linux-kernel - Re: [PATCH v3 2/3] powerpc/powernv/idle: Rename pnv_first_spr_loss

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1595202681.bt4670u7q7.astroid@bobo.none>
Date:   Mon, 20 Jul 2020 09:57:41 +1000
From:   Nicholas Piggin <npiggin@...il.com>
To:     benh@...nel.crashing.org, ego@...ux.vnet.ibm.com,
        linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        mikey@...ling.org, mpe@...erman.id.au, paulus@...ba.org,
        pratik.r.sampat@...il.com,
        Pratik Rajesh Sampat <psampat@...ux.ibm.com>,
        svaidy@...ux.ibm.com
Subject: Re: [PATCH v3 2/3] powerpc/powernv/idle: Rename
 pnv_first_spr_loss_level variable

Excerpts from Pratik Rajesh Sampat's message of July 18, 2020 4:53 am:
> Replace the variable name from using "pnv_first_spr_loss_level" to
> "pnv_first_fullstate_loss_level".
> 
> As pnv_first_spr_loss_level is supposed to be the earliest state that
> has OPAL_PM_LOSE_FULL_CONTEXT set, however as shallow states too loose
> SPR values, render an incorrect terminology.

It also doesn't lose "full" state at this loss level though. From the 
architecture it could be called "hv state loss level", but in POWER10 
even that is not strictly true.


> 
> Signed-off-by: Pratik Rajesh Sampat <psampat@...ux.ibm.com>
> ---
>  arch/powerpc/platforms/powernv/idle.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
> index f62904f70fc6..d439e11af101 100644
> --- a/arch/powerpc/platforms/powernv/idle.c
> +++ b/arch/powerpc/platforms/powernv/idle.c
> @@ -48,7 +48,7 @@ static bool default_stop_found;
>   * First stop state levels when SPR and TB loss can occur.
>   */
>  static u64 pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
> -static u64 pnv_first_spr_loss_level = MAX_STOP_STATE + 1;
> +static u64 pnv_first_fullstate_loss_level = MAX_STOP_STATE + 1;
>  
>  /*
>   * psscr value and mask of the deepest stop idle state.
> @@ -657,7 +657,7 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
>  		  */
>  		mmcr0		= mfspr(SPRN_MMCR0);
>  	}
> -	if ((psscr & PSSCR_RL_MASK) >= pnv_first_spr_loss_level) {
> +	if ((psscr & PSSCR_RL_MASK) >= pnv_first_fullstate_loss_level) {
>  		sprs.lpcr	= mfspr(SPRN_LPCR);
>  		sprs.hfscr	= mfspr(SPRN_HFSCR);
>  		sprs.fscr	= mfspr(SPRN_FSCR);
> @@ -741,7 +741,7 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
>  	 * just always test PSSCR for SPR/TB state loss.
>  	 */
>  	pls = (psscr & PSSCR_PLS) >> PSSCR_PLS_SHIFT;
> -	if (likely(pls < pnv_first_spr_loss_level)) {
> +	if (likely(pls < pnv_first_fullstate_loss_level)) {
>  		if (sprs_saved)
>  			atomic_stop_thread_idle();
>  		goto out;
> @@ -1088,7 +1088,7 @@ static void __init pnv_power9_idle_init(void)
>  	 * the deepest loss-less (OPAL_PM_STOP_INST_FAST) stop state.
>  	 */
>  	pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
> -	pnv_first_spr_loss_level = MAX_STOP_STATE + 1;
> +	pnv_first_fullstate_loss_level = MAX_STOP_STATE + 1;
>  	for (i = 0; i < nr_pnv_idle_states; i++) {
>  		int err;
>  		struct pnv_idle_states_t *state = &pnv_idle_states[i];
> @@ -1099,8 +1099,8 @@ static void __init pnv_power9_idle_init(void)
>  			pnv_first_tb_loss_level = psscr_rl;
>  
>  		if ((state->flags & OPAL_PM_LOSE_FULL_CONTEXT) &&
> -		     (pnv_first_spr_loss_level > psscr_rl))
> -			pnv_first_spr_loss_level = psscr_rl;
> +		     (pnv_first_fullstate_loss_level > psscr_rl))
> +			pnv_first_fullstate_loss_level = psscr_rl;
>  
>  		/*
>  		 * The idle code does not deal with TB loss occurring
> @@ -1111,8 +1111,8 @@ static void __init pnv_power9_idle_init(void)
>  		 * compatibility.
>  		 */
>  		if ((state->flags & OPAL_PM_TIMEBASE_STOP) &&
> -		     (pnv_first_spr_loss_level > psscr_rl))
> -			pnv_first_spr_loss_level = psscr_rl;
> +		     (pnv_first_fullstate_loss_level > psscr_rl))
> +			pnv_first_fullstate_loss_level = psscr_rl;
>  
>  		err = validate_psscr_val_mask(&state->psscr_val,
>  					      &state->psscr_mask,
> @@ -1158,7 +1158,7 @@ static void __init pnv_power9_idle_init(void)
>  	}
>  
>  	pr_info("cpuidle-powernv: First stop level that may lose SPRs = 0x%llx\n",
> -		pnv_first_spr_loss_level);
> +		pnv_first_fullstate_loss_level);
>  
>  	pr_info("cpuidle-powernv: First stop level that may lose timebase = 0x%llx\n",
>  		pnv_first_tb_loss_level);
> -- 
> 2.25.4
> 
>