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[35.245.46.29]) by smtp.gmail.com with ESMTPSA id h124-20020a376c82000000b0069fc13ce203sm2270334qkc.52.2022.05.11.20.05.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 May 2022 20:05:03 -0700 (PDT) From: "Joel Fernandes (Google)" To: rcu@vger.kernel.org Cc: rushikesh.s.kadam@intel.com, urezki@gmail.com, neeraj.iitr10@gmail.com, frederic@kernel.org, paulmck@kernel.org, rostedt@goodmis.org, "Joel Fernandes (Google)" Subject: [RFC v1 05/14] fs: Move call_rcu() to call_rcu_lazy() in some paths Date: Thu, 12 May 2022 03:04:33 +0000 Message-Id: <20220512030442.2530552-6-joel@joelfernandes.org> X-Mailer: git-send-email 2.36.0.550.gb090851708-goog In-Reply-To: <20220512030442.2530552-1-joel@joelfernandes.org> References: <20220512030442.2530552-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org This is required to prevent callbacks triggering RCU machinery too quickly and too often, which adds more power to the system. When testing, we found that these paths were invoked often when the system is not doing anything (screen is ON but otherwise idle). Signed-off-by: Joel Fernandes (Google) --- fs/dcache.c | 4 ++-- fs/eventpoll.c | 2 +- fs/file_table.c | 3 ++- fs/inode.c | 2 +- 4 files changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index c84269c6e8bf..517e02cde103 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -366,7 +366,7 @@ static void dentry_free(struct dentry *dentry) if (unlikely(dname_external(dentry))) { struct external_name *p = external_name(dentry); if (likely(atomic_dec_and_test(&p->u.count))) { - call_rcu(&dentry->d_u.d_rcu, __d_free_external); + call_rcu_lazy(&dentry->d_u.d_rcu, __d_free_external); return; } } @@ -374,7 +374,7 @@ static void dentry_free(struct dentry *dentry) if (dentry->d_flags & DCACHE_NORCU) __d_free(&dentry->d_u.d_rcu); else - call_rcu(&dentry->d_u.d_rcu, __d_free); + call_rcu_lazy(&dentry->d_u.d_rcu, __d_free); } /* diff --git a/fs/eventpoll.c b/fs/eventpoll.c index e2daa940ebce..10a24cca2cff 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -728,7 +728,7 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi) * ep->mtx. The rcu read side, reverse_path_check_proc(), does not make * use of the rbn field. */ - call_rcu(&epi->rcu, epi_rcu_free); + call_rcu_lazy(&epi->rcu, epi_rcu_free); percpu_counter_dec(&ep->user->epoll_watches); diff --git a/fs/file_table.c b/fs/file_table.c index 7d2e692b66a9..415815d3ef80 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -56,7 +56,8 @@ static inline void file_free(struct file *f) security_file_free(f); if (!(f->f_mode & FMODE_NOACCOUNT)) percpu_counter_dec(&nr_files); - call_rcu(&f->f_u.fu_rcuhead, file_free_rcu); + + call_rcu_lazy(&f->f_u.fu_rcuhead, file_free_rcu); } /* diff --git a/fs/inode.c b/fs/inode.c index 63324df6fa27..b288a5bef4c7 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -312,7 +312,7 @@ static void destroy_inode(struct inode *inode) return; } inode->free_inode = ops->free_inode; - call_rcu(&inode->i_rcu, i_callback); + call_rcu_lazy(&inode->i_rcu, i_callback); } /**