From dfe954e4456277effffb2c5add47fa25390f8cea Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Tue, 7 Nov 2017 18:23:46 -0800 Subject: [PATCH] powerpc/vas: Reduce polling interval for busy state A VAS window is normally in "busy" state for only a short duration. Reduce the time we wait for the window to go to "not-busy" state to speed-up vas_win_close() a bit. Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/powernv/vas-window.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index 95622a9..1422cdd 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -1060,21 +1060,23 @@ int vas_paste_crb(struct vas_window *txwin, int offset, bool re) } EXPORT_SYMBOL_GPL(vas_paste_crb); +/* + * Wait for the window to go to "not-busy" state. It should only take a + * short time to queue a CRB, so window should not be busy for too long. + * Trying 5ms intervals. + */ static void poll_window_busy_state(struct vas_window *window) { int busy; u64 val; retry: - /* - * Poll Window Busy flag - */ val = read_hvwc_reg(window, VREG(WIN_STATUS)); busy = GET_FIELD(VAS_WIN_BUSY, val); if (busy) { val = 0; set_current_state(TASK_UNINTERRUPTIBLE); - schedule_timeout(HZ); + schedule_timeout(msecs_to_jiffies(5)); goto retry; } } -- 2.7.4