diff options
author | Rakib Mullick <rakib.mullick@gmail.com> | 2017-11-17 16:40:15 +0100 |
---|---|---|
committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2017-12-11 18:17:40 +0100 |
commit | 84b12b752f41cd3d25d75692c2145d816e42926c (patch) | |
tree | 9a0b800cf0acc3fd59f31dbc117145a10be1b371 /kernel/rcu | |
parent | rcu: Add comment giving debug strategy for double call_rcu() (diff) | |
download | linux-84b12b752f41cd3d25d75692c2145d816e42926c.tar.xz linux-84b12b752f41cd3d25d75692c2145d816e42926c.zip |
rcu: Remove have_rcu_nocb_mask from tree_plugin.h
Currently have_rcu_nocb_mask is used to avoid double allocation of
rcu_nocb_mask during boot up. Due to different representation of
cpumask_var_t on different kernel config CPUMASK=y(or n) it was okay.
But now we have a helper cpumask_available(), which can be utilized
to check whether rcu_nocb_mask has been allocated or not without using
a variable.
Removing the variable also reduces vmlinux size.
Unpatched version:
text data bss dec hex filename
13050393 7852470 14543408 35446271 21cddff vmlinux
Patched version:
text data bss dec hex filename
13050390 7852438 14543408 35446236 21cdddc vmlinux
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu')
-rw-r--r-- | kernel/rcu/tree_plugin.h | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index db85ca3975f1..13a8e08f1998 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -61,7 +61,6 @@ DEFINE_PER_CPU(char, rcu_cpu_has_work); #ifdef CONFIG_RCU_NOCB_CPU static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */ -static bool have_rcu_nocb_mask; /* Was rcu_nocb_mask allocated? */ static bool __read_mostly rcu_nocb_poll; /* Offload kthread are to poll. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ @@ -1752,7 +1751,6 @@ static void increment_cpu_stall_ticks(void) static int __init rcu_nocb_setup(char *str) { alloc_bootmem_cpumask_var(&rcu_nocb_mask); - have_rcu_nocb_mask = true; cpulist_parse(str, rcu_nocb_mask); return 1; } @@ -1801,7 +1799,7 @@ static void rcu_init_one_nocb(struct rcu_node *rnp) /* Is the specified CPU a no-CBs CPU? */ bool rcu_is_nocb_cpu(int cpu) { - if (have_rcu_nocb_mask) + if (cpumask_available(rcu_nocb_mask)) return cpumask_test_cpu(cpu, rcu_nocb_mask); return false; } @@ -2295,14 +2293,13 @@ void __init rcu_init_nohz(void) need_rcu_nocb_mask = true; #endif /* #if defined(CONFIG_NO_HZ_FULL) */ - if (!have_rcu_nocb_mask && need_rcu_nocb_mask) { + if (!cpumask_available(rcu_nocb_mask) && need_rcu_nocb_mask) { if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) { pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n"); return; } - have_rcu_nocb_mask = true; } - if (!have_rcu_nocb_mask) + if (!cpumask_available(rcu_nocb_mask)) return; #if defined(CONFIG_NO_HZ_FULL) @@ -2428,7 +2425,7 @@ static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp) struct rcu_data *rdp_leader = NULL; /* Suppress misguided gcc warn. */ struct rcu_data *rdp_prev = NULL; - if (!have_rcu_nocb_mask) + if (!cpumask_available(rcu_nocb_mask)) return; if (ls == -1) { ls = int_sqrt(nr_cpu_ids); |