diff options
| author | Paul Mackerras <paulus@samba.org> | 2015-03-28 06:21:06 +0300 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2015-04-21 16:21:32 +0300 |
| commit | 5d5b99cd6818bdbea287d23ef055bba1a8a9e648 (patch) | |
| tree | 1696dcf7ad7f1e566611093e18a387711c80aab7 /arch/powerpc/kvm/book3s_hv_rmhandlers.S | |
| parent | 25fedfca94cfbf2461314c6c34ef58e74a31b025 (diff) | |
| download | linux-5d5b99cd6818bdbea287d23ef055bba1a8a9e648.tar.xz | |
KVM: PPC: Book3S HV: Get rid of vcore nap_count and n_woken
We can tell when a secondary thread has finished running a guest by
the fact that it clears its kvm_hstate.kvm_vcpu pointer, so there
is no real need for the nap_count field in the kvmppc_vcore struct.
This changes kvmppc_wait_for_nap to poll the kvm_hstate.kvm_vcpu
pointers of the secondary threads rather than polling vc->nap_count.
Besides reducing the size of the kvmppc_vcore struct by 8 bytes,
this also means that we can tell which secondary threads have got
stuck and thus print a more informative error message.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_rmhandlers.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 19 |
1 files changed, 7 insertions, 12 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index f8267e5b3a50..6716db3f1a2b 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -292,26 +292,21 @@ kvm_secondary_got_guest: ld r6, PACA_DSCR(r13) std r6, HSTATE_DSCR(r13) + /* Order load of vcore, ptid etc. after load of vcpu */ + lwsync bl kvmppc_hv_entry /* Back from the guest, go back to nap */ /* Clear our vcpu pointer so we don't come back in early */ li r0, 0 - std r0, HSTATE_KVM_VCPU(r13) /* - * Make sure we clear HSTATE_KVM_VCPU(r13) before incrementing - * the nap_count, because once the increment to nap_count is - * visible we could be given another vcpu. + * Once we clear HSTATE_KVM_VCPU(r13), the code in + * kvmppc_run_core() is going to assume that all our vcpu + * state is visible in memory. This lwsync makes sure + * that that is true. */ lwsync - - /* increment the nap count and then go to nap mode */ - ld r4, HSTATE_KVM_VCORE(r13) - addi r4, r4, VCORE_NAP_COUNT -51: lwarx r3, 0, r4 - addi r3, r3, 1 - stwcx. r3, 0, r4 - bne 51b + std r0, HSTATE_KVM_VCPU(r13) /* * At this point we have finished executing in the guest. |