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authorMarcelo Tosatti <mtosatti@redhat.com>2013-03-05 00:10:32 +0100
committerMarcelo Tosatti <mtosatti@redhat.com>2013-03-05 00:10:32 +0100
commitee2c25efdd46d7ed5605d6fe877bdf4b47a4ab2e (patch)
tree35890281e93e667a8e262d76ef250025eb30a8c1 /arch/mips/math-emu/cp1emu.c
parentKVM: VMX: Pass vcpu to __vmx_complete_interrupts (diff)
parentLinux 3.9-rc1 (diff)
downloadlinux-ee2c25efdd46d7ed5605d6fe877bdf4b47a4ab2e.tar.xz
linux-ee2c25efdd46d7ed5605d6fe877bdf4b47a4ab2e.zip
Merge branch 'master' into queue
* master: (15791 commits) Linux 3.9-rc1 btrfs/raid56: Add missing #include <linux/vmalloc.h> fix compat_sys_rt_sigprocmask() SUNRPC: One line comment fix ext4: enable quotas before orphan cleanup ext4: don't allow quota mount options when quota feature enabled ext4: fix a warning from sparse check for ext4_dir_llseek ext4: convert number of blocks to clusters properly ext4: fix possible memory leak in ext4_remount() jbd2: fix ERR_PTR dereference in jbd2__journal_start metag: Provide dma_get_sgtable() metag: prom.h: remove declaration of metag_dt_memblock_reserve() metag: copy devicetree to non-init memory metag: cleanup metag_ksyms.c includes metag: move mm/init.c exports out of metag_ksyms.c metag: move usercopy.c exports out of metag_ksyms.c metag: move setup.c exports out of metag_ksyms.c metag: move kick.c exports out of metag_ksyms.c metag: move traps.c exports out of metag_ksyms.c metag: move irq enable out of irqflags.h on SMP ... Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Conflicts: arch/x86/kernel/kvmclock.c
Diffstat (limited to 'arch/mips/math-emu/cp1emu.c')
-rw-r--r--arch/mips/math-emu/cp1emu.c23
1 files changed, 12 insertions, 11 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index a03bf00a1a9c..afb5a0bcf7a5 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -169,18 +169,19 @@ static int isBranchInstr(mips_instruction * i)
/*
* In the Linux kernel, we support selection of FPR format on the
- * basis of the Status.FR bit. If an FPU is not present, the FR bit
+ * basis of the Status.FR bit. If an FPU is not present, the FR bit
* is hardwired to zero, which would imply a 32-bit FPU even for
- * 64-bit CPUs. For 64-bit kernels with no FPU we use TIF_32BIT_REGS
- * as a proxy for the FR bit so that a 64-bit FPU is emulated. In any
- * case, for a 32-bit kernel which uses the O32 MIPS ABI, only the
- * even FPRs are used (Status.FR = 0).
+ * 64-bit CPUs so we rather look at TIF_32BIT_REGS.
+ * FPU emu is slow and bulky and optimizing this function offers fairly
+ * sizeable benefits so we try to be clever and make this function return
+ * a constant whenever possible, that is on 64-bit kernels without O32
+ * compatibility enabled and on 32-bit kernels.
*/
static inline int cop1_64bit(struct pt_regs *xcp)
{
- if (cpu_has_fpu)
- return xcp->cp0_status & ST0_FR;
-#ifdef CONFIG_64BIT
+#if defined(CONFIG_64BIT) && !defined(CONFIG_MIPS32_O32)
+ return 1;
+#elif defined(CONFIG_64BIT) && defined(CONFIG_MIPS32_O32)
return !test_thread_flag(TIF_32BIT_REGS);
#else
return 0;
@@ -233,7 +234,7 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
if (xcp->cp0_cause & CAUSEF_BD) {
/*
* The instruction to be emulated is in a branch delay slot
- * which means that we have to emulate the branch instruction
+ * which means that we have to emulate the branch instruction
* BEFORE we do the cop1 instruction.
*
* This branch could be a COP1 branch, but in that case we
@@ -1334,8 +1335,8 @@ int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
else {
/*
* The 'ieee754_csr' is an alias of
- * ctx->fcr31. No need to copy ctx->fcr31 to
- * ieee754_csr. But ieee754_csr.rm is ieee
+ * ctx->fcr31. No need to copy ctx->fcr31 to
+ * ieee754_csr. But ieee754_csr.rm is ieee
* library modes. (not mips rounding mode)
*/
/* convert to ieee library modes */