Excerpts from Haren Myneni's message of February 20, 2022 5:55 am:
>
> The kernel sets the VAS window with PID when it 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.
Thanks for renaming it lpid->pid and adding the comment.
Reviewed-by: Nicholas Piggin <npig...@gmail.com>
>
> Signed-off-by: Haren Myneni <ha...@linux.ibm.com>
> ---
> arch/powerpc/platforms/pseries/vas.c | 9 +++++----
> arch/powerpc/platforms/pseries/vas.h | 1 +
> 2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/vas.c
> b/arch/powerpc/platforms/pseries/vas.c
> index 18aae037ffe9..1035446f985b 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->pid, 0,
> VAS_MOD_WIN_FLAGS, 0);
>
> rc = hcall_return_busy_check(rc);
> @@ -124,8 +123,8 @@ static int h_modify_vas_window(struct pseries_vas_window
> *win)
> if (rc == H_SUCCESS)
> return 0;
>
> - pr_err("H_MODIFY_VAS_WINDOW error: %ld, winid %u lpid %u\n",
> - rc, win->vas_win.winid, lpid);
> + pr_err("H_MODIFY_VAS_WINDOW error: %ld, winid %u pid %u\n",
> + rc, win->vas_win.winid, win->pid);
> return -EIO;
> }
>
> @@ -338,6 +337,8 @@ static struct vas_window *vas_allocate_window(int vas_id,
> u64 flags,
> }
> }
>
> + txwin->pid = 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 d6ea8ab8b07a..2872532ed72a 100644
> --- a/arch/powerpc/platforms/pseries/vas.h
> +++ b/arch/powerpc/platforms/pseries/vas.h
> @@ -114,6 +114,7 @@ struct pseries_vas_window {
> u64 domain[6]; /* Associativity domain Ids */
> /* this window is allocated */
> u64 util;
> + u32 pid; /* PID associated with this window */
>
> /* List of windows opened which is used for LPM */
> struct list_head win_list;
> --
> 2.27.0
>
>
>
