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authorMarcelo Tosatti <mtosatti@redhat.com>2013-03-21 11:11:52 -0300
committerMarcelo Tosatti <mtosatti@redhat.com>2013-03-21 11:11:52 -0300
commit2ae33b389601b86a3d0cfe2d09f5e3189d5322fd (patch)
tree53e658f7ef511b5afb7d2e88753e1aaaed3de5ba /kernel/trace/trace.c
parent04b66839d312d3bdaff77f265eb7305347fa1fb7 (diff)
parent2ffdd7e23cde5a8b94d41ec0adfdd58cffe67f3a (diff)
Merge remote-tracking branch 'upstream/master' into queue
Merge reason: From: Alexander Graf <agraf@suse.de> "Just recently this really important patch got pulled into Linus' tree for 3.9: commit 1674400aaee5b466c595a8fc310488263ce888c7 Author: Anton Blanchard <anton <at> samba.org> Date: Tue Mar 12 01:51:51 2013 +0000 Without that commit, I can not boot my G5, thus I can't run automated tests on it against my queue. Could you please merge kvm/next against linus/master, so that I can base my trees against that?" * upstream/master: (653 commits) PCI: Use ROM images from firmware only if no other ROM source available sparc: remove unused "config BITS" sparc: delete "if !ULTRA_HAS_POPULATION_COUNT" KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798) KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions (CVE-2013-1797) KVM: x86: fix for buffer overflow in handling of MSR_KVM_SYSTEM_TIME (CVE-2013-1796) arm64: Kconfig.debug: Remove unused CONFIG_DEBUG_ERRORS arm64: Do not select GENERIC_HARDIRQS_NO_DEPRECATED inet: limit length of fragment queue hash table bucket lists qeth: Fix scatter-gather regression qeth: Fix invalid router settings handling qeth: delay feature trace sgy-cts1000: Remove __dev* attributes KVM: x86: fix deadlock in clock-in-progress request handling KVM: allow host header to be included even for !CONFIG_KVM hwmon: (lm75) Fix tcn75 prefix hwmon: (lm75.h) Update header inclusion MAINTAINERS: Remove Mark M. Hoffman xfs: ensure we capture IO errors correctly xfs: fix xfs_iomap_eof_prealloc_initial_size type ... Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c27
1 files changed, 24 insertions, 3 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c2e2c2310374..1f835a83cb2c 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2400,6 +2400,27 @@ static void test_ftrace_alive(struct seq_file *m)
seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n");
}
+#ifdef CONFIG_TRACER_MAX_TRACE
+static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter)
+{
+ if (iter->trace->allocated_snapshot)
+ seq_printf(m, "#\n# * Snapshot is allocated *\n#\n");
+ else
+ seq_printf(m, "#\n# * Snapshot is freed *\n#\n");
+
+ seq_printf(m, "# Snapshot commands:\n");
+ seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n");
+ seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
+ seq_printf(m, "# Takes a snapshot of the main buffer.\n");
+ seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
+ seq_printf(m, "# is not a '0' or '1')\n");
+}
+#else
+/* Should never be called */
+static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { }
+#endif
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
@@ -2411,7 +2432,9 @@ static int s_show(struct seq_file *m, void *v)
seq_puts(m, "#\n");
test_ftrace_alive(m);
}
- if (iter->trace && iter->trace->print_header)
+ if (iter->snapshot && trace_empty(iter))
+ print_snapshot_help(m, iter);
+ else if (iter->trace && iter->trace->print_header)
iter->trace->print_header(m);
else
trace_default_header(m);
@@ -4144,8 +4167,6 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
default:
if (current_trace->allocated_snapshot)
tracing_reset_online_cpus(&max_tr);
- else
- ret = -EINVAL;
break;
}