Re: [PATCH v3 03/10] powerpc/pseries/vas: Save LPID in pseries_vas_window struct

2022-02-15 Thread Haren Myneni 
On Mon, 2022-02-14 at 12:41 +1000, Nicholas Piggin wrote:
> Excerpts from Haren Myneni's message of January 22, 2022 5:55 am:
> > The kernel sets the VAS window with partition PID when is opened in
> > the hypervisor. During DLPAR operation, windows can be closed and
> > reopened in the hypervisor when the credit is available. So saves
> > this PID in pseries_vas_window struct when the window is opened
> > initially and reuse it later during DLPAR operation.
> 
> This probably shouldn't be called lpid, while you're changing it.
> "partition PID" and "LPAR PID" is also confusing. I know the name
> somewhat comes from the specifiction, but pid/PID would be fine,
> it's clear we are talking about "this LPAR" when in pseries code.
> 
> > Signed-off-by: Haren Myneni 
> > ---
> >  arch/powerpc/platforms/pseries/vas.c | 7 ---
> >  arch/powerpc/platforms/pseries/vas.h | 1 +
> >  2 files changed, 5 insertions(+), 3 deletions(-)
> > 
> > diff --git a/arch/powerpc/platforms/pseries/vas.c
> > b/arch/powerpc/platforms/pseries/vas.c
> > index d2c8292bfb33..2ef56157634f 100644
> > --- a/arch/powerpc/platforms/pseries/vas.c
> > +++ b/arch/powerpc/platforms/pseries/vas.c
> > @@ -107,7 +107,6 @@ static int h_deallocate_vas_window(u64 winid)
> >  static int h_modify_vas_window(struct pseries_vas_window *win)
> >  {
> > long rc;
> > -   u32 lpid = mfspr(SPRN_PID);
> >  
> > /*
> >  * AMR value is not supported in Linux VAS implementation.
> > @@ -115,7 +114,7 @@ static int h_modify_vas_window(struct
> > pseries_vas_window *win)
> >  */
> > do {
> > rc = plpar_hcall_norets(H_MODIFY_VAS_WINDOW,
> > -   win->vas_win.winid, lpid, 0,
> > +   win->vas_win.winid, win->lpid,
> > 0,
> > VAS_MOD_WIN_FLAGS, 0);
> >  
> > rc = hcall_return_busy_check(rc);
> > @@ -125,7 +124,7 @@ static int h_modify_vas_window(struct
> > pseries_vas_window *win)
> > return 0;
> >  
> > pr_err("H_MODIFY_VAS_WINDOW error: %ld, winid %u lpid %u\n",
> > -   rc, win->vas_win.winid, lpid);
> > +   rc, win->vas_win.winid, win->lpid);
> > return -EIO;
> >  }
> >  
> > @@ -338,6 +337,8 @@ static struct vas_window
> > *vas_allocate_window(int
> > vas_id, u64 flags,
> > }
> > }
> >  
> > +   txwin->lpid = mfspr(SPRN_PID);
> > +
> > /*
> >  * Allocate / Deallocate window hcalls and setup / free IRQs
> >  * have to be protected with mutex.
> > diff --git a/arch/powerpc/platforms/pseries/vas.h
> > b/arch/powerpc/platforms/pseries/vas.h
> > index fa7ce74f1e49..0538760d13be 100644
> > --- a/arch/powerpc/platforms/pseries/vas.h
> > +++ b/arch/powerpc/platforms/pseries/vas.h
> > @@ -115,6 +115,7 @@ struct pseries_vas_window {
> > u64 domain[6];  /* Associativity domain Ids */
> > /* this window is allocated */
> > u64 util;
> > +   u32 lpid;
> 
> Comment could be "PID associated with this window".   

yes, will add this comment.

> 
> BTW, is the TID parameter deprecated? Doesn't seem that we use that.

Right, tpid is deprecated on p10 and we are not using it.

Thanks
Haren

> 
> Thanks,
> Nick

Re: [PATCH v3 03/10] powerpc/pseries/vas: Save LPID in pseries_vas_window struct

2022-02-13 Thread Nicholas Piggin 
Excerpts from Haren Myneni's message of January 22, 2022 5:55 am:
> 
> The kernel sets the VAS window with partition PID when is opened in
> the hypervisor. During DLPAR operation, windows can be closed and
> reopened in the hypervisor when the credit is available. So saves
> this PID in pseries_vas_window struct when the window is opened
> initially and reuse it later during DLPAR operation.

This probably shouldn't be called lpid, while you're changing it.
"partition PID" and "LPAR PID" is also confusing. I know the name
somewhat comes from the specifiction, but pid/PID would be fine,
it's clear we are talking about "this LPAR" when in pseries code.

> 
> Signed-off-by: Haren Myneni 
> ---
>  arch/powerpc/platforms/pseries/vas.c | 7 ---
>  arch/powerpc/platforms/pseries/vas.h | 1 +
>  2 files changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/pseries/vas.c
> b/arch/powerpc/platforms/pseries/vas.c
> index d2c8292bfb33..2ef56157634f 100644
> --- a/arch/powerpc/platforms/pseries/vas.c
> +++ b/arch/powerpc/platforms/pseries/vas.c
> @@ -107,7 +107,6 @@ static int h_deallocate_vas_window(u64 winid)
>  static int h_modify_vas_window(struct pseries_vas_window *win)
>  {
>   long rc;
> - u32 lpid = mfspr(SPRN_PID);
>  
>   /*
>* AMR value is not supported in Linux VAS implementation.
> @@ -115,7 +114,7 @@ static int h_modify_vas_window(struct
> pseries_vas_window *win)
>*/
>   do {
>   rc = plpar_hcall_norets(H_MODIFY_VAS_WINDOW,
> - win->vas_win.winid, lpid, 0,
> + win->vas_win.winid, win->lpid,
> 0,
>   VAS_MOD_WIN_FLAGS, 0);
>  
>   rc = hcall_return_busy_check(rc);
> @@ -125,7 +124,7 @@ static int h_modify_vas_window(struct
> pseries_vas_window *win)
>   return 0;
>  
>   pr_err("H_MODIFY_VAS_WINDOW error: %ld, winid %u lpid %u\n",
> - rc, win->vas_win.winid, lpid);
> + rc, win->vas_win.winid, win->lpid);
>   return -EIO;
>  }
>  
> @@ -338,6 +337,8 @@ static struct vas_window *vas_allocate_window(int
> vas_id, u64 flags,
>   }
>   }
>  
> + txwin->lpid = mfspr(SPRN_PID);
> +
>   /*
>* Allocate / Deallocate window hcalls and setup / free IRQs
>* have to be protected with mutex.
> diff --git a/arch/powerpc/platforms/pseries/vas.h
> b/arch/powerpc/platforms/pseries/vas.h
> index fa7ce74f1e49..0538760d13be 100644
> --- a/arch/powerpc/platforms/pseries/vas.h
> +++ b/arch/powerpc/platforms/pseries/vas.h
> @@ -115,6 +115,7 @@ struct pseries_vas_window {
>   u64 domain[6];  /* Associativity domain Ids */
>   /* this window is allocated */
>   u64 util;
> + u32 lpid;

Comment could be "PID associated with this window".

BTW, is the TID parameter deprecated? Doesn't seem that we use that.

Thanks,
Nick

[PATCH v3 03/10] powerpc/pseries/vas: Save LPID in pseries_vas_window struct

2022-01-21 Thread Haren Myneni 


The kernel sets the VAS window with partition PID when is opened in
the hypervisor. During DLPAR operation, windows can be closed and
reopened in the hypervisor when the credit is available. So saves
this PID in pseries_vas_window struct when the window is opened
initially and reuse it later during DLPAR operation.

Signed-off-by: Haren Myneni 
---
 arch/powerpc/platforms/pseries/vas.c | 7 ---
 arch/powerpc/platforms/pseries/vas.h | 1 +
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/vas.c
b/arch/powerpc/platforms/pseries/vas.c
index d2c8292bfb33..2ef56157634f 100644
--- a/arch/powerpc/platforms/pseries/vas.c
+++ b/arch/powerpc/platforms/pseries/vas.c
@@ -107,7 +107,6 @@ static int h_deallocate_vas_window(u64 winid)
 static int h_modify_vas_window(struct pseries_vas_window *win)
 {
long rc;
-   u32 lpid = mfspr(SPRN_PID);
 
/*
 * AMR value is not supported in Linux VAS implementation.
@@ -115,7 +114,7 @@ static int h_modify_vas_window(struct
pseries_vas_window *win)
 */
do {
rc = plpar_hcall_norets(H_MODIFY_VAS_WINDOW,
-   win->vas_win.winid, lpid, 0,
+   win->vas_win.winid, win->lpid,
0,
VAS_MOD_WIN_FLAGS, 0);
 
rc = hcall_return_busy_check(rc);
@@ -125,7 +124,7 @@ static int h_modify_vas_window(struct
pseries_vas_window *win)
return 0;
 
pr_err("H_MODIFY_VAS_WINDOW error: %ld, winid %u lpid %u\n",
-   rc, win->vas_win.winid, lpid);
+   rc, win->vas_win.winid, win->lpid);
return -EIO;
 }
 
@@ -338,6 +337,8 @@ static struct vas_window *vas_allocate_window(int
vas_id, u64 flags,
}
}
 
+   txwin->lpid = mfspr(SPRN_PID);
+
/*
 * Allocate / Deallocate window hcalls and setup / free IRQs
 * have to be protected with mutex.
diff --git a/arch/powerpc/platforms/pseries/vas.h
b/arch/powerpc/platforms/pseries/vas.h
index fa7ce74f1e49..0538760d13be 100644
--- a/arch/powerpc/platforms/pseries/vas.h
+++ b/arch/powerpc/platforms/pseries/vas.h
@@ -115,6 +115,7 @@ struct pseries_vas_window {
u64 domain[6];  /* Associativity domain Ids */
/* this window is allocated */
u64 util;
+   u32 lpid;
 
/* List of windows opened which is used for LPM */
struct list_head win_list;
-- 
2.27.0