diff options
Diffstat (limited to 'meta/recipes-kernel/lttng/lttng-modules/0008-fix-writeback-Fix-sync-livelock-due-to-b_dirty_time-.patch')
| -rw-r--r-- | meta/recipes-kernel/lttng/lttng-modules/0008-fix-writeback-Fix-sync-livelock-due-to-b_dirty_time-.patch | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/meta/recipes-kernel/lttng/lttng-modules/0008-fix-writeback-Fix-sync-livelock-due-to-b_dirty_time-.patch b/meta/recipes-kernel/lttng/lttng-modules/0008-fix-writeback-Fix-sync-livelock-due-to-b_dirty_time-.patch new file mode 100644 index 0000000000..7a0d9a38b8 --- /dev/null +++ b/meta/recipes-kernel/lttng/lttng-modules/0008-fix-writeback-Fix-sync-livelock-due-to-b_dirty_time-.patch @@ -0,0 +1,117 @@ +From 87b2affc3eb06f3fb2d0923f18af37713eb6814b Mon Sep 17 00:00:00 2001 +From: Michael Jeanson <mjeanson@efficios.com> +Date: Mon, 31 Aug 2020 14:16:01 -0400 +Subject: [PATCH 08/10] fix: writeback: Fix sync livelock due to b_dirty_time + processing (v5.9) + +See upstream commit: + + commit f9cae926f35e8230330f28c7b743ad088611a8de + Author: Jan Kara <jack@suse.cz> + Date: Fri May 29 16:08:58 2020 +0200 + + writeback: Fix sync livelock due to b_dirty_time processing + + When we are processing writeback for sync(2), move_expired_inodes() + didn't set any inode expiry value (older_than_this). This can result in + writeback never completing if there's steady stream of inodes added to + b_dirty_time list as writeback rechecks dirty lists after each writeback + round whether there's more work to be done. Fix the problem by using + sync(2) start time is inode expiry value when processing b_dirty_time + list similarly as for ordinarily dirtied inodes. This requires some + refactoring of older_than_this handling which simplifies the code + noticeably as a bonus. + +Upstream-Status: Backport + +Change-Id: I8b894b13ccc14d9b8983ee4c2810a927c319560b +Signed-off-by: Michael Jeanson <mjeanson@efficios.com> +Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> +--- + .../events/lttng-module/writeback.h | 39 ++++++++++++------- + 1 file changed, 26 insertions(+), 13 deletions(-) + +diff --git a/instrumentation/events/lttng-module/writeback.h b/instrumentation/events/lttng-module/writeback.h +index ece67ad..e9018dd 100644 +--- a/instrumentation/events/lttng-module/writeback.h ++++ b/instrumentation/events/lttng-module/writeback.h +@@ -384,34 +384,48 @@ LTTNG_TRACEPOINT_EVENT_WBC_INSTANCE(wbc_balance_dirty_wait, writeback_wbc_balanc + #endif + LTTNG_TRACEPOINT_EVENT_WBC_INSTANCE(wbc_writepage, writeback_wbc_writepage) + +-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)) ++#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,9,0)) ++LTTNG_TRACEPOINT_EVENT(writeback_queue_io, ++ TP_PROTO(struct bdi_writeback *wb, ++ struct wb_writeback_work *work, ++ unsigned long dirtied_before, ++ int moved), ++ TP_ARGS(wb, work, dirtied_before, moved), ++ TP_FIELDS( ++ ctf_array_text(char, name, dev_name(wb->bdi->dev), 32) ++ ctf_integer(unsigned long, older, dirtied_before) ++ ctf_integer(int, moved, moved) ++ ) ++) ++#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) + LTTNG_TRACEPOINT_EVENT(writeback_queue_io, + TP_PROTO(struct bdi_writeback *wb, +-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) + struct wb_writeback_work *work, +-#else +- unsigned long *older_than_this, +-#endif + int moved), +-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) + TP_ARGS(wb, work, moved), +-#else ++ TP_FIELDS( ++ ctf_array_text(char, name, dev_name(wb->bdi->dev), 32) ++ ctf_integer(int, moved, moved) ++ ) ++) ++#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)) ++LTTNG_TRACEPOINT_EVENT(writeback_queue_io, ++ TP_PROTO(struct bdi_writeback *wb, ++ unsigned long *older_than_this, ++ int moved), + TP_ARGS(wb, older_than_this, moved), +-#endif + TP_FIELDS( + ctf_array_text(char, name, dev_name(wb->bdi->dev), 32) +-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) +-#else + ctf_integer(unsigned long, older, + older_than_this ? *older_than_this : 0) + ctf_integer(long, age, + older_than_this ? + (jiffies - *older_than_this) * 1000 / HZ + : -1) +-#endif + ctf_integer(int, moved, moved) + ) + ) ++#endif + + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,8,0)) + LTTNG_TRACEPOINT_EVENT_MAP(global_dirty_state, +@@ -460,7 +474,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(global_dirty_state, + ctf_integer(unsigned long, dirty_limit, global_dirty_limit) + ) + ) +-#else ++#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)) + LTTNG_TRACEPOINT_EVENT_MAP(global_dirty_state, + + writeback_global_dirty_state, +@@ -485,7 +499,6 @@ LTTNG_TRACEPOINT_EVENT_MAP(global_dirty_state, + ) + ) + #endif +-#endif + + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) + +-- +2.19.1 + |