From: Helge Deller Date: Tue, 28 Jul 2020 16:54:40 +0000 (+0200) Subject: Revert "parisc: Use ldcw instruction for SMP spinlock release barrier" X-Git-Tag: v5.15~3216^2~3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6e9f06ee6c9566f3606d93182ac8f803a148504b;p=platform%2Fkernel%2Flinux-starfive.git 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+ --- diff --git a/arch/parisc/include/asm/spinlock.h b/arch/parisc/include/asm/spinlock.h index d2a3337..6f85ca7 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 4b484ec..06455f1 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 ea505a8..472ce99 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