw /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.exe
RUN: at line 6: llvm-profdata show --counts --all-functions /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.profraw | FileCheck /b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c -check-prefix=CHECK-COUNTS
+ llvm-profdata show --counts --all-functions /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-aarch64-unknown-linux-gnu-bins/compiler-rt/test/profile/Profile-aarch64/ContinuousSyncMode/Output/runtime-counter-relocation.c.tmp.profraw
+ FileCheck /b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c -check-prefix=CHECK-COUNTS
/b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c:14:23: error: CHECK-COUNTS-NEXT: expected string not found in input
// CHECK-COUNTS-NEXT: Function count: 1
                      ^
<stdin>:4:13: note: scanning from here
 Counters: 2
            ^
<stdin>:5:2: note: possible intended match here
 Function count: 0
 ^

Input file: <stdin>
Check file: /b/s/w/ir/x/w/llvm-llvm-project/compiler-rt/test/profile/ContinuousSyncMode/runtime-counter-relocation.c

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           1: Counters: 
           2:  main: 
           3:  Hash: 0x000000000a498458 
           4:  Counters: 2 
next:14'0                 X error: no match found
           5:  Function count: 0 
next:14'0     ~~~~~~~~~~~~~~~~~~~
next:14'1      ?                  possible intended match
           6:  Block counts: [0] 
next:14'0     ~~~~~~~~~~~~~~~~~~~
           7: Instrumentation level: Front-end 
next:14'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           8: Functions shown: 1 
next:14'0     ~~~~~~~~~~~~~~~~~~~
           9: Total functions: 1 
next:14'0     ~~~~~~~~~~~~~~~~~~~
          10: Maximum function count: 0 
next:14'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~
          11: Maximum internal block count: 0 
next:14'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>>>>

--

********************
PASS: Profile-aarch64 :: Linux/coverage_ctors.cpp (2290 of 15086)

[chapuni]

@ilovepi Thanks for reporting. I've reverted this and I'll rework with less-intrusive way.

[ilovepi]

Thanks.