* [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces @ 2020-02-07 15:17 Chris Wilson 2020-02-07 19:04 ` [Intel-gfx] ✓ Fi.CI.BAT: success for " Patchwork ` (2 more replies) 0 siblings, 3 replies; 5+ messages in thread From: Chris Wilson @ 2020-02-07 15:17 UTC (permalink / raw) To: intel-gfx; +Cc: dri-devel We try hard to select a suitable hole in the drm_mm first time. But if that is unsuccessful, we then have to look at neighbouring nodes, and this requires traversing the rbtree. Walking the rbtree can be slow (much slower than a linear list for deep trees), and if the drm_mm has been purposefully fragmented our search can be trapped for a long, long time. For non-preemptible kernels, we need to break up long CPU bound sections by manually checking for cond_resched(); similarly we should also bail out if we have been told to terminate. (In an ideal world, we would break for any signal, but we need to trade off having to perform the search again after ERESTARTSYS, which again may form a trap of making no forward progress.) Reported-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> --- drivers/gpu/drm/drm_mm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 2a6e34663146..47d5de9ca0a8 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -45,6 +45,7 @@ #include <linux/export.h> #include <linux/interval_tree_generic.h> #include <linux/seq_file.h> +#include <linux/sched/signal.h> #include <linux/slab.h> #include <linux/stacktrace.h> @@ -366,6 +367,11 @@ next_hole(struct drm_mm *mm, struct drm_mm_node *node, enum drm_mm_insert_mode mode) { + /* Searching is slow; check if we ran out of time/patience */ + cond_resched(); + if (fatal_signal_pending(current)) + return NULL; + switch (mode) { default: case DRM_MM_INSERT_BEST: @@ -557,7 +563,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, return 0; } - return -ENOSPC; + return signal_pending(current) ? -ERESTARTSYS : -ENOSPC; } EXPORT_SYMBOL(drm_mm_insert_node_in_range); -- 2.25.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [Intel-gfx] ✓ Fi.CI.BAT: success for drm/mm: Break long searches in fragmented address spaces 2020-02-07 15:17 [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces Chris Wilson @ 2020-02-07 19:04 ` Patchwork 2020-02-11 8:54 ` [Intel-gfx] ✓ Fi.CI.IGT: " Patchwork 2020-02-11 22:56 ` [Intel-gfx] [PATCH] " Andi Shyti 2 siblings, 0 replies; 5+ messages in thread From: Patchwork @ 2020-02-07 19:04 UTC (permalink / raw) To: Chris Wilson; +Cc: intel-gfx == Series Details == Series: drm/mm: Break long searches in fragmented address spaces URL : https://patchwork.freedesktop.org/series/73154/ State : success == Summary == CI Bug Log - changes from CI_DRM_7887 -> Patchwork_16484 ==================================================== Summary ------- **SUCCESS** No regressions found. External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/index.html Known issues ------------ Here are the changes found in Patchwork_16484 that come from known issues: ### IGT changes ### #### Issues hit #### * igt@gem_close_race@basic-threads: - fi-byt-n2820: [PASS][1] -> [INCOMPLETE][2] ([i915#45]) [1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-byt-n2820/igt@gem_close_race@basic-threads.html [2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-byt-n2820/igt@gem_close_race@basic-threads.html * igt@i915_selftest@live_blt: - fi-bsw-n3050: [PASS][3] -> [INCOMPLETE][4] ([i915#392]) [3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-bsw-n3050/igt@i915_selftest@live_blt.html [4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-bsw-n3050/igt@i915_selftest@live_blt.html #### Possible fixes #### * igt@i915_selftest@live_execlists: - fi-icl-y: [DMESG-FAIL][5] ([fdo#108569]) -> [PASS][6] [5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-icl-y/igt@i915_selftest@live_execlists.html [6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-icl-y/igt@i915_selftest@live_execlists.html * igt@i915_selftest@live_gem_contexts: - fi-cfl-8700k: [DMESG-FAIL][7] ([i915#623]) -> [PASS][8] [7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-cfl-8700k/igt@i915_selftest@live_gem_contexts.html [8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-cfl-8700k/igt@i915_selftest@live_gem_contexts.html * igt@i915_selftest@live_gtt: - fi-icl-guc: [TIMEOUT][9] ([fdo#112271]) -> [PASS][10] [9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-icl-guc/igt@i915_selftest@live_gtt.html [10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-icl-guc/igt@i915_selftest@live_gtt.html * igt@kms_chamelium@hdmi-hpd-fast: - fi-kbl-7500u: [FAIL][11] ([fdo#111096] / [i915#323]) -> [PASS][12] [11]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/fi-kbl-7500u/igt@kms_chamelium@hdmi-hpd-fast.html [12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/fi-kbl-7500u/igt@kms_chamelium@hdmi-hpd-fast.html [fdo#108569]: https://bugs.freedesktop.org/show_bug.cgi?id=108569 [fdo#111096]: https://bugs.freedesktop.org/show_bug.cgi?id=111096 [fdo#112271]: https://bugs.freedesktop.org/show_bug.cgi?id=112271 [i915#323]: https://gitlab.freedesktop.org/drm/intel/issues/323 [i915#392]: https://gitlab.freedesktop.org/drm/intel/issues/392 [i915#45]: https://gitlab.freedesktop.org/drm/intel/issues/45 [i915#623]: https://gitlab.freedesktop.org/drm/intel/issues/623 Participating hosts (48 -> 42) ------------------------------ Additional (3): fi-skl-lmem fi-blb-e6850 fi-bdw-5557u Missing (9): fi-hsw-4200u fi-skl-6770hq fi-bsw-cyan fi-bwr-2160 fi-ctg-p8600 fi-ivb-3770 fi-byt-clapper fi-bdw-samus fi-snb-2600 Build changes ------------- * CI: CI-20190529 -> None * Linux: CI_DRM_7887 -> Patchwork_16484 CI-20190529: 20190529 CI_DRM_7887: b147ed9753265260d6380604de01c3d646a323cd @ git://anongit.freedesktop.org/gfx-ci/linux IGT_5425: ad4542ef1adbaa1227bc9ba9e24bb0e0f6dd408d @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools Patchwork_16484: 0aacd903a4e7a4a30b32b1b91de5ae4a4dea7102 @ git://anongit.freedesktop.org/gfx-ci/linux == Linux commits == 0aacd903a4e7 drm/mm: Break long searches in fragmented address spaces == Logs == For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/index.html _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Intel-gfx] ✓ Fi.CI.IGT: success for drm/mm: Break long searches in fragmented address spaces 2020-02-07 15:17 [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces Chris Wilson 2020-02-07 19:04 ` [Intel-gfx] ✓ Fi.CI.BAT: success for " Patchwork @ 2020-02-11 8:54 ` Patchwork 2020-02-11 22:56 ` [Intel-gfx] [PATCH] " Andi Shyti 2 siblings, 0 replies; 5+ messages in thread From: Patchwork @ 2020-02-11 8:54 UTC (permalink / raw) To: Chris Wilson; +Cc: intel-gfx == Series Details == Series: drm/mm: Break long searches in fragmented address spaces URL : https://patchwork.freedesktop.org/series/73154/ State : success == Summary == CI Bug Log - changes from CI_DRM_7887_full -> Patchwork_16484_full ==================================================== Summary ------- **SUCCESS** No regressions found. Known issues ------------ Here are the changes found in Patchwork_16484_full that come from known issues: ### IGT changes ### #### Issues hit #### * igt@gem_exec_schedule@in-order-bsd: - shard-iclb: [PASS][1] -> [SKIP][2] ([fdo#112146]) +7 similar issues [1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb5/igt@gem_exec_schedule@in-order-bsd.html [2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb1/igt@gem_exec_schedule@in-order-bsd.html * igt@gem_exec_schedule@pi-shared-iova-bsd: - shard-iclb: [PASS][3] -> [SKIP][4] ([i915#677]) +1 similar issue [3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb8/igt@gem_exec_schedule@pi-shared-iova-bsd.html [4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb1/igt@gem_exec_schedule@pi-shared-iova-bsd.html * igt@gem_ppgtt@flink-and-close-vma-leak: - shard-apl: [PASS][5] -> [FAIL][6] ([i915#644]) [5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-apl1/igt@gem_ppgtt@flink-and-close-vma-leak.html [6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-apl4/igt@gem_ppgtt@flink-and-close-vma-leak.html * igt@kms_flip@flip-vs-expired-vblank: - shard-glk: [PASS][7] -> [FAIL][8] ([i915#79]) [7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-glk6/igt@kms_flip@flip-vs-expired-vblank.html [8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-glk8/igt@kms_flip@flip-vs-expired-vblank.html * igt@kms_flip@modeset-vs-vblank-race-interruptible: - shard-glk: [PASS][9] -> [FAIL][10] ([i915#407]) [9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-glk9/igt@kms_flip@modeset-vs-vblank-race-interruptible.html [10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-glk3/igt@kms_flip@modeset-vs-vblank-race-interruptible.html * igt@kms_plane@plane-panning-bottom-right-suspend-pipe-c-planes: - shard-apl: [PASS][11] -> [DMESG-WARN][12] ([i915#180]) [11]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-apl6/igt@kms_plane@plane-panning-bottom-right-suspend-pipe-c-planes.html [12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-apl4/igt@kms_plane@plane-panning-bottom-right-suspend-pipe-c-planes.html * igt@kms_psr@psr2_cursor_plane_onoff: - shard-iclb: [PASS][13] -> [SKIP][14] ([fdo#109441]) +2 similar issues [13]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb2/igt@kms_psr@psr2_cursor_plane_onoff.html [14]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb8/igt@kms_psr@psr2_cursor_plane_onoff.html * igt@kms_setmode@basic: - shard-apl: [PASS][15] -> [FAIL][16] ([i915#31]) [15]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-apl6/igt@kms_setmode@basic.html [16]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-apl4/igt@kms_setmode@basic.html - shard-glk: [PASS][17] -> [FAIL][18] ([i915#31]) [17]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-glk2/igt@kms_setmode@basic.html [18]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-glk1/igt@kms_setmode@basic.html * igt@perf_pmu@busy-no-semaphores-vcs1: - shard-iclb: [PASS][19] -> [SKIP][20] ([fdo#112080]) +13 similar issues [19]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb1/igt@perf_pmu@busy-no-semaphores-vcs1.html [20]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb6/igt@perf_pmu@busy-no-semaphores-vcs1.html * igt@prime_busy@hang-bsd2: - shard-iclb: [PASS][21] -> [SKIP][22] ([fdo#109276]) +11 similar issues [21]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb4/igt@prime_busy@hang-bsd2.html [22]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb6/igt@prime_busy@hang-bsd2.html #### Possible fixes #### * igt@gem_exec_balancer@hang: - shard-iclb: [TIMEOUT][23] ([fdo#112271]) -> [PASS][24] [23]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb4/igt@gem_exec_balancer@hang.html [24]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb5/igt@gem_exec_balancer@hang.html * igt@gem_exec_balancer@smoke: - shard-iclb: [SKIP][25] ([fdo#110854]) -> [PASS][26] [25]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb5/igt@gem_exec_balancer@smoke.html [26]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb1/igt@gem_exec_balancer@smoke.html * igt@gem_exec_parallel@vcs1-fds: - shard-iclb: [SKIP][27] ([fdo#112080]) -> [PASS][28] +8 similar issues [27]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb6/igt@gem_exec_parallel@vcs1-fds.html [28]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb2/igt@gem_exec_parallel@vcs1-fds.html * igt@gem_exec_schedule@preempt-self-bsd: - shard-iclb: [SKIP][29] ([fdo#112146]) -> [PASS][30] +5 similar issues [29]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb1/igt@gem_exec_schedule@preempt-self-bsd.html [30]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb6/igt@gem_exec_schedule@preempt-self-bsd.html * igt@gem_ppgtt@flink-and-close-vma-leak: - shard-glk: [FAIL][31] ([i915#644]) -> [PASS][32] [31]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-glk4/igt@gem_ppgtt@flink-and-close-vma-leak.html [32]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-glk2/igt@gem_ppgtt@flink-and-close-vma-leak.html * igt@i915_pm_dc@dc6-psr: - shard-iclb: [FAIL][33] ([i915#454]) -> [PASS][34] [33]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb2/igt@i915_pm_dc@dc6-psr.html [34]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb4/igt@i915_pm_dc@dc6-psr.html * igt@i915_pm_rps@waitboost: - shard-iclb: [FAIL][35] ([i915#413]) -> [PASS][36] [35]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb7/igt@i915_pm_rps@waitboost.html [36]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb7/igt@i915_pm_rps@waitboost.html * igt@kms_plane_lowres@pipe-a-tiling-x: - shard-glk: [FAIL][37] ([i915#899]) -> [PASS][38] +1 similar issue [37]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-glk3/igt@kms_plane_lowres@pipe-a-tiling-x.html [38]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-glk7/igt@kms_plane_lowres@pipe-a-tiling-x.html * igt@kms_psr@psr2_cursor_plane_move: - shard-iclb: [SKIP][39] ([fdo#109441]) -> [PASS][40] +1 similar issue [39]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb6/igt@kms_psr@psr2_cursor_plane_move.html [40]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb2/igt@kms_psr@psr2_cursor_plane_move.html * igt@prime_vgem@fence-wait-bsd2: - shard-iclb: [SKIP][41] ([fdo#109276]) -> [PASS][42] +26 similar issues [41]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb6/igt@prime_vgem@fence-wait-bsd2.html [42]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb2/igt@prime_vgem@fence-wait-bsd2.html #### Warnings #### * igt@i915_pm_rpm@legacy-planes: - shard-snb: [INCOMPLETE][43] ([i915#82]) -> [SKIP][44] ([fdo#109271]) [43]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-snb4/igt@i915_pm_rpm@legacy-planes.html [44]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-snb6/igt@i915_pm_rpm@legacy-planes.html * igt@kms_dp_dsc@basic-dsc-enable-edp: - shard-iclb: [DMESG-WARN][45] ([fdo#107724]) -> [SKIP][46] ([fdo#109349]) [45]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7887/shard-iclb2/igt@kms_dp_dsc@basic-dsc-enable-edp.html [46]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/shard-iclb8/igt@kms_dp_dsc@basic-dsc-enable-edp.html {name}: This element is suppressed. This means it is ignored when computing the status of the difference (SUCCESS, WARNING, or FAILURE). [fdo#103927]: https://bugs.freedesktop.org/show_bug.cgi?id=103927 [fdo#107724]: https://bugs.freedesktop.org/show_bug.cgi?id=107724 [fdo#109271]: https://bugs.freedesktop.org/show_bug.cgi?id=109271 [fdo#109276]: https://bugs.freedesktop.org/show_bug.cgi?id=109276 [fdo#109349]: https://bugs.freedesktop.org/show_bug.cgi?id=109349 [fdo#109441]: https://bugs.freedesktop.org/show_bug.cgi?id=109441 [fdo#110854]: https://bugs.freedesktop.org/show_bug.cgi?id=110854 [fdo#112080]: https://bugs.freedesktop.org/show_bug.cgi?id=112080 [fdo#112146]: https://bugs.freedesktop.org/show_bug.cgi?id=112146 [fdo#112271]: https://bugs.freedesktop.org/show_bug.cgi?id=112271 [i915#180]: https://gitlab.freedesktop.org/drm/intel/issues/180 [i915#31]: https://gitlab.freedesktop.org/drm/intel/issues/31 [i915#407]: https://gitlab.freedesktop.org/drm/intel/issues/407 [i915#413]: https://gitlab.freedesktop.org/drm/intel/issues/413 [i915#454]: https://gitlab.freedesktop.org/drm/intel/issues/454 [i915#644]: https://gitlab.freedesktop.org/drm/intel/issues/644 [i915#677]: https://gitlab.freedesktop.org/drm/intel/issues/677 [i915#679]: https://gitlab.freedesktop.org/drm/intel/issues/679 [i915#79]: https://gitlab.freedesktop.org/drm/intel/issues/79 [i915#82]: https://gitlab.freedesktop.org/drm/intel/issues/82 [i915#899]: https://gitlab.freedesktop.org/drm/intel/issues/899 Participating hosts (10 -> 10) ------------------------------ No changes in participating hosts Build changes ------------- * CI: CI-20190529 -> None * Linux: CI_DRM_7887 -> Patchwork_16484 CI-20190529: 20190529 CI_DRM_7887: b147ed9753265260d6380604de01c3d646a323cd @ git://anongit.freedesktop.org/gfx-ci/linux IGT_5425: ad4542ef1adbaa1227bc9ba9e24bb0e0f6dd408d @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools Patchwork_16484: 0aacd903a4e7a4a30b32b1b91de5ae4a4dea7102 @ git://anongit.freedesktop.org/gfx-ci/linux piglit_4509: fdc5a4ca11124ab8413c7988896eec4c97336694 @ git://anongit.freedesktop.org/piglit == Logs == For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_16484/index.html _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces 2020-02-07 15:17 [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces Chris Wilson 2020-02-07 19:04 ` [Intel-gfx] ✓ Fi.CI.BAT: success for " Patchwork 2020-02-11 8:54 ` [Intel-gfx] ✓ Fi.CI.IGT: " Patchwork @ 2020-02-11 22:56 ` Andi Shyti 2020-02-14 0:34 ` Chris Wilson 2 siblings, 1 reply; 5+ messages in thread From: Andi Shyti @ 2020-02-11 22:56 UTC (permalink / raw) To: Chris Wilson; +Cc: intel-gfx, dri-devel Hi Chris, On Fri, Feb 07, 2020 at 03:17:20PM +0000, Chris Wilson wrote: > We try hard to select a suitable hole in the drm_mm first time. But if > that is unsuccessful, we then have to look at neighbouring nodes, and > this requires traversing the rbtree. Walking the rbtree can be slow > (much slower than a linear list for deep trees), and if the drm_mm has > been purposefully fragmented our search can be trapped for a long, long > time. For non-preemptible kernels, we need to break up long CPU bound > sections by manually checking for cond_resched(); similarly we should checking for "fatal signals" you mean? > also bail out if we have been told to terminate. (In an ideal world, we > would break for any signal, but we need to trade off having to perform > the search again after ERESTARTSYS, which again may form a trap of > making no forward progress.) > > Reported-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> nice! Reviewed-by: Andi Shyti <andi.shyti@intel.com> Thanks, Andi > --- > drivers/gpu/drm/drm_mm.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c > index 2a6e34663146..47d5de9ca0a8 100644 > --- a/drivers/gpu/drm/drm_mm.c > +++ b/drivers/gpu/drm/drm_mm.c > @@ -45,6 +45,7 @@ > #include <linux/export.h> > #include <linux/interval_tree_generic.h> > #include <linux/seq_file.h> > +#include <linux/sched/signal.h> > #include <linux/slab.h> > #include <linux/stacktrace.h> > > @@ -366,6 +367,11 @@ next_hole(struct drm_mm *mm, > struct drm_mm_node *node, > enum drm_mm_insert_mode mode) > { > + /* Searching is slow; check if we ran out of time/patience */ > + cond_resched(); > + if (fatal_signal_pending(current)) > + return NULL; > + > switch (mode) { > default: > case DRM_MM_INSERT_BEST: > @@ -557,7 +563,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, > return 0; > } > > - return -ENOSPC; > + return signal_pending(current) ? -ERESTARTSYS : -ENOSPC; > } > EXPORT_SYMBOL(drm_mm_insert_node_in_range); > > -- > 2.25.0 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces 2020-02-11 22:56 ` [Intel-gfx] [PATCH] " Andi Shyti @ 2020-02-14 0:34 ` Chris Wilson 0 siblings, 0 replies; 5+ messages in thread From: Chris Wilson @ 2020-02-14 0:34 UTC (permalink / raw) To: Andi Shyti; +Cc: intel-gfx, dri-devel Quoting Andi Shyti (2020-02-11 22:56:44) > Hi Chris, > > On Fri, Feb 07, 2020 at 03:17:20PM +0000, Chris Wilson wrote: > > We try hard to select a suitable hole in the drm_mm first time. But if > > that is unsuccessful, we then have to look at neighbouring nodes, and > > this requires traversing the rbtree. Walking the rbtree can be slow > > (much slower than a linear list for deep trees), and if the drm_mm has > > been purposefully fragmented our search can be trapped for a long, long > > time. For non-preemptible kernels, we need to break up long CPU bound > > sections by manually checking for cond_resched(); similarly we should > > checking for "fatal signals" you mean? We need to call schedule() ourselves for non-voluntary CONFIG_PREEMPT kernels, and we need to escape from the kernel back to userspace to handle a pending signal in this process. Other applications, sysadmins tend to notice and complain about driver hogging a CPU not letting anything else run; typically the user notices that their application doesn't close on ^C. (That is schedule() delays of a few ms will be noticed, but it takes a couple of seconds before a user will become aware of a severe problem with a stuck signal. :) Now since responding to a signal itself may be expensive (we have to restart the syscall and re-process all the state from before this point), we make the trade-off here of only responding to a fatal-signal (process exit), which should allow for faster system recovery under pathological conditions. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2020-02-14 0:35 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-02-07 15:17 [Intel-gfx] [PATCH] drm/mm: Break long searches in fragmented address spaces Chris Wilson 2020-02-07 19:04 ` [Intel-gfx] ✓ Fi.CI.BAT: success for " Patchwork 2020-02-11 8:54 ` [Intel-gfx] ✓ Fi.CI.IGT: " Patchwork 2020-02-11 22:56 ` [Intel-gfx] [PATCH] " Andi Shyti 2020-02-14 0:34 ` Chris Wilson
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