From f0e2f38befa787f0267419082b33e8ac72269d77 Mon Sep 17 00:00:00 2001 From: Francisco Jerez Date: Sat, 20 Feb 2010 07:30:15 +1000 Subject: drm/ttm: fix caching problem on non-PAT systems. http://bugzilla.kernel.org/show_bug.cgi?id=15328 This fixes a serious regression on AGP/non-PAT systems, where pages were ending up in the wrong state and slowing down the whole system. [airlied: taken this from the bug as the other option is to revert the change which caused it]. Tested-by: John W. Linville (in bug). Signed-off-by: Dave Airlie --- drivers/gpu/drm/ttm/ttm_tt.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'drivers/gpu/drm/ttm') diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index e2123af7775a..3d47a2c12322 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -196,14 +196,15 @@ EXPORT_SYMBOL(ttm_tt_populate); #ifdef CONFIG_X86 static inline int ttm_tt_set_page_caching(struct page *p, - enum ttm_caching_state c_state) + enum ttm_caching_state c_old, + enum ttm_caching_state c_new) { int ret = 0; if (PageHighMem(p)) return 0; - if (get_page_memtype(p) != -1) { + if (c_old != tt_cached) { /* p isn't in the default caching state, set it to * writeback first to free its current memtype. */ @@ -212,16 +213,17 @@ static inline int ttm_tt_set_page_caching(struct page *p, return ret; } - if (c_state == tt_wc) + if (c_new == tt_wc) ret = set_memory_wc((unsigned long) page_address(p), 1); - else if (c_state == tt_uncached) + else if (c_new == tt_uncached) ret = set_pages_uc(p, 1); return ret; } #else /* CONFIG_X86 */ static inline int ttm_tt_set_page_caching(struct page *p, - enum ttm_caching_state c_state) + enum ttm_caching_state c_old, + enum ttm_caching_state c_new) { return 0; } @@ -254,7 +256,9 @@ static int ttm_tt_set_caching(struct ttm_tt *ttm, for (i = 0; i < ttm->num_pages; ++i) { cur_page = ttm->pages[i]; if (likely(cur_page != NULL)) { - ret = ttm_tt_set_page_caching(cur_page, c_state); + ret = ttm_tt_set_page_caching(cur_page, + ttm->caching_state, + c_state); if (unlikely(ret != 0)) goto out_err; } @@ -268,7 +272,7 @@ out_err: for (j = 0; j < i; ++j) { cur_page = ttm->pages[j]; if (likely(cur_page != NULL)) { - (void)ttm_tt_set_page_caching(cur_page, + (void)ttm_tt_set_page_caching(cur_page, c_state, ttm->caching_state); } } -- cgit v1.2.3