qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Harsh Prateek Bora <harshpb@linux.ibm.com>
To: Nicholas Piggin <npiggin@gmail.com>, qemu-ppc@nongnu.org
Cc: "Caleb Schlossin" <calebs@linux.vnet.ibm.com>,
	"Cédric Le Goater" <clg@kaod.org>,
	"Frédéric Barrat" <fbarrat@linux.ibm.com>,
	"Daniel Henrique Barboza" <danielhb413@gmail.com>,
	qemu-devel@nongnu.org
Subject: Re: [RFC PATCH 07/10] target/ppc: Add helpers to check for SMT sibling threads
Date: Tue, 28 May 2024 14:46:40 +0530	[thread overview]
Message-ID: <1f9c8eb6-aa4f-4740-89a6-20b510b21d7d@linux.ibm.com> (raw)
In-Reply-To: <20240526122612.473476-8-npiggin@gmail.com>



On 5/26/24 17:56, Nicholas Piggin wrote:
> Add helpers for TCG code to determine if there are SMT siblings
> sharing per-core and per-lpar registers. This simplifies the
> callers and makes SMT register topology simpler to modify with
> later changes.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>   target/ppc/cpu.h             |  7 +++++++
>   target/ppc/cpu_init.c        |  2 +-
>   target/ppc/excp_helper.c     | 16 +++++++---------
>   target/ppc/misc_helper.c     | 27 ++++++---------------------
>   target/ppc/timebase_helper.c | 20 +++++++-------------
>   5 files changed, 28 insertions(+), 44 deletions(-)
> 
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index 9a89083932..8fd6ade471 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -1406,6 +1406,13 @@ struct CPUArchState {
>       uint64_t pmu_base_time;
>   };
>   
> +#define PPC_CPU_HAS_CORE_SIBLINGS(cs)                           \
> +    (cs->nr_threads > 1)
> +
> +#define PPC_CPU_HAS_LPAR_SIBLINGS(cs)                           \
> +    ((POWERPC_CPU(cs)->env.flags & POWERPC_FLAG_SMT_1LPAR) &&   \
> +     PPC_CPU_HAS_CORE_SIBLINGS(cs))
> +
>   #define _CORE_ID(cs)                                            \
>       (POWERPC_CPU(cs)->env.core_index)
>   
> diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
> index ae483e20c4..e71ee008ed 100644
> --- a/target/ppc/cpu_init.c
> +++ b/target/ppc/cpu_init.c
> @@ -6975,7 +6975,7 @@ static void ppc_cpu_realize(DeviceState *dev, Error **errp)
>   
>       pcc->parent_realize(dev, errp);
>   
> -    if (env_cpu(env)->nr_threads > 1) {
> +    if (PPC_CPU_HAS_CORE_SIBLINGS(cs)) {
>           env->flags |= POWERPC_FLAG_SMT;
>       }
>   
> diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
> index 0cd542675f..fd45da0f2b 100644
> --- a/target/ppc/excp_helper.c
> +++ b/target/ppc/excp_helper.c
> @@ -3029,7 +3029,7 @@ void helper_book3s_msgsnd(CPUPPCState *env, target_ulong rb)
>           brdcast = true;
>       }
>   
> -    if (cs->nr_threads == 1 || !brdcast) {
> +    if (!PPC_CPU_HAS_CORE_SIBLINGS(cs) || !brdcast) {

Since there are multiple usage of above macro in negation below as well, 
we may probably want to introduce another macro PPC_CPU_HAS_SINGLE_CORE
which checks only for nr_threads == 1. Anyways,

Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>


>           ppc_set_irq(cpu, PPC_INTERRUPT_HDOORBELL, 1);
>           return;
>       }
> @@ -3067,21 +3067,19 @@ void helper_book3s_msgsndp(CPUPPCState *env, target_ulong rb)
>       CPUState *cs = env_cpu(env);
>       PowerPCCPU *cpu = env_archcpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>       int ttir = rb & PPC_BITMASK(57, 63);
>   
>       helper_hfscr_facility_check(env, HFSCR_MSGP, "msgsndp", HFSCR_IC_MSGP);
>   
> -    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> -        nr_threads = 1; /* msgsndp behaves as 1-thread in LPAR-per-thread mode*/
> -    }
> -
> -    if (!dbell_type_server(rb) || ttir >= nr_threads) {
> +    if (!dbell_type_server(rb)) {
>           return;
>       }
>   
> -    if (nr_threads == 1) {
> -        ppc_set_irq(cpu, PPC_INTERRUPT_DOORBELL, 1);
> +    /* msgsndp behaves as 1-thread in LPAR-per-thread mode*/
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
> +        if (ttir == 0) {
> +            ppc_set_irq(cpu, PPC_INTERRUPT_DOORBELL, 1);
> +        }
>           return;
>       }
>   
> diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
> index 46ba3a5584..598c956cdd 100644
> --- a/target/ppc/misc_helper.c
> +++ b/target/ppc/misc_helper.c
> @@ -49,9 +49,8 @@ void helper_spr_core_write_generic(CPUPPCState *env, uint32_t sprn,
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1) {
> +    if (!PPC_CPU_HAS_CORE_SIBLINGS(cs)) {
>           env->spr[sprn] = val;
>           return;
>       }
> @@ -196,7 +195,7 @@ void helper_store_ptcr(CPUPPCState *env, target_ulong val)
>               return;
>           }
>   
> -        if (cs->nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +        if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>               env->spr[SPR_PTCR] = val;
>               tlb_flush(cs);
>           } else {
> @@ -243,16 +242,12 @@ target_ulong helper_load_dpdes(CPUPPCState *env)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>       target_ulong dpdes = 0;
>   
>       helper_hfscr_facility_check(env, HFSCR_MSGP, "load DPDES", HFSCR_IC_MSGP);
>   
> -    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> -        nr_threads = 1; /* DPDES behaves as 1-thread in LPAR-per-thread mode */
> -    }
> -
> -    if (nr_threads == 1) {
> +    /* DPDES behaves as 1-thread in LPAR-per-thread mode */
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           if (env->pending_interrupts & PPC_INTERRUPT_DOORBELL) {
>               dpdes = 1;
>           }
> @@ -279,21 +274,11 @@ void helper_store_dpdes(CPUPPCState *env, target_ulong val)
>       PowerPCCPU *cpu = env_archcpu(env);
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
>       helper_hfscr_facility_check(env, HFSCR_MSGP, "store DPDES", HFSCR_IC_MSGP);
>   
> -    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> -        nr_threads = 1; /* DPDES behaves as 1-thread in LPAR-per-thread mode */
> -    }
> -
> -    if (val & ~(nr_threads - 1)) {
> -        qemu_log_mask(LOG_GUEST_ERROR, "Invalid DPDES register value "
> -                      TARGET_FMT_lx"\n", val);
> -        val &= (nr_threads - 1); /* Ignore the invalid bits */
> -    }
> -
> -    if (nr_threads == 1) {
> +    /* DPDES behaves as 1-thread in LPAR-per-thread mode */
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           ppc_set_irq(cpu, PPC_INTERRUPT_DOORBELL, val & 0x1);
>           return;
>       }
> diff --git a/target/ppc/timebase_helper.c b/target/ppc/timebase_helper.c
> index 788c498d63..abe7b95696 100644
> --- a/target/ppc/timebase_helper.c
> +++ b/target/ppc/timebase_helper.c
> @@ -63,9 +63,8 @@ void helper_store_purr(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_purr(env, val);
>           return;
>       }
> @@ -82,9 +81,8 @@ void helper_store_tbl(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_tbl(env, val);
>           return;
>       }
> @@ -99,9 +97,8 @@ void helper_store_tbu(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_tbu(env, val);
>           return;
>       }
> @@ -141,9 +138,8 @@ void helper_store_hdecr(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_hdecr(env, val);
>           return;
>       }
> @@ -158,9 +154,8 @@ void helper_store_vtb(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_vtb(env, val);
>           return;
>       }
> @@ -175,9 +170,8 @@ void helper_store_tbu40(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>       CPUState *ccs;
> -    uint32_t nr_threads = cs->nr_threads;
>   
> -    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
> +    if (!PPC_CPU_HAS_LPAR_SIBLINGS(cs)) {
>           cpu_ppc_store_tbu40(env, val);
>           return;
>       }
> @@ -288,7 +282,7 @@ static void write_tfmr(CPUPPCState *env, target_ulong val)
>   {
>       CPUState *cs = env_cpu(env);
>   
> -    if (cs->nr_threads == 1) {
> +    if (!PPC_CPU_HAS_CORE_SIBLINGS(cs)) {
>           env->spr[SPR_TFMR] = val;
>       } else {
>           CPUState *ccs;


  reply	other threads:[~2024-05-28  9:17 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-26 12:26 [RFC PATCH 00/10] ppc/pnv: Better big-core model, lpar-per-core, PC unit Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 01/10] ppc/pnv: Add pointer from PnvCPUState to PnvCore Nicholas Piggin
2024-05-27 15:23   ` Cédric Le Goater
2024-05-28  6:19   ` Harsh Prateek Bora
2024-05-26 12:26 ` [RFC PATCH 02/10] ppc/pnv: Move timebase state into PnvCore Nicholas Piggin
2024-05-28  6:28   ` Harsh Prateek Bora
2024-05-28  7:52     ` Cédric Le Goater
2024-05-29  0:19       ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 03/10] target/ppc: Improve SPR indirect registers Nicholas Piggin
2024-05-28  6:50   ` Harsh Prateek Bora
2024-05-29  0:13     ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 04/10] ppc/pnv: specialise init for powernv8/9/10 machines Nicholas Piggin
2024-05-28  7:10   ` Harsh Prateek Bora
2024-05-28  7:45     ` Cédric Le Goater
2024-05-29  0:18       ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 05/10] ppc/pnv: Extend chip_pir class method to TIR as well Nicholas Piggin
2024-05-28  8:32   ` Harsh Prateek Bora
2024-05-29  0:24     ` Nicholas Piggin
2024-05-29  6:30       ` Cédric Le Goater
2024-05-30  6:38         ` Nicholas Piggin
2024-05-30  6:42           ` Cédric Le Goater
2024-05-26 12:26 ` [RFC PATCH 06/10] ppc: Add a core_index to CPUPPCState for SMT vCPUs Nicholas Piggin
2024-05-28  8:48   ` Harsh Prateek Bora
2024-05-28  8:52     ` Harsh Prateek Bora
2024-05-29  0:28       ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 07/10] target/ppc: Add helpers to check for SMT sibling threads Nicholas Piggin
2024-05-28  9:16   ` Harsh Prateek Bora [this message]
2024-05-29  0:31     ` Nicholas Piggin
2024-05-29  6:34   ` Cédric Le Goater
2024-05-30  6:38     ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 08/10] ppc/pnv: Invert the design for big-core machine modelling Nicholas Piggin
2024-05-29  6:57   ` Cédric Le Goater
2024-05-30  6:52     ` Nicholas Piggin
2024-05-30  7:46       ` Cédric Le Goater
2024-06-03  5:22         ` Nicholas Piggin
2024-05-29 10:49   ` Harsh Prateek Bora
2024-05-26 12:26 ` [RFC PATCH 09/10] ppc/pnv: Implement POWER10 PC xscom registers for direct controls Nicholas Piggin
2024-05-29  7:00   ` Cédric Le Goater
2024-05-30  6:53     ` Nicholas Piggin
2024-05-26 12:26 ` [RFC PATCH 10/10] ppc/pnv: Add an LPAR per core machine option Nicholas Piggin
2024-05-29  7:02   ` Cédric Le Goater
2024-05-27  6:25 ` [RFC PATCH 00/10] ppc/pnv: Better big-core model, lpar-per-core, PC unit Cédric Le Goater
2024-05-27  7:32   ` Nicholas Piggin
2024-05-27  7:36     ` Cédric Le Goater

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1f9c8eb6-aa4f-4740-89a6-20b510b21d7d@linux.ibm.com \
    --to=harshpb@linux.ibm.com \
    --cc=calebs@linux.vnet.ibm.com \
    --cc=clg@kaod.org \
    --cc=danielhb413@gmail.com \
    --cc=fbarrat@linux.ibm.com \
    --cc=npiggin@gmail.com \
    --cc=qemu-devel@nongnu.org \
    --cc=qemu-ppc@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).