[PATCH v2 16/17] x86/insn: remove pcommit
From: Dan Williams
Date: Sat Jul 09 2016 - 23:28:50 EST
The pcommit instruction is being deprecated in favor of either ADR
(asynchronous DRAM refresh: flush-on-power-fail) at the platform level, or
posted-write-queue flush addresses as defined by the ACPI 6.x NFIT (NVDIMM
Firmware Interface Table).
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
arch/x86/include/asm/cpufeatures.h | 1
arch/x86/include/asm/special_insns.h | 46 --------------------
arch/x86/lib/x86-opcode-map.txt | 2 -
tools/objtool/arch/x86/insn/x86-opcode-map.txt | 2 -
tools/perf/arch/x86/tests/insn-x86-dat-32.c | 2 -
tools/perf/arch/x86/tests/insn-x86-dat-64.c | 2 -
tools/perf/arch/x86/tests/insn-x86-dat-src.c | 4 --
.../perf/util/intel-pt-decoder/x86-opcode-map.txt | 2 -
8 files changed, 3 insertions(+), 58 deletions(-)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 4a413485f9eb..700d97df7d28 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -225,7 +225,6 @@
#define X86_FEATURE_RDSEED ( 9*32+18) /* The RDSEED instruction */
#define X86_FEATURE_ADX ( 9*32+19) /* The ADCX and ADOX instructions */
#define X86_FEATURE_SMAP ( 9*32+20) /* Supervisor Mode Access Prevention */
-#define X86_FEATURE_PCOMMIT ( 9*32+22) /* PCOMMIT instruction */
#define X86_FEATURE_CLFLUSHOPT ( 9*32+23) /* CLFLUSHOPT instruction */
#define X86_FEATURE_CLWB ( 9*32+24) /* CLWB instruction */
#define X86_FEATURE_AVX512PF ( 9*32+26) /* AVX-512 Prefetch */
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index d96d04377765..587d7914ea4b 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -253,52 +253,6 @@ static inline void clwb(volatile void *__p)
: [pax] "a" (p));
}
-/**
- * pcommit_sfence() - persistent commit and fence
- *
- * The PCOMMIT instruction ensures that data that has been flushed from the
- * processor's cache hierarchy with CLWB, CLFLUSHOPT or CLFLUSH is accepted to
- * memory and is durable on the DIMM. The primary use case for this is
- * persistent memory.
- *
- * This function shows how to properly use CLWB/CLFLUSHOPT/CLFLUSH and PCOMMIT
- * with appropriate fencing.
- *
- * Example:
- * void flush_and_commit_buffer(void *vaddr, unsigned int size)
- * {
- * unsigned long clflush_mask = boot_cpu_data.x86_clflush_size - 1;
- * void *vend = vaddr + size;
- * void *p;
- *
- * for (p = (void *)((unsigned long)vaddr & ~clflush_mask);
- * p < vend; p += boot_cpu_data.x86_clflush_size)
- * clwb(p);
- *
- * // SFENCE to order CLWB/CLFLUSHOPT/CLFLUSH cache flushes
- * // MFENCE via mb() also works
- * wmb();
- *
- * // PCOMMIT and the required SFENCE for ordering
- * pcommit_sfence();
- * }
- *
- * After this function completes the data pointed to by 'vaddr' has been
- * accepted to memory and will be durable if the 'vaddr' points to persistent
- * memory.
- *
- * PCOMMIT must always be ordered by an MFENCE or SFENCE, so to help simplify
- * things we include both the PCOMMIT and the required SFENCE in the
- * alternatives generated by pcommit_sfence().
- */
-static inline void pcommit_sfence(void)
-{
- alternative(ASM_NOP7,
- ".byte 0x66, 0x0f, 0xae, 0xf8\n\t" /* pcommit */
- "sfence",
- X86_FEATURE_PCOMMIT);
-}
-
#define nop() asm volatile ("nop")
diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt
index d388de72eaca..28632ee68377 100644
--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -947,7 +947,7 @@ GrpTable: Grp15
4: XSAVE
5: XRSTOR | lfence (11B)
6: XSAVEOPT | clwb (66) | mfence (11B)
-7: clflush | clflushopt (66) | sfence (11B) | pcommit (66),(11B)
+7: clflush | clflushopt (66) | sfence (11B)
EndTable
GrpTable: Grp16
diff --git a/tools/objtool/arch/x86/insn/x86-opcode-map.txt b/tools/objtool/arch/x86/insn/x86-opcode-map.txt
index d388de72eaca..28632ee68377 100644
--- a/tools/objtool/arch/x86/insn/x86-opcode-map.txt
+++ b/tools/objtool/arch/x86/insn/x86-opcode-map.txt
@@ -947,7 +947,7 @@ GrpTable: Grp15
4: XSAVE
5: XRSTOR | lfence (11B)
6: XSAVEOPT | clwb (66) | mfence (11B)
-7: clflush | clflushopt (66) | sfence (11B) | pcommit (66),(11B)
+7: clflush | clflushopt (66) | sfence (11B)
EndTable
GrpTable: Grp16
diff --git a/tools/perf/arch/x86/tests/insn-x86-dat-32.c b/tools/perf/arch/x86/tests/insn-x86-dat-32.c
index 3b491cfe204e..38a48daed154 100644
--- a/tools/perf/arch/x86/tests/insn-x86-dat-32.c
+++ b/tools/perf/arch/x86/tests/insn-x86-dat-32.c
@@ -654,5 +654,3 @@
"0f c7 1d 78 56 34 12 \txrstors 0x12345678",},
{{0x0f, 0xc7, 0x9c, 0xc8, 0x78, 0x56, 0x34, 0x12, }, 8, 0, "", "",
"0f c7 9c c8 78 56 34 12 \txrstors 0x12345678(%eax,%ecx,8)",},
-{{0x66, 0x0f, 0xae, 0xf8, }, 4, 0, "", "",
-"66 0f ae f8 \tpcommit ",},
diff --git a/tools/perf/arch/x86/tests/insn-x86-dat-64.c b/tools/perf/arch/x86/tests/insn-x86-dat-64.c
index 4fe7cce179c4..1f11ea85b60f 100644
--- a/tools/perf/arch/x86/tests/insn-x86-dat-64.c
+++ b/tools/perf/arch/x86/tests/insn-x86-dat-64.c
@@ -764,5 +764,3 @@
"0f c7 9c c8 78 56 34 12 \txrstors 0x12345678(%rax,%rcx,8)",},
{{0x41, 0x0f, 0xc7, 0x9c, 0xc8, 0x78, 0x56, 0x34, 0x12, }, 9, 0, "", "",
"41 0f c7 9c c8 78 56 34 12 \txrstors 0x12345678(%r8,%rcx,8)",},
-{{0x66, 0x0f, 0xae, 0xf8, }, 4, 0, "", "",
-"66 0f ae f8 \tpcommit ",},
diff --git a/tools/perf/arch/x86/tests/insn-x86-dat-src.c b/tools/perf/arch/x86/tests/insn-x86-dat-src.c
index 41b1b1c62660..033b8a6fdab9 100644
--- a/tools/perf/arch/x86/tests/insn-x86-dat-src.c
+++ b/tools/perf/arch/x86/tests/insn-x86-dat-src.c
@@ -866,10 +866,6 @@ int main(void)
#endif /* #ifndef __x86_64__ */
- /* pcommit */
-
- asm volatile("pcommit");
-
/* Following line is a marker for the awk script - do not change */
asm volatile("rdtsc"); /* Stop here */
diff --git a/tools/perf/util/intel-pt-decoder/x86-opcode-map.txt b/tools/perf/util/intel-pt-decoder/x86-opcode-map.txt
index d388de72eaca..28632ee68377 100644
--- a/tools/perf/util/intel-pt-decoder/x86-opcode-map.txt
+++ b/tools/perf/util/intel-pt-decoder/x86-opcode-map.txt
@@ -947,7 +947,7 @@ GrpTable: Grp15
4: XSAVE
5: XRSTOR | lfence (11B)
6: XSAVEOPT | clwb (66) | mfence (11B)
-7: clflush | clflushopt (66) | sfence (11B) | pcommit (66),(11B)
+7: clflush | clflushopt (66) | sfence (11B)
EndTable
GrpTable: Grp16