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MdePkg/SynchronizationLib: fix Interlocked[De|In]crement return value

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REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1197

Today's InterlockedIncrement()/InterlockedDecrement() guarantees to
perform atomic increment/decrement but doesn't guarantee the return
value equals to the new value.

The patch fixes the behavior to use "XADD" instruction to guarantee
the return value equals to the new value.

The patch calls intrinsic functions for MSVC tool chain, calls the
NASM implementation for INTEL tool chain and calls GCC inline
assembly implementation (GccInline.c) for GCC tool chain.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
This commit is contained in:
Ruiyu Ni
2018-09-07 17:26:14 +08:00
parent ca3e4f8ab8
commit 17634d026f
16 changed files with 56 additions and 152 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c
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@@ -15,14 +15,12 @@
/**
Performs an atomic increment of an 32-bit unsigned integer.
Performs an atomic increment of the 32-bit unsigned integer specified by
Value and returns the incremented value. The increment operation must be
performed using MP safe mechanisms. The state of the return value is not
guaranteed to be MP safe.
performed using MP safe mechanisms.
@param Value A pointer to the 32-bit value to increment.
@@ -38,9 +36,10 @@ InternalSyncIncrement (
UINT32 Result;
__asm__ __volatile__ (
"movl $1, %%eax \n\t"
"lock \n\t"
"incl %2 \n\t"
"mov %2, %%eax "
"xadd %%eax, %2 \n\t"
"inc %%eax "
: "=a" (Result), // %0
"=m" (*Value) // %1
: "m" (*Value) // %2
@@ -57,8 +56,7 @@ InternalSyncIncrement (
Performs an atomic decrement of the 32-bit unsigned integer specified by
Value and returns the decremented value. The decrement operation must be
performed using MP safe mechanisms. The state of the return value is not
guaranteed to be MP safe.
performed using MP safe mechanisms.
@param Value A pointer to the 32-bit value to decrement.
@@ -74,9 +72,10 @@ InternalSyncDecrement (
UINT32 Result;
__asm__ __volatile__ (
"lock \n\t"
"decl %2 \n\t"
"mov %2, %%eax "
"movl $-1, %%eax \n\t"
"lock \n\t"
"xadd %%eax, %2 \n\t"
"dec %%eax "
: "=a" (Result), // %0
"=m" (*Value) // %1
: "m" (*Value) // %2