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-rw-r--r--init/Kconfig94
-rw-r--r--init/main.c36
2 files changed, 112 insertions, 18 deletions
diff --git a/init/Kconfig b/init/Kconfig
index f763762d544a..13627191a60d 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -588,6 +588,13 @@ config KALLSYMS_ALL
Say N.
+config KALLSYMS_STRIP_GENERATED
+ bool "Strip machine generated symbols from kallsyms"
+ depends on KALLSYMS_ALL
+ default y
+ help
+ Say N if you want kallsyms to retain even machine generated symbols.
+
config KALLSYMS_EXTRA_PASS
bool "Do an extra kallsyms pass"
depends on KALLSYMS
@@ -808,6 +815,7 @@ config TRACEPOINTS
config MARKERS
bool "Activate markers"
+ depends on TRACEPOINTS
help
Place an empty function call at each marker site. Can be
dynamically changed for a probe function.
@@ -928,10 +936,90 @@ source "block/Kconfig"
config PREEMPT_NOTIFIERS
bool
+choice
+ prompt "RCU Implementation"
+ default CLASSIC_RCU
+
config CLASSIC_RCU
- def_bool !PREEMPT_RCU
+ bool "Classic RCU"
help
This option selects the classic RCU implementation that is
designed for best read-side performance on non-realtime
- systems. Classic RCU is the default. Note that the
- PREEMPT_RCU symbol is used to select/deselect this option.
+ systems.
+
+ Select this option if you are unsure.
+
+config TREE_RCU
+ bool "Tree-based hierarchical RCU"
+ help
+ This option selects the RCU implementation that is
+ designed for very large SMP system with hundreds or
+ thousands of CPUs.
+
+config PREEMPT_RCU
+ bool "Preemptible RCU"
+ depends on PREEMPT
+ help
+ This option reduces the latency of the kernel by making certain
+ RCU sections preemptible. Normally RCU code is non-preemptible, if
+ this option is selected then read-only RCU sections become
+ preemptible. This helps latency, but may expose bugs due to
+ now-naive assumptions about each RCU read-side critical section
+ remaining on a given CPU through its execution.
+
+endchoice
+
+config RCU_TRACE
+ bool "Enable tracing for RCU"
+ depends on TREE_RCU || PREEMPT_RCU
+ help
+ This option provides tracing in RCU which presents stats
+ in debugfs for debugging RCU implementation.
+
+ Say Y here if you want to enable RCU tracing
+ Say N if you are unsure.
+
+config RCU_FANOUT
+ int "Tree-based hierarchical RCU fanout value"
+ range 2 64 if 64BIT
+ range 2 32 if !64BIT
+ depends on TREE_RCU
+ default 64 if 64BIT
+ default 32 if !64BIT
+ help
+ This option controls the fanout of hierarchical implementations
+ of RCU, allowing RCU to work efficiently on machines with
+ large numbers of CPUs. This value must be at least the cube
+ root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
+ systems and up to 262,144 for 64-bit systems.
+
+ Select a specific number if testing RCU itself.
+ Take the default if unsure.
+
+config RCU_FANOUT_EXACT
+ bool "Disable tree-based hierarchical RCU auto-balancing"
+ depends on TREE_RCU
+ default n
+ help
+ This option forces use of the exact RCU_FANOUT value specified,
+ regardless of imbalances in the hierarchy. This is useful for
+ testing RCU itself, and might one day be useful on systems with
+ strong NUMA behavior.
+
+ Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
+
+ Say N if unsure.
+
+config TREE_RCU_TRACE
+ def_bool RCU_TRACE && TREE_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the TREE_RCU implementation,
+ permitting Makefile to trivially select kernel/rcutree_trace.c.
+
+config PREEMPT_RCU_TRACE
+ def_bool RCU_TRACE && PREEMPT_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the PREEMPT_RCU implementation,
+ permitting Makefile to trivially select kernel/rcupreempt_trace.c.
diff --git a/init/main.c b/init/main.c
index c1f999a3cf31..2a7ce0f8e453 100644
--- a/init/main.c
+++ b/init/main.c
@@ -63,6 +63,7 @@
#include <linux/signal.h>
#include <linux/idr.h>
#include <linux/ftrace.h>
+#include <trace/boot.h>
#include <asm/io.h>
#include <asm/bugs.h>
@@ -680,6 +681,7 @@ asmlinkage void __init start_kernel(void)
efi_enter_virtual_mode();
#endif
thread_info_cache_init();
+ cred_init();
fork_init(num_physpages);
proc_caches_init();
buffer_init();
@@ -714,31 +716,35 @@ core_param(initcall_debug, initcall_debug, bool, 0644);
int do_one_initcall(initcall_t fn)
{
int count = preempt_count();
- ktime_t delta;
+ ktime_t calltime, delta, rettime;
char msgbuf[64];
- struct boot_trace it;
+ struct boot_trace_call call;
+ struct boot_trace_ret ret;
if (initcall_debug) {
- it.caller = task_pid_nr(current);
- printk("calling %pF @ %i\n", fn, it.caller);
- it.calltime = ktime_get();
+ call.caller = task_pid_nr(current);
+ printk("calling %pF @ %i\n", fn, call.caller);
+ calltime = ktime_get();
+ trace_boot_call(&call, fn);
+ enable_boot_trace();
}
- it.result = fn();
+ ret.result = fn();
if (initcall_debug) {
- it.rettime = ktime_get();
- delta = ktime_sub(it.rettime, it.calltime);
- it.duration = (unsigned long long) delta.tv64 >> 10;
+ disable_boot_trace();
+ rettime = ktime_get();
+ delta = ktime_sub(rettime, calltime);
+ ret.duration = (unsigned long long) ktime_to_ns(delta) >> 10;
+ trace_boot_ret(&ret, fn);
printk("initcall %pF returned %d after %Ld usecs\n", fn,
- it.result, it.duration);
- trace_boot(&it, fn);
+ ret.result, ret.duration);
}
msgbuf[0] = 0;
- if (it.result && it.result != -ENODEV && initcall_debug)
- sprintf(msgbuf, "error code %d ", it.result);
+ if (ret.result && ret.result != -ENODEV && initcall_debug)
+ sprintf(msgbuf, "error code %d ", ret.result);
if (preempt_count() != count) {
strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
@@ -752,7 +758,7 @@ int do_one_initcall(initcall_t fn)
printk("initcall %pF returned with %s\n", fn, msgbuf);
}
- return it.result;
+ return ret.result;
}
@@ -893,7 +899,7 @@ static int __init kernel_init(void * unused)
* we're essentially up and running. Get rid of the
* initmem segments and start the user-mode stuff..
*/
- stop_boot_trace();
+
init_post();
return 0;
}