diff options
| author | Mikulas Patocka <mpatocka@redhat.com> | 2019-04-28 00:09:53 +0200 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2019-05-03 23:47:41 +0200 |
| commit | b37d1c1898b288c69f3dc9267bc2c41af06f4a4b (patch) | |
| tree | d041b4796035a447687ae8b1bc7d904c39f8729b /arch/parisc/kernel/entry.S | |
| parent | d19a12906e5e558c0f6b6cfece7b7caf1012ef95 (diff) | |
parisc: Use per-pagetable spinlock
PA-RISC uses a global spinlock to protect pagetable updates in the TLB
fault handlers. When multiple cores are taking TLB faults simultaneously,
the cache line containing the spinlock becomes a bottleneck.
This patch embeds the spinlock in the top level page directory, so that
every process has its own lock. It improves performance by 30% when
doing parallel compilations.
At least on the N class systems, only one PxTLB inter processor
broadcast can be active at any one time on the Merced bus. If a Merced
bus is found, this patch serializes the TLB flushes with the
pa_tlb_flush_lock spinlock.
v1: Initial patch by Mikulas
v2: Added Merced detection by Helge
v3: Revised TLB serialization by Dave & Helge
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc/kernel/entry.S')
| -rw-r--r-- | arch/parisc/kernel/entry.S | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index 5796524a3137..a1fc04570ade 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -50,12 +50,8 @@ .import pa_tlb_lock,data .macro load_pa_tlb_lock reg -#if __PA_LDCW_ALIGNMENT > 4 - load32 PA(pa_tlb_lock) + __PA_LDCW_ALIGNMENT-1, \reg - depi 0,31,__PA_LDCW_ALIGN_ORDER, \reg -#else - load32 PA(pa_tlb_lock), \reg -#endif + mfctl %cr25,\reg + addil L%(PAGE_SIZE << (PGD_ALLOC_ORDER - 1)),\reg .endm /* space_to_prot macro creates a prot id from a space id */ |