From 7a787c25b8df1776be164fb7c9d27d1ec50272d6 Mon Sep 17 00:00:00 2001 From: Hongchao Zhang Date: Wed, 2 May 2018 14:21:47 -0400 Subject: [PATCH] staging: lustre: obdclass: guarantee all keys filled In keys_fill, the key_set_version could be changed after the keys are filled, then the keys in this context won't be refilled by the following lu_context_refill for its version is equal to the current key_set_version. In lu_context_refill, the key_set_version should be protected before comparing it to version stored in the lu_context. Signed-off-by: Hongchao Zhang Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8346 Reviewed-on: https://review.whamcloud.com/26099 Reviewed-on: https://review.whamcloud.com/27448 Reviewed-on: https://review.whamcloud.com/27994 Reviewed-by: Patrick Farrell Reviewed-by: Jinshan Xiong Reviewed-by: Mike Pershin Reviewed-by: Fan Yong Reviewed-by: Oleg Drokin Signed-off-by: James Simmons Signed-off-by: Greg Kroah-Hartman --- drivers/staging/lustre/lustre/obdclass/lu_object.c | 29 +++++++++++++++++++--- 1 file changed, 25 insertions(+), 4 deletions(-) diff --git a/drivers/staging/lustre/lustre/obdclass/lu_object.c b/drivers/staging/lustre/lustre/obdclass/lu_object.c index 96f21a5..be10104 100644 --- a/drivers/staging/lustre/lustre/obdclass/lu_object.c +++ b/drivers/staging/lustre/lustre/obdclass/lu_object.c @@ -1396,8 +1396,8 @@ void lu_context_key_degister(struct lu_context_key *key) lu_context_key_quiesce(key); - ++key_set_version; write_lock(&lu_keys_guard); + ++key_set_version; key_fini(&lu_shrink_env.le_ctx, key->lct_index); /** @@ -1556,15 +1556,18 @@ void lu_context_key_quiesce(struct lu_context_key *key) list_for_each_entry(ctx, &lu_context_remembered, lc_remember) key_fini(ctx, key->lct_index); - write_unlock(&lu_keys_guard); + ++key_set_version; + write_unlock(&lu_keys_guard); } } void lu_context_key_revive(struct lu_context_key *key) { + write_lock(&lu_keys_guard); key->lct_tags &= ~LCT_QUIESCENT; ++key_set_version; + write_unlock(&lu_keys_guard); } static void keys_fini(struct lu_context *ctx) @@ -1583,6 +1586,7 @@ static void keys_fini(struct lu_context *ctx) static int keys_fill(struct lu_context *ctx) { + unsigned int pre_version; unsigned int i; /* @@ -1596,8 +1600,10 @@ static int keys_fill(struct lu_context *ctx) */ read_lock(&lu_keys_guard); atomic_inc(&lu_key_initing_cnt); + pre_version = key_set_version; read_unlock(&lu_keys_guard); +refill: LINVRNT(ctx->lc_value); for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { struct lu_context_key *key; @@ -1638,9 +1644,17 @@ static int keys_fill(struct lu_context *ctx) if (key->lct_exit) ctx->lc_tags |= LCT_HAS_EXIT; } - ctx->lc_version = key_set_version; } + + read_lock(&lu_keys_guard); + if (pre_version != key_set_version) { + pre_version = key_set_version; + read_unlock(&lu_keys_guard); + goto refill; + } + ctx->lc_version = key_set_version; atomic_dec(&lu_key_initing_cnt); + read_unlock(&lu_keys_guard); return 0; } @@ -1749,7 +1763,14 @@ EXPORT_SYMBOL(lu_context_exit); */ int lu_context_refill(struct lu_context *ctx) { - return likely(ctx->lc_version == key_set_version) ? 0 : keys_fill(ctx); + read_lock(&lu_keys_guard); + if (likely(ctx->lc_version == key_set_version)) { + read_unlock(&lu_keys_guard); + return 0; + } + + read_unlock(&lu_keys_guard); + return keys_fill(ctx); } /** -- 2.7.4