Message ID | 1568197942-15374-5-git-send-email-andrii.anisov@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Changes to time accounting | expand |
Hi Andrii, Andrii Anisov writes: > From: Andrii Anisov <andrii_anisov@epam.com> > > Call time accounting hooks from appropriate transition points > of the ARM64 code. I'd prefer more elaborate commit message. For example - what are appropriate transition points? I mean - how you chose ones? > Signed-off-by: Andrii Anisov <andrii_anisov@epam.com> > --- > xen/arch/arm/arm64/entry.S | 39 ++++++++++++++++++++++++++++++++++++--- > xen/arch/arm/domain.c | 2 ++ > 2 files changed, 38 insertions(+), 3 deletions(-) > > diff --git a/xen/arch/arm/arm64/entry.S b/xen/arch/arm/arm64/entry.S > index 2d9a271..6fb2fa9 100644 > --- a/xen/arch/arm/arm64/entry.S > +++ b/xen/arch/arm/arm64/entry.S > @@ -143,12 +143,21 @@ > > .endm > > - .macro exit, hyp, compat > + .macro exit, hyp, compat, tacc=1 > > .if \hyp == 0 /* Guest mode */ > > + .if \tacc == 1 There is a hard tab, instead of 8 spaces. Also, while it is easy to guess what 'hyp' and 'compat' mean, it is hard to tell what 'tacc' stands for. I think, you need either better name for this or a comment, which explains all parameters. > + > + mov x0, #1 > + bl tacc_hyp > + > + .endif The same about hard tabs. Probably, there are more of them in this patch. > + > bl leave_hypervisor_tail /* Disables interrupts on return */ > > + mov x0, #1 > + bl tacc_guest > exit_guest \compat > > .endif > @@ -205,9 +214,15 @@ hyp_sync: > > hyp_irq: > entry hyp=1 > + mov x0,#5 Space is missing before #5 > + bl tacc_irq_enter > msr daifclr, #4 > mov x0, sp > bl do_trap_irq > + > + mov x0,#5 Space is missing before #5 > + bl tacc_irq_exit > + > exit hyp=1 > > guest_sync: > @@ -291,6 +306,9 @@ guest_sync_slowpath: > * to save them. > */ > entry hyp=0, compat=0, save_x0_x1=0 > + There are trailing whitespaces. I sure that 'git diff' highlights such mistakes... > + mov x0,#1 Space is missing before #1 > + bl tacc_gsync > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -307,6 +325,10 @@ guest_sync_slowpath: > > guest_irq: > entry hyp=0, compat=0 > + > + mov x0,#6 Space is missing before #6 > + bl tacc_irq_enter > + > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -319,6 +341,8 @@ guest_irq: > mov x0, sp > bl do_trap_irq > 1: > + mov x0,#6 Space is missing before #6, also looks like there is a hard tab character. > + bl tacc_irq_exit > exit hyp=0, compat=0 > > guest_fiq_invalid: > @@ -334,6 +358,9 @@ guest_error: > > guest_sync_compat: > entry hyp=0, compat=1 > + > + mov x0,#2 Space is missing before #2. > + bl tacc_gsync > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -350,6 +377,10 @@ guest_sync_compat: > > guest_irq_compat: > entry hyp=0, compat=1 > + > + mov x0,#7 Space is missing before #7. > + bl tacc_irq_enter > + > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -362,6 +393,8 @@ guest_irq_compat: > mov x0, sp > bl do_trap_irq > 1: > + mov x0,#7 Space is missing before #7... > + bl tacc_irq_exit > exit hyp=0, compat=1 > > guest_fiq_invalid_compat: > @@ -376,9 +409,9 @@ guest_error_compat: > exit hyp=0, compat=1 > > ENTRY(return_to_new_vcpu32) > - exit hyp=0, compat=1 > + exit hyp=0, compat=1, tacc=0 > ENTRY(return_to_new_vcpu64) > - exit hyp=0, compat=0 > + exit hyp=0, compat=0, tacc=0 > > return_from_trap: > msr daifset, #2 /* Mask interrupts */ > diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c > index a9c4113..53ef630 100644 > --- a/xen/arch/arm/domain.c > +++ b/xen/arch/arm/domain.c > @@ -51,11 +51,13 @@ static void do_idle(void) > process_pending_softirqs(); > > local_irq_disable(); > + tacc_idle(1); 1 and 2 (below) look like some magical values to me. I believe, you need to define some enumeration. > if ( cpu_is_haltable(cpu) ) > { > dsb(sy); > wfi(); > } > + tacc_hyp(2); > local_irq_enable(); > > sched_tick_resume(); -- Volodymyr Babchuk at EPAM
Hello Volodymyr, On 11.09.19 20:48, Volodymyr Babchuk wrote: > > Hi Andrii, > As we agreed, I'll wipe out debugging remains as well as cleanup coding style nits and resend the series.
On Thu, 12 Sep 2019, 13:10 Andrii Anisov, <andrii.anisov@gmail.com> wrote: > Hello Volodymyr, > > On 11.09.19 20:48, Volodymyr Babchuk wrote: > > > > Hi Andrii, > > > > As we agreed, I'll wipe out debugging remains as well as cleanup coding > style nits and resend the series. This an RFC and I am sure there current state is enough to spark a discussion. There are no need to waste time resending it and use filling up inboxes. Please wait for more time. Cheers, > -- > Sincerely, > Andrii Anisov. > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xenproject.org > https://lists.xenproject.org/mailman/listinfo/xen-devel
On 12.09.19 15:17, Julien Grall wrote: > This an RFC and I am sure there current state is enough to spark a discussion. There are no need to waste time resending it and use filling up inboxes. > > Please wait for more time. Gotcha!
(+ George and Dario) Hi, On 11/09/2019 11:32, Andrii Anisov wrote: > From: Andrii Anisov <andrii_anisov@epam.com> > > Call time accounting hooks from appropriate transition points > of the ARM64 code. > > Signed-off-by: Andrii Anisov <andrii_anisov@epam.com> > --- > xen/arch/arm/arm64/entry.S | 39 ++++++++++++++++++++++++++++++++++++--- > xen/arch/arm/domain.c | 2 ++ > 2 files changed, 38 insertions(+), 3 deletions(-) > > diff --git a/xen/arch/arm/arm64/entry.S b/xen/arch/arm/arm64/entry.S > index 2d9a271..6fb2fa9 100644 > --- a/xen/arch/arm/arm64/entry.S > +++ b/xen/arch/arm/arm64/entry.S > @@ -143,12 +143,21 @@ > > .endm > > - .macro exit, hyp, compat > + .macro exit, hyp, compat, tacc=1 > > .if \hyp == 0 /* Guest mode */ > > + .if \tacc == 1 This is here because you may already be in the HYP state, right? I noticed in the previous patch you mention that you only handle "re-entry" for the IRQ state. As you don't have "exit" for states other than IRQ, then I would not consider this is as re-entry. It is more like you transition from one state to another (it happen this is the same state). The problem of re-entry would be if you take an exception that is going to switch the state. But the concern would be exactly the same if you take an exception that switch the state (such as synchronous hypervisor exception). This raises the question, how do you account SError interrupt/synchronous exception? > + > + mov x0, #1 > + bl tacc_hyp > + > + .endif > + > bl leave_hypervisor_tail /* Disables interrupts on return */ As mentioned in the previous patch, leave_hypervisor_tail() may do some IO emulation that requires to be preemptible. So I don't think this is correct to get that time accounted to the hypervisor. > > + mov x0, #1 > + bl tacc_guest > exit_guest \compat > > .endif > @@ -205,9 +214,15 @@ hyp_sync: > > hyp_irq: > entry hyp=1 > + mov x0,#5 > + bl tacc_irq_enter > msr daifclr, #4 > mov x0, sp > bl do_trap_irq > + > + mov x0,#5 > + bl tacc_irq_exit > + > exit hyp=1 > > guest_sync: > @@ -291,6 +306,9 @@ guest_sync_slowpath: > * to save them. > */ > entry hyp=0, compat=0, save_x0_x1=0 > + > + mov x0,#1 > + bl tacc_gsync > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -307,6 +325,10 @@ guest_sync_slowpath: > > guest_irq: > entry hyp=0, compat=0 > + > + mov x0,#6 > + bl tacc_irq_enter > + > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -319,6 +341,8 @@ guest_irq: > mov x0, sp > bl do_trap_irq > 1: > + mov x0,#6 > + bl tacc_irq_exit > exit hyp=0, compat=0 > > guest_fiq_invalid: > @@ -334,6 +358,9 @@ guest_error: > > guest_sync_compat: > entry hyp=0, compat=1 > + > + mov x0,#2 > + bl tacc_gsync > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -350,6 +377,10 @@ guest_sync_compat: > > guest_irq_compat: > entry hyp=0, compat=1 > + > + mov x0,#7 > + bl tacc_irq_enter > + > /* > * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT > * is not set. If a vSError took place, the initial exception will be > @@ -362,6 +393,8 @@ guest_irq_compat: > mov x0, sp > bl do_trap_irq > 1: > + mov x0,#7 > + bl tacc_irq_exit > exit hyp=0, compat=1 > > guest_fiq_invalid_compat: > @@ -376,9 +409,9 @@ guest_error_compat: > exit hyp=0, compat=1 > > ENTRY(return_to_new_vcpu32) > - exit hyp=0, compat=1 > + exit hyp=0, compat=1, tacc=0 > ENTRY(return_to_new_vcpu64) > - exit hyp=0, compat=0 > + exit hyp=0, compat=0, tacc=0 > > return_from_trap: > msr daifset, #2 /* Mask interrupts */ > diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c > index a9c4113..53ef630 100644 > --- a/xen/arch/arm/domain.c > +++ b/xen/arch/arm/domain.c > @@ -51,11 +51,13 @@ static void do_idle(void) > process_pending_softirqs(); > > local_irq_disable(); > + tacc_idle(1); Any reason to call this before the if and not inside? > if ( cpu_is_haltable(cpu) ) > { > dsb(sy); > wfi(); > } > + tacc_hyp(2); > local_irq_enable(); > > sched_tick_resume(); > Cheers,
On 28.10.19 16:47, Julien Grall wrote: > (+ George and Dario) > > Hi, > > On 11/09/2019 11:32, Andrii Anisov wrote: >> From: Andrii Anisov <andrii_anisov@epam.com> >> >> Call time accounting hooks from appropriate transition points >> of the ARM64 code. >> >> Signed-off-by: Andrii Anisov <andrii_anisov@epam.com> >> --- >> xen/arch/arm/arm64/entry.S | 39 ++++++++++++++++++++++++++++++++++++--- >> xen/arch/arm/domain.c | 2 ++ >> 2 files changed, 38 insertions(+), 3 deletions(-) >> >> diff --git a/xen/arch/arm/arm64/entry.S b/xen/arch/arm/arm64/entry.S >> index 2d9a271..6fb2fa9 100644 >> --- a/xen/arch/arm/arm64/entry.S >> +++ b/xen/arch/arm/arm64/entry.S >> @@ -143,12 +143,21 @@ >> .endm >> - .macro exit, hyp, compat >> + .macro exit, hyp, compat, tacc=1 >> .if \hyp == 0 /* Guest mode */ >> + .if \tacc == 1 > > This is here because you may already be in the HYP state, right? > > I noticed in the previous patch you mention that you only handle "re-entry" for the IRQ state. > > As you don't have "exit" for states other than IRQ, then I would not consider this is as re-entry. It is more like you transition from one state to another (it happen this is the same state). > > The problem of re-entry would be if you take an exception that is going to switch the state. But the concern would be exactly the same if you take an exception that switch the state (such as synchronous hypervisor exception). > > This raises the question, how do you account SError interrupt/synchronous exception? Well, I guess I have to think more about it. Maybe I do not understand completely that problem now. > >> + >> + mov x0, #1 >> + bl tacc_hyp >> + >> + .endif >> + >> bl leave_hypervisor_tail /* Disables interrupts on return */ > > As mentioned in the previous patch, leave_hypervisor_tail() may do some IO emulation that requires to be preemptible. So I don't think this is correct to get that time accounted to the hypervisor. Could you please point me to the line of the code? Are you saying about GIC? > >> + mov x0, #1 >> + bl tacc_guest >> exit_guest \compat >> .endif >> @@ -205,9 +214,15 @@ hyp_sync: >> hyp_irq: >> entry hyp=1 >> + mov x0,#5 >> + bl tacc_irq_enter >> msr daifclr, #4 >> mov x0, sp >> bl do_trap_irq >> + >> + mov x0,#5 >> + bl tacc_irq_exit >> + >> exit hyp=1 >> guest_sync: >> @@ -291,6 +306,9 @@ guest_sync_slowpath: >> * to save them. >> */ >> entry hyp=0, compat=0, save_x0_x1=0 >> + >> + mov x0,#1 >> + bl tacc_gsync >> /* >> * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT >> * is not set. If a vSError took place, the initial exception will be >> @@ -307,6 +325,10 @@ guest_sync_slowpath: >> guest_irq: >> entry hyp=0, compat=0 >> + >> + mov x0,#6 >> + bl tacc_irq_enter >> + >> /* >> * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT >> * is not set. If a vSError took place, the initial exception will be >> @@ -319,6 +341,8 @@ guest_irq: >> mov x0, sp >> bl do_trap_irq >> 1: >> + mov x0,#6 >> + bl tacc_irq_exit >> exit hyp=0, compat=0 >> guest_fiq_invalid: >> @@ -334,6 +358,9 @@ guest_error: >> guest_sync_compat: >> entry hyp=0, compat=1 >> + >> + mov x0,#2 >> + bl tacc_gsync >> /* >> * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT >> * is not set. If a vSError took place, the initial exception will be >> @@ -350,6 +377,10 @@ guest_sync_compat: >> guest_irq_compat: >> entry hyp=0, compat=1 >> + >> + mov x0,#7 >> + bl tacc_irq_enter >> + >> /* >> * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT >> * is not set. If a vSError took place, the initial exception will be >> @@ -362,6 +393,8 @@ guest_irq_compat: >> mov x0, sp >> bl do_trap_irq >> 1: >> + mov x0,#7 >> + bl tacc_irq_exit >> exit hyp=0, compat=1 >> guest_fiq_invalid_compat: >> @@ -376,9 +409,9 @@ guest_error_compat: >> exit hyp=0, compat=1 >> ENTRY(return_to_new_vcpu32) >> - exit hyp=0, compat=1 >> + exit hyp=0, compat=1, tacc=0 >> ENTRY(return_to_new_vcpu64) >> - exit hyp=0, compat=0 >> + exit hyp=0, compat=0, tacc=0 >> return_from_trap: >> msr daifset, #2 /* Mask interrupts */ >> diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c >> index a9c4113..53ef630 100644 >> --- a/xen/arch/arm/domain.c >> +++ b/xen/arch/arm/domain.c >> @@ -51,11 +51,13 @@ static void do_idle(void) >> process_pending_softirqs(); >> local_irq_disable(); >> + tacc_idle(1); > > Any reason to call this before the if and not inside? Maybe having at least a bit of idle for non-haltable cpu. But from the second thought it would not work. > >> if ( cpu_is_haltable(cpu) ) >> { >> dsb(sy); >> wfi(); >> } >> + tacc_hyp(2); >> local_irq_enable(); >> sched_tick_resume(); >> > > Cheers, >
diff --git a/xen/arch/arm/arm64/entry.S b/xen/arch/arm/arm64/entry.S index 2d9a271..6fb2fa9 100644 --- a/xen/arch/arm/arm64/entry.S +++ b/xen/arch/arm/arm64/entry.S @@ -143,12 +143,21 @@ .endm - .macro exit, hyp, compat + .macro exit, hyp, compat, tacc=1 .if \hyp == 0 /* Guest mode */ + .if \tacc == 1 + + mov x0, #1 + bl tacc_hyp + + .endif + bl leave_hypervisor_tail /* Disables interrupts on return */ + mov x0, #1 + bl tacc_guest exit_guest \compat .endif @@ -205,9 +214,15 @@ hyp_sync: hyp_irq: entry hyp=1 + mov x0,#5 + bl tacc_irq_enter msr daifclr, #4 mov x0, sp bl do_trap_irq + + mov x0,#5 + bl tacc_irq_exit + exit hyp=1 guest_sync: @@ -291,6 +306,9 @@ guest_sync_slowpath: * to save them. */ entry hyp=0, compat=0, save_x0_x1=0 + + mov x0,#1 + bl tacc_gsync /* * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT * is not set. If a vSError took place, the initial exception will be @@ -307,6 +325,10 @@ guest_sync_slowpath: guest_irq: entry hyp=0, compat=0 + + mov x0,#6 + bl tacc_irq_enter + /* * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT * is not set. If a vSError took place, the initial exception will be @@ -319,6 +341,8 @@ guest_irq: mov x0, sp bl do_trap_irq 1: + mov x0,#6 + bl tacc_irq_exit exit hyp=0, compat=0 guest_fiq_invalid: @@ -334,6 +358,9 @@ guest_error: guest_sync_compat: entry hyp=0, compat=1 + + mov x0,#2 + bl tacc_gsync /* * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT * is not set. If a vSError took place, the initial exception will be @@ -350,6 +377,10 @@ guest_sync_compat: guest_irq_compat: entry hyp=0, compat=1 + + mov x0,#7 + bl tacc_irq_enter + /* * The vSError will be checked while SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT * is not set. If a vSError took place, the initial exception will be @@ -362,6 +393,8 @@ guest_irq_compat: mov x0, sp bl do_trap_irq 1: + mov x0,#7 + bl tacc_irq_exit exit hyp=0, compat=1 guest_fiq_invalid_compat: @@ -376,9 +409,9 @@ guest_error_compat: exit hyp=0, compat=1 ENTRY(return_to_new_vcpu32) - exit hyp=0, compat=1 + exit hyp=0, compat=1, tacc=0 ENTRY(return_to_new_vcpu64) - exit hyp=0, compat=0 + exit hyp=0, compat=0, tacc=0 return_from_trap: msr daifset, #2 /* Mask interrupts */ diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c index a9c4113..53ef630 100644 --- a/xen/arch/arm/domain.c +++ b/xen/arch/arm/domain.c @@ -51,11 +51,13 @@ static void do_idle(void) process_pending_softirqs(); local_irq_disable(); + tacc_idle(1); if ( cpu_is_haltable(cpu) ) { dsb(sy); wfi(); } + tacc_hyp(2); local_irq_enable(); sched_tick_resume();