From 6e9f06ee6c9566f3606d93182ac8f803a148504b Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 28 Jul 2020 18:54:40 +0200 Subject: Revert "parisc: Use ldcw instruction for SMP spinlock release barrier" 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 Cc: # v5.2+ --- arch/parisc/include/asm/spinlock.h | 4 ---- arch/parisc/kernel/entry.S | 43 ++++++++++++++++++-------------------- arch/parisc/kernel/syscall.S | 16 ++++---------- 3 files changed, 24 insertions(+), 39 deletions(-) (limited to 'arch') diff --git a/arch/parisc/include/asm/spinlock.h b/arch/parisc/include/asm/spinlock.h index d2a3337599fb..6f85ca70ce23 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 4b484ec7c7da..06455f1a40f5 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 ea505a81f821..472ce9921b30 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 -- cgit v1.2.3