[scudo] Tuning changes based on feedback from current use
Summary:
This tunes several of the default parameters used within the allocator:
- disable the deallocation type mismatch on Android by default; this
was causing too many issues with third party libraries;
- change the default `SizeClassMap` to `Dense`, it caches less entries
and is way more memory efficient overall;
- relax the timing of the RSS checks, 10 times per second was too much,
lower it to 4 times (every 250ms), and update the test so that it
passes with the new default.
Reviewers: eugenis
Reviewed By: eugenis
Subscribers: srhines, delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D57116
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@352057 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/scudo/scudo_allocator.cpp b/lib/scudo/scudo_allocator.cpp
index fb04fb2..ca2441c 100644
--- a/lib/scudo/scudo_allocator.cpp
+++ b/lib/scudo/scudo_allocator.cpp
@@ -588,11 +588,11 @@
}
// Opportunistic RSS limit check. This will update the RSS limit status, if
-// it can, every 100ms, otherwise it will just return the current one.
+// it can, every 250ms, otherwise it will just return the current one.
NOINLINE bool Allocator::isRssLimitExceeded() {
u64 LastCheck = atomic_load_relaxed(&RssLastCheckedAtNS);
const u64 CurrentCheck = MonotonicNanoTime();
- if (LIKELY(CurrentCheck < LastCheck + (100ULL * 1000000ULL)))
+ if (LIKELY(CurrentCheck < LastCheck + (250ULL * 1000000ULL)))
return atomic_load_relaxed(&RssLimitExceeded);
if (!atomic_compare_exchange_weak(&RssLastCheckedAtNS, &LastCheck,
CurrentCheck, memory_order_relaxed))
diff --git a/lib/scudo/scudo_flags.inc b/lib/scudo/scudo_flags.inc
index f180478..0a4a7f1 100644
--- a/lib/scudo/scudo_flags.inc
+++ b/lib/scudo/scudo_flags.inc
@@ -37,7 +37,9 @@
"Size in bytes up to which chunks will be quarantined (if lower than"
"or equal to). Defaults to 256 (32-bit) or 2048 (64-bit)")
-SCUDO_FLAG(bool, DeallocationTypeMismatch, true,
+// Disable the deallocation type check by default on Android, it causes too many
+// issues with third party libraries.
+SCUDO_FLAG(bool, DeallocationTypeMismatch, !SANITIZER_ANDROID,
"Report errors on malloc/delete, new/free, new/delete[], etc.")
SCUDO_FLAG(bool, DeleteSizeMismatch, true,
diff --git a/lib/scudo/scudo_platform.h b/lib/scudo/scudo_platform.h
index 3a6f4be..fdae00b 100644
--- a/lib/scudo/scudo_platform.h
+++ b/lib/scudo/scudo_platform.h
@@ -80,7 +80,7 @@
#endif // SANITIZER_CAN_USE_ALLOCATOR64
#if !defined(SCUDO_SIZE_CLASS_MAP)
-# define SCUDO_SIZE_CLASS_MAP Default
+# define SCUDO_SIZE_CLASS_MAP Dense
#endif
#define SIZE_CLASS_MAP_TYPE SIZE_CLASS_MAP_TYPE_(SCUDO_SIZE_CLASS_MAP)
diff --git a/test/scudo/rss.c b/test/scudo/rss.c
index 4376290..f98bf95 100644
--- a/test/scudo/rss.c
+++ b/test/scudo/rss.c
@@ -1,15 +1,15 @@
// RUN: %clang_scudo %s -o %t
// RUN: %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-nolimit
-// RUN: %env_scudo_opts="soft_rss_limit_mb=256" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-nolimit
-// RUN: %env_scudo_opts="hard_rss_limit_mb=256" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-nolimit
-// RUN: %env_scudo_opts="soft_rss_limit_mb=64:allocator_may_return_null=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit
-// RUN: %env_scudo_opts="soft_rss_limit_mb=64:allocator_may_return_null=1" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit-returnnull
-// RUN: %env_scudo_opts="soft_rss_limit_mb=64:allocator_may_return_null=0:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit
-// RUN: %env_scudo_opts="soft_rss_limit_mb=64:allocator_may_return_null=1:can_use_proc_maps_statm=0" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit-returnnull
-// RUN: %env_scudo_opts="hard_rss_limit_mb=64:allocator_may_return_null=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
-// RUN: %env_scudo_opts="hard_rss_limit_mb=64:allocator_may_return_null=1" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
-// RUN: %env_scudo_opts="hard_rss_limit_mb=64:allocator_may_return_null=0:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
-// RUN: %env_scudo_opts="hard_rss_limit_mb=64:allocator_may_return_null=1:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
+// RUN: %env_scudo_opts="soft_rss_limit_mb=128" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-nolimit
+// RUN: %env_scudo_opts="hard_rss_limit_mb=128" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-nolimit
+// RUN: %env_scudo_opts="soft_rss_limit_mb=32:allocator_may_return_null=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit
+// RUN: %env_scudo_opts="soft_rss_limit_mb=32:allocator_may_return_null=1" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit-returnnull
+// RUN: %env_scudo_opts="soft_rss_limit_mb=32:allocator_may_return_null=0:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit
+// RUN: %env_scudo_opts="soft_rss_limit_mb=32:allocator_may_return_null=1:can_use_proc_maps_statm=0" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-softlimit-returnnull
+// RUN: %env_scudo_opts="hard_rss_limit_mb=32:allocator_may_return_null=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
+// RUN: %env_scudo_opts="hard_rss_limit_mb=32:allocator_may_return_null=1" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
+// RUN: %env_scudo_opts="hard_rss_limit_mb=32:allocator_may_return_null=0:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
+// RUN: %env_scudo_opts="hard_rss_limit_mb=32:allocator_may_return_null=1:can_use_proc_maps_statm=0" not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-hardlimit
// Tests that the soft and hard RSS limits work as intended. Without limit or
// with a high limit, the test should pass without any malloc returning NULL or
@@ -22,7 +22,7 @@
#include <string.h>
#include <unistd.h>
-static const size_t kNumAllocs = 128;
+static const size_t kNumAllocs = 64;
static const size_t kAllocSize = 1 << 20; // 1MB.
static void *allocs[kNumAllocs];
@@ -31,7 +31,7 @@
int returned_null = 0;
for (int i = 0; i < kNumAllocs; i++) {
if ((i & 0xf) == 0)
- usleep(50000);
+ usleep(100000);
allocs[i] = malloc(kAllocSize);
if (allocs[i])
memset(allocs[i], 0xff, kAllocSize); // Dirty the pages.
