diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/arm/include/asm/tls.h | 35 |
1 files changed, 25 insertions, 10 deletions
diff --git a/arch/arm/include/asm/tls.h b/arch/arm/include/asm/tls.h index 5a66c3b13c92..3dcd0f71a0da 100644 --- a/arch/arm/include/asm/tls.h +++ b/arch/arm/include/asm/tls.h @@ -12,44 +12,59 @@ .macro switch_tls_v6k, base, tp, tpuser, tmp1, tmp2 mrc p15, 0, \tmp2, c13, c0, 2 @ get the user r/w register - mcr p15, 0, \tp, c13, c0, 3 @ set TLS register - mcr p15, 0, \tpuser, c13, c0, 2 @ and the user r/w register + @ TLS register update is deferred until return to user space + mcr p15, 0, \tpuser, c13, c0, 2 @ set the user r/w register str \tmp2, [\base, #TI_TP_VALUE + 4] @ save it .endm .macro switch_tls_v6, base, tp, tpuser, tmp1, tmp2 - ldr \tmp1, =elf_hwcap - ldr \tmp1, [\tmp1, #0] +#ifdef CONFIG_SMP +ALT_SMP(nop) +ALT_UP_B(.L0_\@) + .subsection 1 +#endif +.L0_\@: + ldr_va \tmp1, elf_hwcap mov \tmp2, #0xffff0fff tst \tmp1, #HWCAP_TLS @ hardware TLS available? streq \tp, [\tmp2, #-15] @ set TLS value at 0xffff0ff0 - mrcne p15, 0, \tmp2, c13, c0, 2 @ get the user r/w register - mcrne p15, 0, \tp, c13, c0, 3 @ yes, set TLS register - mcrne p15, 0, \tpuser, c13, c0, 2 @ set user r/w register - strne \tmp2, [\base, #TI_TP_VALUE + 4] @ save it + beq .L2_\@ + mcr p15, 0, \tp, c13, c0, 3 @ yes, set TLS register +#ifdef CONFIG_SMP + b .L1_\@ + .previous +#endif +.L1_\@: switch_tls_v6k \base, \tp, \tpuser, \tmp1, \tmp2 +.L2_\@: .endm .macro switch_tls_software, base, tp, tpuser, tmp1, tmp2 mov \tmp1, #0xffff0fff str \tp, [\tmp1, #-15] @ set TLS value at 0xffff0ff0 .endm +#else +#include <asm/smp_plat.h> #endif #ifdef CONFIG_TLS_REG_EMUL #define tls_emu 1 #define has_tls_reg 1 +#define defer_tls_reg_update 0 #define switch_tls switch_tls_none #elif defined(CONFIG_CPU_V6) #define tls_emu 0 #define has_tls_reg (elf_hwcap & HWCAP_TLS) +#define defer_tls_reg_update is_smp() #define switch_tls switch_tls_v6 #elif defined(CONFIG_CPU_32v6K) #define tls_emu 0 #define has_tls_reg 1 +#define defer_tls_reg_update 1 #define switch_tls switch_tls_v6k #else #define tls_emu 0 #define has_tls_reg 0 +#define defer_tls_reg_update 0 #define switch_tls switch_tls_software #endif @@ -78,10 +93,10 @@ static inline void set_tls(unsigned long val) barrier(); if (!tls_emu) { - if (has_tls_reg) { + if (has_tls_reg && !defer_tls_reg_update) { asm("mcr p15, 0, %0, c13, c0, 3" : : "r" (val)); - } else { + } else if (!has_tls_reg) { #ifdef CONFIG_KUSER_HELPERS /* * User space must never try to access this |