diff options
| author | Helge Deller <deller@gmx.de> | 2020-07-28 18:54:40 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-19 08:16:26 +0200 |
| commit | 431d999bd098144265fd399f16c888d01a12bc73 (patch) | |
| tree | 6267c41eb16695baeac0b894c5d622f4b6b7031b /arch/parisc | |
| parent | 7612ce180e30fa7f60731f12bf5d9d1664be60de (diff) | |
Revert "parisc: Use ldcw instruction for SMP spinlock release barrier"
commit 6e9f06ee6c9566f3606d93182ac8f803a148504b upstream.
This reverts commit 9e5c602186a692a7e848c0da17aed40f49d30519.
No need to use the ldcw instruction as SMP spinlock release barrier.
Revert it to gain back speed again.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/parisc')
| -rw-r--r-- | arch/parisc/include/asm/spinlock.h | 4 | ||||
| -rw-r--r-- | arch/parisc/kernel/entry.S | 43 | ||||
| -rw-r--r-- | arch/parisc/kernel/syscall.S | 16 |
3 files changed, 24 insertions, 39 deletions
diff --git a/arch/parisc/include/asm/spinlock.h b/arch/parisc/include/asm/spinlock.h index 197d2247e4db..8a63515f03bf 100644 --- a/arch/parisc/include/asm/spinlock.h +++ b/arch/parisc/include/asm/spinlock.h @@ -37,11 +37,7 @@ static inline void arch_spin_unlock(arch_spinlock_t *x) volatile unsigned int *a; a = __ldcw_align(x); -#ifdef CONFIG_SMP - (void) __ldcw(a); -#else mb(); -#endif *a = 1; } diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index b96d74496977..5d48efcb2683 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -454,9 +454,8 @@ nop LDREG 0(\ptp),\pte bb,<,n \pte,_PAGE_PRESENT_BIT,3f - LDCW 0(\tmp),\tmp1 b \fault - stw \spc,0(\tmp) + stw,ma \spc,0(\tmp) 99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP) #endif 2: LDREG 0(\ptp),\pte @@ -465,22 +464,20 @@ .endm /* Release pa_tlb_lock lock without reloading lock address. */ - .macro tlb_unlock0 spc,tmp,tmp1 + .macro tlb_unlock0 spc,tmp #ifdef CONFIG_SMP 98: or,COND(=) %r0,\spc,%r0 - LDCW 0(\tmp),\tmp1 - or,COND(=) %r0,\spc,%r0 - stw \spc,0(\tmp) + stw,ma \spc,0(\tmp) 99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP) #endif .endm /* Release pa_tlb_lock lock. */ - .macro tlb_unlock1 spc,tmp,tmp1 + .macro tlb_unlock1 spc,tmp #ifdef CONFIG_SMP 98: load_pa_tlb_lock \tmp 99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP) - tlb_unlock0 \spc,\tmp,\tmp1 + tlb_unlock0 \spc,\tmp #endif .endm @@ -1163,7 +1160,7 @@ dtlb_miss_20w: idtlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1189,7 +1186,7 @@ nadtlb_miss_20w: idtlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1223,7 +1220,7 @@ dtlb_miss_11: mtsp t1, %sr1 /* Restore sr1 */ - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1256,7 +1253,7 @@ nadtlb_miss_11: mtsp t1, %sr1 /* Restore sr1 */ - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1285,7 +1282,7 @@ dtlb_miss_20: idtlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1313,7 +1310,7 @@ nadtlb_miss_20: idtlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1420,7 +1417,7 @@ itlb_miss_20w: iitlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1444,7 +1441,7 @@ naitlb_miss_20w: iitlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1478,7 +1475,7 @@ itlb_miss_11: mtsp t1, %sr1 /* Restore sr1 */ - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1502,7 +1499,7 @@ naitlb_miss_11: mtsp t1, %sr1 /* Restore sr1 */ - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1532,7 +1529,7 @@ itlb_miss_20: iitlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1552,7 +1549,7 @@ naitlb_miss_20: iitlbt pte,prot - tlb_unlock1 spc,t0,t1 + tlb_unlock1 spc,t0 rfir nop @@ -1582,7 +1579,7 @@ dbit_trap_20w: idtlbt pte,prot - tlb_unlock0 spc,t0,t1 + tlb_unlock0 spc,t0 rfir nop #else @@ -1608,7 +1605,7 @@ dbit_trap_11: mtsp t1, %sr1 /* Restore sr1 */ - tlb_unlock0 spc,t0,t1 + tlb_unlock0 spc,t0 rfir nop @@ -1628,7 +1625,7 @@ dbit_trap_20: idtlbt pte,prot - tlb_unlock0 spc,t0,t1 + tlb_unlock0 spc,t0 rfir nop #endif diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index e54d5e4d3489..93cc36d98875 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -640,9 +640,7 @@ cas_action: sub,<> %r28, %r25, %r0 2: stw %r24, 0(%r26) /* Free lock */ -#ifdef CONFIG_SMP - LDCW 0(%sr2,%r20), %r1 /* Barrier */ -#endif + sync stw %r20, 0(%sr2,%r20) #if ENABLE_LWS_DEBUG /* Clear thread register indicator */ @@ -657,9 +655,7 @@ cas_action: 3: /* Error occurred on load or store */ /* Free lock */ -#ifdef CONFIG_SMP - LDCW 0(%sr2,%r20), %r1 /* Barrier */ -#endif + sync stw %r20, 0(%sr2,%r20) #if ENABLE_LWS_DEBUG stw %r0, 4(%sr2,%r20) @@ -861,9 +857,7 @@ cas2_action: cas2_end: /* Free lock */ -#ifdef CONFIG_SMP - LDCW 0(%sr2,%r20), %r1 /* Barrier */ -#endif + sync stw %r20, 0(%sr2,%r20) /* Enable interrupts */ ssm PSW_SM_I, %r0 @@ -874,9 +868,7 @@ cas2_end: 22: /* Error occurred on load or store */ /* Free lock */ -#ifdef CONFIG_SMP - LDCW 0(%sr2,%r20), %r1 /* Barrier */ -#endif + sync stw %r20, 0(%sr2,%r20) ssm PSW_SM_I, %r0 ldo 1(%r0),%r28 |