diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2018-01-12 13:37:12 +1100 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2018-01-19 12:10:21 +1100 |
| commit | bf4159da4751ab8eea43ca6e7c49193dbce8398c (patch) | |
| tree | f388b8cce6117fd8dd3d592dfa18d7d290ea35a9 /arch/powerpc/sysdev | |
| parent | c424c108233dc422a9a29ee833154006a5bdf9fc (diff) | |
KVM: PPC: Book3S HV: Enable use of the new XIVE "single escalation" feature
That feature, provided by Power9 DD2.0 and later, when supported
by newer OPAL versions, allows us to sacrifice a queue (priority 7)
in favor of merging all the escalation interrupts of the queues
of a single VP into a single interrupt.
This reduces the number of host interrupts used up by KVM guests
especially when those guests use multiple priorities.
It will also enable a future change to control the masking of the
escalation interrupts more precisely to avoid spurious ones.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch/powerpc/sysdev')
| -rw-r--r-- | arch/powerpc/sysdev/xive/native.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c index ebc244b08d67..d22aeb0b69e1 100644 --- a/arch/powerpc/sysdev/xive/native.c +++ b/arch/powerpc/sysdev/xive/native.c @@ -42,6 +42,7 @@ static u32 xive_provision_chip_count; static u32 xive_queue_shift; static u32 xive_pool_vps = XIVE_INVALID_VP; static struct kmem_cache *xive_provision_cache; +static bool xive_has_single_esc; int xive_native_populate_irq_data(u32 hw_irq, struct xive_irq_data *data) { @@ -571,6 +572,10 @@ bool __init xive_native_init(void) break; } + /* Do we support single escalation */ + if (of_get_property(np, "single-escalation-support", NULL) != NULL) + xive_has_single_esc = true; + /* Configure Thread Management areas for KVM */ for_each_possible_cpu(cpu) kvmppc_set_xive_tima(cpu, r.start, tima); @@ -667,12 +672,15 @@ void xive_native_free_vp_block(u32 vp_base) } EXPORT_SYMBOL_GPL(xive_native_free_vp_block); -int xive_native_enable_vp(u32 vp_id) +int xive_native_enable_vp(u32 vp_id, bool single_escalation) { s64 rc; + u64 flags = OPAL_XIVE_VP_ENABLED; + if (single_escalation) + flags |= OPAL_XIVE_VP_SINGLE_ESCALATION; for (;;) { - rc = opal_xive_set_vp_info(vp_id, OPAL_XIVE_VP_ENABLED, 0); + rc = opal_xive_set_vp_info(vp_id, flags, 0); if (rc != OPAL_BUSY) break; msleep(1); @@ -710,3 +718,9 @@ int xive_native_get_vp_info(u32 vp_id, u32 *out_cam_id, u32 *out_chip_id) return 0; } EXPORT_SYMBOL_GPL(xive_native_get_vp_info); + +bool xive_native_has_single_escalation(void) +{ + return xive_has_single_esc; +} +EXPORT_SYMBOL_GPL(xive_native_has_single_escalation); |