Short range flushes issue a sequences of tlbie(l) instructions for
individual effective addresses. These do not all require individual
barrier sequences, only one covering all tlbie(l) instructions.
Commit f7327e0ba3 ("powerpc/mm/radix: Remove unnecessary ptesync")
made a similar optimization for tlbiel for PID flushing.
For tlbie, the ISA says:
The tlbsync instruction provides an ordering function for the
effects of all tlbie instructions executed by the thread executing
the tlbsync instruction, with respect to the memory barrier
created by a subsequent ptesync instruction executed by the same
thread.
Time to munmap 30 pages of memory (after mmap, touch):
local global
vanilla 10.9us 22.3us
patched 3.4us 14.4us
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/mm/tlb-radix.c | 41 ++++++++++++++++++++++++++++++++---------
1 file changed, 32 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c
index 6e77ed2d7c6c..49e71c68f5b1 100644
--- a/arch/powerpc/mm/tlb-radix.c
+++ b/arch/powerpc/mm/tlb-radix.c
@@ -84,7 +84,7 @@ static inline void _tlbie_pid(unsigned long pid, unsigned
long ric)
trace_tlbie(0, 0, rb, rs, ric, prs, r);
}
-static inline void _tlbiel_va(unsigned long va, unsigned long pid,
+static inline void __tlbiel_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
@@ -95,14 +95,20 @@ static inline void _tlbiel_va(unsigned long va, unsigned
long pid,
prs = 1; /* process scoped */
r = 1; /* raidx format */
- asm volatile("ptesync": : :"memory");
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) :
"memory");
- asm volatile("ptesync": : :"memory");
trace_tlbie(0, 1, rb, rs, ric, prs, r);
}
-static inline void _tlbie_va(unsigned long va, unsigned long pid,
+static inline void _tlbiel_va(unsigned long va, unsigned long pid,
+ unsigned long ap, unsigned long ric)
+{
+ asm volatile("ptesync": : :"memory");
+ __tlbiel_va(va, pid, ap, ric);
+ asm volatile("ptesync": : :"memory");
+}
+
+static inline void __tlbie_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
@@ -113,13 +119,20 @@ static inline void _tlbie_va(unsigned long va, unsigned
long pid,
prs = 1; /* process scoped */
r = 1; /* raidx format */
- asm volatile("ptesync": : :"memory");
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) :
"memory");
- asm volatile("eieio; tlbsync; ptesync": : :"memory");
trace_tlbie(0, 0, rb, rs, ric, prs, r);
}
+static inline void _tlbie_va(unsigned long va, unsigned long pid,
+ unsigned long ap, unsigned long ric)
+{
+ asm volatile("ptesync": : :"memory");
+ __tlbie_va(va, pid, ap, ric);
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+
/*
* Base TLB flushing operations:
*
@@ -341,13 +354,19 @@ void radix__flush_tlb_range_psize(struct mm_struct *mm,
unsigned long start,
_tlbiel_pid(pid, RIC_FLUSH_TLB);
else
_tlbie_pid(pid, RIC_FLUSH_TLB);
+
} else {
+ asm volatile("ptesync": : :"memory");
for (addr = start; addr < end; addr += page_size) {
if (local)
- _tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB);
+ __tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB);
else
- _tlbie_va(addr, pid, ap, RIC_FLUSH_TLB);
+ __tlbie_va(addr, pid, ap, RIC_FLUSH_TLB);
}
+ if (local)
+ asm volatile("ptesync": : :"memory");
+ else
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
preempt_enable();
@@ -380,6 +399,7 @@ void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm,
unsigned long addr)
_tlbie_pid(pid, RIC_FLUSH_PWC);
/* Then iterate the pages */
+ asm volatile("ptesync": : :"memory");
end = addr + HPAGE_PMD_SIZE;
for (; addr < end; addr += PAGE_SIZE) {
if (local)
@@ -387,7 +407,10 @@ void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm,
unsigned long addr)
else
_tlbie_va(addr, pid, ap, RIC_FLUSH_TLB);
}
-
+ if (local)
+ asm volatile("ptesync": : :"memory");
+ else
+ asm volatile("eieio; tlbsync; ptesync": : :"memory");
preempt_enable();
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
--
2.15.0
