Re: cpu2000(both float and int) 13% regression with 2.6.28-rc1
From: Ingo Molnar
Date: Tue Oct 28 2008 - 04:04:10 EST
* Zhang, Yanmin <yanmin_zhang@xxxxxxxxxxxxxxx> wrote:
> Comparing with 2.6.27, cpu2000 (both float and int) has about 13% regression
> with 2.6.28-rc1 ïon my new-model x86-64 machine.
>
> I bisected down to below patch.
>
> commit 0afe2db21394820d32646a695eccf3fbfe6ab5c7
> Merge: d847059... 43603c8...
> Author: Ingo Molnar <mingo@xxxxxxx>
> Date: Sat Oct 11 20:23:20 2008 +0200
>
> Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-D
>
> Conflicts:
> arch/x86/kernel/cpu/common.c
> arch/x86/kernel/signal_64.c
> include/asm-x86/cpufeature.h
>
>
> When I tried to revert it against 2.6.28-rc2, there are many conflictions.
My guess right now is that it's the merge commit's doing, see the diff
below. Could you undo just the restore_sigcontext() chunk of it, in
arch/x86/kernel/signal_64.c:
@@@ -157,20 -96,9 +94,9 @@@ restore_sigcontext(struct pt_regs *regs
I've attached it as a patch below, apply it with "patch -p1 -R"
(I've also attached the full merge commit further below - just in case
it's in another portion of it.)
Ingo
---------------->
diff --cc arch/x86/kernel/signal_64.c
index 694aa88,4665b59..823a55b
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@@ -157,20 -96,9 +94,9 @@@ restore_sigcontext(struct pt_regs *regs
}
{
- struct _fpstate __user * buf;
+ struct _fpstate __user *buf;
err |= __get_user(buf, &sc->fpstate);
-
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387(buf);
- } else {
- struct task_struct *me = current;
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
+ err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
------------------->
commit 0afe2db21394820d32646a695eccf3fbfe6ab5c7
Merge: d847059... 43603c8...
Author: Ingo Molnar <mingo@xxxxxxx>
Date: Sat Oct 11 20:23:20 2008 +0200
Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-D
Conflicts:
arch/x86/kernel/cpu/common.c
arch/x86/kernel/signal_64.c
include/asm-x86/cpufeature.h
diff --cc arch/x86/kernel/sigframe.h
index 8b4956e,6dd7e2b..cc673aa
--- a/arch/x86/kernel/sigframe.h
+++ b/arch/x86/kernel/sigframe.h
@@@ -23,10 -32,6 +32,11 @@@ struct rt_sigframe
char __user *pretcode;
struct ucontext uc;
struct siginfo info;
+ /* fp state follows here */
};
+
+int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs);
+int ia32_setup_frame(int sig, struct k_sigaction *ka,
+ sigset_t *set, struct pt_regs *regs);
#endif
diff --cc arch/x86/kernel/signal_64.c
index 694aa88,4665b59..823a55b
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@@ -157,20 -96,9 +94,9 @@@ restore_sigcontext(struct pt_regs *regs
}
{
- struct _fpstate __user * buf;
+ struct _fpstate __user *buf;
err |= __get_user(buf, &sc->fpstate);
-
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387(buf);
- } else {
- struct task_struct *me = current;
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
+ err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
@@@ -273,10 -197,10 +196,10 @@@ get_stack(struct k_sigaction *ka, struc
}
static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs * regs)
+ sigset_t *set, struct pt_regs *regs)
{
struct rt_sigframe __user *frame;
- struct _fpstate __user *fp = NULL;
+ void __user *fp = NULL;
int err = 0;
struct task_struct *me = current;
@@@ -285,11 -209,8 +208,8 @@@
frame = (void __user *)round_down(
(unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
- if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
- goto give_sigsegv;
-
- if (save_i387(fp) < 0)
+ if (save_i387_xstate(fp) < 0)
- err |= -1;
+ err |= -1;
} else
frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
@@@ -301,9 -222,12 +221,12 @@@
if (err)
goto give_sigsegv;
}
-
+
/* Create the ucontext. */
- err |= __put_user(0, &frame->uc.uc_flags);
+ if (cpu_has_xsave)
+ err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
diff --cc include/asm-x86/cpufeature.h
index 065c6a8,8d45690..adfeae6
--- a/include/asm-x86/cpufeature.h
+++ b/include/asm-x86/cpufeature.h
@@@ -64,49 -72,61 +72,63 @@@
#define X86_FEATURE_CYRIX_ARR (3*32+ 2) /* Cyrix ARRs (= MTRRs) */
#define X86_FEATURE_CENTAUR_MCR (3*32+ 3) /* Centaur MCRs (= MTRRs) */
/* cpu types for specific tunings: */
- #define X86_FEATURE_K8 (3*32+ 4) /* Opteron, Athlon64 */
- #define X86_FEATURE_K7 (3*32+ 5) /* Athlon */
- #define X86_FEATURE_P3 (3*32+ 6) /* P3 */
- #define X86_FEATURE_P4 (3*32+ 7) /* P4 */
+ #define X86_FEATURE_K8 (3*32+ 4) /* "" Opteron, Athlon64 */
+ #define X86_FEATURE_K7 (3*32+ 5) /* "" Athlon */
+ #define X86_FEATURE_P3 (3*32+ 6) /* "" P3 */
+ #define X86_FEATURE_P4 (3*32+ 7) /* "" P4 */
#define X86_FEATURE_CONSTANT_TSC (3*32+ 8) /* TSC ticks at a constant rate */
#define X86_FEATURE_UP (3*32+ 9) /* smp kernel running on up */
- #define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* FXSAVE leaks FOP/FIP/FOP */
+ #define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* "" FXSAVE leaks FOP/FIP/FOP */
#define X86_FEATURE_ARCH_PERFMON (3*32+11) /* Intel Architectural PerfMon */
++#define X86_FEATURE_NOPL (3*32+20) /* The NOPL (0F 1F) instructions */
#define X86_FEATURE_PEBS (3*32+12) /* Precise-Event Based Sampling */
#define X86_FEATURE_BTS (3*32+13) /* Branch Trace Store */
- #define X86_FEATURE_SYSCALL32 (3*32+14) /* syscall in ia32 userspace */
- #define X86_FEATURE_SYSENTER32 (3*32+15) /* sysenter in ia32 userspace */
- #define X86_FEATURE_REP_GOOD (3*32+16) /* rep microcode works well on this CPU */
- #define X86_FEATURE_MFENCE_RDTSC (3*32+17) /* Mfence synchronizes RDTSC */
- #define X86_FEATURE_LFENCE_RDTSC (3*32+18) /* Lfence synchronizes RDTSC */
- #define X86_FEATURE_11AP (3*32+19) /* Bad local APIC aka 11AP */
+ #define X86_FEATURE_SYSCALL32 (3*32+14) /* "" syscall in ia32 userspace */
+ #define X86_FEATURE_SYSENTER32 (3*32+15) /* "" sysenter in ia32 userspace */
+ #define X86_FEATURE_REP_GOOD (3*32+16) /* rep microcode works well */
+ #define X86_FEATURE_MFENCE_RDTSC (3*32+17) /* "" Mfence synchronizes RDTSC */
+ #define X86_FEATURE_LFENCE_RDTSC (3*32+18) /* "" Lfence synchronizes RDTSC */
+ #define X86_FEATURE_11AP (3*32+19) /* "" Bad local APIC aka 11AP */
#define X86_FEATURE_NOPL (3*32+20) /* The NOPL (0F 1F) instructions */
+#define X86_FEATURE_AMDC1E (3*32+21) /* AMD C1E detected */
+ #define X86_FEATURE_XTOPOLOGY (3*32+21) /* cpu topology enum extensions */
/* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */
- #define X86_FEATURE_XMM3 (4*32+ 0) /* Streaming SIMD Extensions-3 */
- #define X86_FEATURE_MWAIT (4*32+ 3) /* Monitor/Mwait support */
- #define X86_FEATURE_DSCPL (4*32+ 4) /* CPL Qualified Debug Store */
+ #define X86_FEATURE_XMM3 (4*32+ 0) /* "pni" SSE-3 */
+ #define X86_FEATURE_PCLMULQDQ (4*32+ 1) /* PCLMULQDQ instruction */
+ #define X86_FEATURE_DTES64 (4*32+ 2) /* 64-bit Debug Store */
+ #define X86_FEATURE_MWAIT (4*32+ 3) /* "monitor" Monitor/Mwait support */
+ #define X86_FEATURE_DSCPL (4*32+ 4) /* "ds_cpl" CPL Qual. Debug Store */
+ #define X86_FEATURE_VMX (4*32+ 5) /* Hardware virtualization */
+ #define X86_FEATURE_SMX (4*32+ 6) /* Safer mode */
#define X86_FEATURE_EST (4*32+ 7) /* Enhanced SpeedStep */
#define X86_FEATURE_TM2 (4*32+ 8) /* Thermal Monitor 2 */
+ #define X86_FEATURE_SSSE3 (4*32+ 9) /* Supplemental SSE-3 */
#define X86_FEATURE_CID (4*32+10) /* Context ID */
+ #define X86_FEATURE_FMA (4*32+12) /* Fused multiply-add */
#define X86_FEATURE_CX16 (4*32+13) /* CMPXCHG16B */
#define X86_FEATURE_XTPR (4*32+14) /* Send Task Priority Messages */
+ #define X86_FEATURE_PDCM (4*32+15) /* Performance Capabilities */
#define X86_FEATURE_DCA (4*32+18) /* Direct Cache Access */
+ #define X86_FEATURE_XMM4_1 (4*32+19) /* "sse4_1" SSE-4.1 */
+ #define X86_FEATURE_XMM4_2 (4*32+20) /* "sse4_2" SSE-4.2 */
#define X86_FEATURE_X2APIC (4*32+21) /* x2APIC */
- #define X86_FEATURE_XMM4_2 (4*32+20) /* Streaming SIMD Extensions-4.2 */
+ #define X86_FEATURE_AES (4*32+25) /* AES instructions */
+ #define X86_FEATURE_XSAVE (4*32+26) /* XSAVE/XRSTOR/XSETBV/XGETBV */
+ #define X86_FEATURE_OSXSAVE (4*32+27) /* "" XSAVE enabled in the OS */
+ #define X86_FEATURE_AVX (4*32+28) /* Advanced Vector Extensions */
/* VIA/Cyrix/Centaur-defined CPU features, CPUID level 0xC0000001, word 5 */
- #define X86_FEATURE_XSTORE (5*32+ 2) /* on-CPU RNG present (xstore insn) */
- #define X86_FEATURE_XSTORE_EN (5*32+ 3) /* on-CPU RNG enabled */
- #define X86_FEATURE_XCRYPT (5*32+ 6) /* on-CPU crypto (xcrypt insn) */
- #define X86_FEATURE_XCRYPT_EN (5*32+ 7) /* on-CPU crypto enabled */
+ #define X86_FEATURE_XSTORE (5*32+ 2) /* "rng" RNG present (xstore) */
+ #define X86_FEATURE_XSTORE_EN (5*32+ 3) /* "rng_en" RNG enabled */
+ #define X86_FEATURE_XCRYPT (5*32+ 6) /* "ace" on-CPU crypto (xcrypt) */
+ #define X86_FEATURE_XCRYPT_EN (5*32+ 7) /* "ace_en" on-CPU crypto enabled */
#define X86_FEATURE_ACE2 (5*32+ 8) /* Advanced Cryptography Engine v2 */
#define X86_FEATURE_ACE2_EN (5*32+ 9) /* ACE v2 enabled */
- #define X86_FEATURE_PHE (5*32+ 10) /* PadLock Hash Engine */
- #define X86_FEATURE_PHE_EN (5*32+ 11) /* PHE enabled */
- #define X86_FEATURE_PMM (5*32+ 12) /* PadLock Montgomery Multiplier */
- #define X86_FEATURE_PMM_EN (5*32+ 13) /* PMM enabled */
+ #define X86_FEATURE_PHE (5*32+10) /* PadLock Hash Engine */
+ #define X86_FEATURE_PHE_EN (5*32+11) /* PHE enabled */
+ #define X86_FEATURE_PMM (5*32+12) /* PadLock Montgomery Multiplier */
+ #define X86_FEATURE_PMM_EN (5*32+13) /* PMM enabled */
/* More extended AMD flags: CPUID level 0x80000001, ecx, word 6 */
#define X86_FEATURE_LAHF_LM (6*32+ 0) /* LAHF/SAHF in long mode */
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