Hi,
These patches add signal related tracepoints including
signal generation, delivery, and loss. First patch also
moves signal-sending tracepoint from events/sched.h to
events/signal.h.
Changes in v4
- Fix typo of task_struct pointer
Changes in v3
- Add Docbook style comments
Changes in v2
- Add siginfo arguments
Thank you,
---
Masami Hiramatsu (3):
tracepoint: Add signal loss events
tracepoint: Add signal deliver event
tracepoint: Move signal sending tracepoint to events/signal.h
Documentation/DocBook/tracepoint.tmpl | 5 +
include/trace/events/sched.h | 25 -----
include/trace/events/signal.h | 173 +++++++++++++++++++++++++++++++++
kernel/signal.c | 27 ++++-
4 files changed, 198 insertions(+), 32 deletions(-)
create mode 100644 include/trace/events/signal.h
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division
e-mail: [email protected]
Move signal sending event to events/signal.h. This patch also renames
sched_signal_send event to signal_generate.
Changes in v4:
- Fix a typo of task_struct pointer.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Add siginfo argument
- Add siginfo storing macro
Signed-off-by: Masami Hiramatsu <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Roland McGrath <[email protected]>
Cc: Ingo Molnar <[email protected]>
---
Documentation/DocBook/tracepoint.tmpl | 5 +++
include/trace/events/sched.h | 25 -------------
include/trace/events/signal.h | 66 +++++++++++++++++++++++++++++++++
kernel/signal.c | 5 ++-
4 files changed, 74 insertions(+), 27 deletions(-)
create mode 100644 include/trace/events/signal.h
diff --git a/Documentation/DocBook/tracepoint.tmpl b/Documentation/DocBook/tracepoint.tmpl
index b0756d0..8bca1d5 100644
--- a/Documentation/DocBook/tracepoint.tmpl
+++ b/Documentation/DocBook/tracepoint.tmpl
@@ -86,4 +86,9 @@
!Iinclude/trace/events/irq.h
</chapter>
+ <chapter id="signal">
+ <title>SIGNAL</title>
+!Iinclude/trace/events/signal.h
+ </chapter>
+
</book>
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index b50b985..b221bb3 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -320,31 +320,6 @@ TRACE_EVENT(sched_process_fork,
);
/*
- * Tracepoint for sending a signal:
- */
-TRACE_EVENT(sched_signal_send,
-
- TP_PROTO(int sig, struct task_struct *p),
-
- TP_ARGS(sig, p),
-
- TP_STRUCT__entry(
- __field( int, sig )
- __array( char, comm, TASK_COMM_LEN )
- __field( pid_t, pid )
- ),
-
- TP_fast_assign(
- memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
- __entry->pid = p->pid;
- __entry->sig = sig;
- ),
-
- TP_printk("sig=%d comm=%s pid=%d",
- __entry->sig, __entry->comm, __entry->pid)
-);
-
-/*
* XXX the below sched_stat tracepoints only apply to SCHED_OTHER/BATCH/IDLE
* adding sched_stat support to SCHED_FIFO/RR would be welcome.
*/
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
new file mode 100644
index 0000000..ef51756
--- /dev/null
+++ b/include/trace/events/signal.h
@@ -0,0 +1,66 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM signal
+
+#if !defined(_TRACE_SIGNAL_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SIGNAL_H
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/tracepoint.h>
+
+#define TP_STORE_SIGINFO(__entry, info) \
+ do { \
+ if (info == SEND_SIG_NOINFO) { \
+ __entry->errno = 0; \
+ __entry->code = SI_USER; \
+ } else if (info == SEND_SIG_PRIV) { \
+ __entry->errno = 0; \
+ __entry->code = SI_KERNEL; \
+ } else { \
+ __entry->errno = info->si_errno; \
+ __entry->code = info->si_code; \
+ } \
+ } while (0)
+
+/**
+ * signal_generate - called when a signal is generated
+ * @sig: signal number
+ * @info: pointer to struct siginfo
+ * @task: pointer to struct task_struct
+ *
+ * Current process sends a 'sig' signal to 'task' process with
+ * 'info' siginfo. If 'info' is SEND_SIG_NOINFO or SEND_SIG_PRIV,
+ * 'info' is not a pointer and you can't access its field. Instead,
+ * SEND_SIG_NOINFO means that si_code is SI_USER, and SEND_SIG_PRIV
+ * means that si_code is SI_KERNEL.
+ */
+TRACE_EVENT(signal_generate,
+
+ TP_PROTO(int sig, struct siginfo *info, struct task_struct *task),
+
+ TP_ARGS(sig, info, task),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, errno )
+ __field( int, code )
+ __array( char, comm, TASK_COMM_LEN )
+ __field( pid_t, pid )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ TP_STORE_SIGINFO(__entry, info);
+ memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
+ __entry->pid = task->pid;
+ ),
+
+ TP_printk("sig=%d errno=%d code=%d comm=%s pid=%d",
+ __entry->sig, __entry->errno, __entry->code,
+ __entry->comm, __entry->pid)
+);
+
+#endif /* _TRACE_SIGNAL_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/kernel/signal.c b/kernel/signal.c
index fe08008..54ac4c5 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -28,7 +28,8 @@
#include <linux/freezer.h>
#include <linux/pid_namespace.h>
#include <linux/nsproxy.h>
-#include <trace/events/sched.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/signal.h>
#include <asm/param.h>
#include <asm/uaccess.h>
@@ -856,7 +857,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
struct sigqueue *q;
int override_rlimit;
- trace_sched_signal_send(sig, t);
+ trace_signal_generate(sig, info, t);
assert_spin_locked(&t->sighand->siglock);
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division
e-mail: [email protected]
Add a tracepoint where a process gets a signal. This tracepoint
shows signal-number, sa-handler and sa-flag.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Add siginfo argument
- Fix comment
Signed-off-by: Masami Hiramatsu <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Roland McGrath <[email protected]>
Cc: Ingo Molnar <[email protected]>
---
include/trace/events/signal.h | 39 +++++++++++++++++++++++++++++++++++++++
kernel/signal.c | 3 +++
2 files changed, 42 insertions(+), 0 deletions(-)
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index ef51756..a6d71de 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -60,6 +60,45 @@ TRACE_EVENT(signal_generate,
__entry->comm, __entry->pid)
);
+/**
+ * signal_deliver - called when a signal is delivered
+ * @sig: signal number
+ * @info: pointer to struct siginfo
+ * @ka: pointer to struct k_sigaction
+ *
+ * A 'sig' signal is delivered to current process with 'info' siginfo,
+ * and it will be handled by 'ka'. ka->sa.sa_handler can be SIG_IGN or
+ * SIG_DFL.
+ * Note that some signals reported by signal_generate tracepoint can be
+ * lost, ignored or modified (by debugger) before hitting this tracepoint.
+ * This means, this can show which signals are actually delivered, but
+ * matching generated signals and delivered signals may not be correct.
+ */
+TRACE_EVENT(signal_deliver,
+
+ TP_PROTO(int sig, struct siginfo *info, struct k_sigaction *ka),
+
+ TP_ARGS(sig, info, ka),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, errno )
+ __field( int, code )
+ __field( unsigned long, sa_handler )
+ __field( unsigned long, sa_flags )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ TP_STORE_SIGINFO(__entry, info);
+ __entry->sa_handler = (unsigned long)ka->sa.sa_handler;
+ __entry->sa_flags = ka->sa.sa_flags;
+ ),
+
+ TP_printk("sig=%d errno=%d code=%d sa_handler=%lx sa_flags=%lx",
+ __entry->sig, __entry->errno, __entry->code,
+ __entry->sa_handler, __entry->sa_flags)
+);
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */
diff --git a/kernel/signal.c b/kernel/signal.c
index 54ac4c5..d518984 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1860,6 +1860,9 @@ relock:
ka = &sighand->action[signr-1];
}
+ /* Trace actually delivered signals. */
+ trace_signal_deliver(signr, info, ka);
+
if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */
continue;
if (ka->sa.sa_handler != SIG_DFL) {
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division
e-mail: [email protected]
Add signal_overflow_fail and signal_lose_info tracepoints
for signal-lost events.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Use siginfo string macro
Signed-off-by: Masami Hiramatsu <[email protected]>
Suggested-by: Roland McGrath <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Ingo Molnar <[email protected]>
---
include/trace/events/signal.h | 68 +++++++++++++++++++++++++++++++++++++++++
kernel/signal.c | 19 ++++++++---
2 files changed, 82 insertions(+), 5 deletions(-)
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index a6d71de..a510b75 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -99,6 +99,74 @@ TRACE_EVENT(signal_deliver,
__entry->sig, __entry->errno, __entry->code,
__entry->sa_handler, __entry->sa_flags)
);
+
+/**
+ * signal_overflow_fail - called when signal queue is overflow
+ * @sig: signal number
+ * @group: signal to process group or not (bool)
+ * @info: pointer to struct siginfo
+ *
+ * Kernel fails to generate 'sig' signal with 'info' siginfo, because
+ * siginfo queue is overflow, and the signal is dropped.
+ * 'group' is not 0 if the signal will be sent to a process group.
+ * 'sig' is always one of RT signals.
+ */
+TRACE_EVENT(signal_overflow_fail,
+
+ TP_PROTO(int sig, int group, struct siginfo *info),
+
+ TP_ARGS(sig, group, info),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, group )
+ __field( int, errno )
+ __field( int, code )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ __entry->group = group;
+ TP_STORE_SIGINFO(__entry, info);
+ ),
+
+ TP_printk("sig=%d group=%d errno=%d code=%d",
+ __entry->sig, __entry->group, __entry->errno, __entry->code)
+);
+
+/**
+ * signal_lose_info - called when siginfo is lost
+ * @sig: signal number
+ * @group: signal to process group or not (bool)
+ * @info: pointer to struct siginfo
+ *
+ * Kernel generates 'sig' signal but loses 'info' siginfo, because siginfo
+ * queue is overflow.
+ * 'group' is not 0 if the signal will be sent to a process group.
+ * 'sig' is always one of non-RT signals.
+ */
+TRACE_EVENT(signal_lose_info,
+
+ TP_PROTO(int sig, int group, struct siginfo *info),
+
+ TP_ARGS(sig, group, info),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, group )
+ __field( int, errno )
+ __field( int, code )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ __entry->group = group;
+ TP_STORE_SIGINFO(__entry, info);
+ ),
+
+ TP_printk("sig=%d group=%d errno=%d code=%d",
+ __entry->sig, __entry->group, __entry->errno, __entry->code)
+);
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */
diff --git a/kernel/signal.c b/kernel/signal.c
index d518984..6b982f2 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -919,12 +919,21 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
break;
}
} else if (!is_si_special(info)) {
- if (sig >= SIGRTMIN && info->si_code != SI_USER)
- /*
- * Queue overflow, abort. We may abort if the signal was rt
- * and sent by user using something other than kill().
- */
+ if (sig >= SIGRTMIN && info->si_code != SI_USER) {
+ /*
+ * Queue overflow, abort. We may abort if the
+ * signal was rt and sent by user using something
+ * other than kill().
+ */
+ trace_signal_overflow_fail(sig, group, info);
return -EAGAIN;
+ } else {
+ /*
+ * This is a silent loss of information. We still
+ * send the signal, but the *info bits are lost.
+ */
+ trace_signal_lose_info(sig, group, info);
+ }
}
out_set:
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division
e-mail: [email protected]
Acked-by: Roland McGrath <[email protected]>
There might be some more refinements that are worthwhile, but these look
like a sensible and clean enough set of tracepoints to start with. If we
need to change them, that will become clear from the experiences of people
actually using these.
Thanks,
Roland
Commit-ID: d1eb650ff4130972fa21462fa49cd35a2865403b
Gitweb: http://git.kernel.org/tip/d1eb650ff4130972fa21462fa49cd35a2865403b
Author: Masami Hiramatsu <[email protected]>
AuthorDate: Tue, 24 Nov 2009 16:56:45 -0500
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 26 Nov 2009 10:55:37 +0100
tracepoint: Move signal sending tracepoint to events/signal.h
Move signal sending event to events/signal.h. This patch also
renames sched_signal_send event to signal_generate.
Changes in v4:
- Fix a typo of task_struct pointer.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Add siginfo argument
- Add siginfo storing macro
Signed-off-by: Masami Hiramatsu <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Cc: systemtap <[email protected]>
Cc: DLE <[email protected]>
Cc: Oleg Nesterov <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
Documentation/DocBook/tracepoint.tmpl | 5 ++
include/trace/events/sched.h | 25 ------------
include/trace/events/signal.h | 66 +++++++++++++++++++++++++++++++++
kernel/signal.c | 5 +-
4 files changed, 74 insertions(+), 27 deletions(-)
diff --git a/Documentation/DocBook/tracepoint.tmpl b/Documentation/DocBook/tracepoint.tmpl
index b0756d0..8bca1d5 100644
--- a/Documentation/DocBook/tracepoint.tmpl
+++ b/Documentation/DocBook/tracepoint.tmpl
@@ -86,4 +86,9 @@
!Iinclude/trace/events/irq.h
</chapter>
+ <chapter id="signal">
+ <title>SIGNAL</title>
+!Iinclude/trace/events/signal.h
+ </chapter>
+
</book>
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 9d316b2..cfceb0b 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -288,31 +288,6 @@ TRACE_EVENT(sched_process_fork,
);
/*
- * Tracepoint for sending a signal:
- */
-TRACE_EVENT(sched_signal_send,
-
- TP_PROTO(int sig, struct task_struct *p),
-
- TP_ARGS(sig, p),
-
- TP_STRUCT__entry(
- __field( int, sig )
- __array( char, comm, TASK_COMM_LEN )
- __field( pid_t, pid )
- ),
-
- TP_fast_assign(
- memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
- __entry->pid = p->pid;
- __entry->sig = sig;
- ),
-
- TP_printk("sig=%d comm=%s pid=%d",
- __entry->sig, __entry->comm, __entry->pid)
-);
-
-/*
* XXX the below sched_stat tracepoints only apply to SCHED_OTHER/BATCH/IDLE
* adding sched_stat support to SCHED_FIFO/RR would be welcome.
*/
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
new file mode 100644
index 0000000..ef51756
--- /dev/null
+++ b/include/trace/events/signal.h
@@ -0,0 +1,66 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM signal
+
+#if !defined(_TRACE_SIGNAL_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SIGNAL_H
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/tracepoint.h>
+
+#define TP_STORE_SIGINFO(__entry, info) \
+ do { \
+ if (info == SEND_SIG_NOINFO) { \
+ __entry->errno = 0; \
+ __entry->code = SI_USER; \
+ } else if (info == SEND_SIG_PRIV) { \
+ __entry->errno = 0; \
+ __entry->code = SI_KERNEL; \
+ } else { \
+ __entry->errno = info->si_errno; \
+ __entry->code = info->si_code; \
+ } \
+ } while (0)
+
+/**
+ * signal_generate - called when a signal is generated
+ * @sig: signal number
+ * @info: pointer to struct siginfo
+ * @task: pointer to struct task_struct
+ *
+ * Current process sends a 'sig' signal to 'task' process with
+ * 'info' siginfo. If 'info' is SEND_SIG_NOINFO or SEND_SIG_PRIV,
+ * 'info' is not a pointer and you can't access its field. Instead,
+ * SEND_SIG_NOINFO means that si_code is SI_USER, and SEND_SIG_PRIV
+ * means that si_code is SI_KERNEL.
+ */
+TRACE_EVENT(signal_generate,
+
+ TP_PROTO(int sig, struct siginfo *info, struct task_struct *task),
+
+ TP_ARGS(sig, info, task),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, errno )
+ __field( int, code )
+ __array( char, comm, TASK_COMM_LEN )
+ __field( pid_t, pid )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ TP_STORE_SIGINFO(__entry, info);
+ memcpy(__entry->comm, task->comm, TASK_COMM_LEN);
+ __entry->pid = task->pid;
+ ),
+
+ TP_printk("sig=%d errno=%d code=%d comm=%s pid=%d",
+ __entry->sig, __entry->errno, __entry->code,
+ __entry->comm, __entry->pid)
+);
+
+#endif /* _TRACE_SIGNAL_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/kernel/signal.c b/kernel/signal.c
index 6705320..a1e0cc6 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -27,7 +27,8 @@
#include <linux/freezer.h>
#include <linux/pid_namespace.h>
#include <linux/nsproxy.h>
-#include <trace/events/sched.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/signal.h>
#include <asm/param.h>
#include <asm/uaccess.h>
@@ -834,7 +835,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
struct sigqueue *q;
int override_rlimit;
- trace_sched_signal_send(sig, t);
+ trace_signal_generate(sig, info, t);
assert_spin_locked(&t->sighand->siglock);
Commit-ID: f9d4257e01d266e67420cc99d456b6d4c8464f54
Gitweb: http://git.kernel.org/tip/f9d4257e01d266e67420cc99d456b6d4c8464f54
Author: Masami Hiramatsu <[email protected]>
AuthorDate: Tue, 24 Nov 2009 16:56:51 -0500
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 26 Nov 2009 10:55:38 +0100
tracepoint: Add signal deliver event
Add a tracepoint where a process gets a signal. This tracepoint
shows signal-number, sa-handler and sa-flag.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Add siginfo argument
- Fix comment
Signed-off-by: Masami Hiramatsu <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Cc: systemtap <[email protected]>
Cc: DLE <[email protected]>
Cc: Oleg Nesterov <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
include/trace/events/signal.h | 39 +++++++++++++++++++++++++++++++++++++++
kernel/signal.c | 3 +++
2 files changed, 42 insertions(+), 0 deletions(-)
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index ef51756..a6d71de 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -60,6 +60,45 @@ TRACE_EVENT(signal_generate,
__entry->comm, __entry->pid)
);
+/**
+ * signal_deliver - called when a signal is delivered
+ * @sig: signal number
+ * @info: pointer to struct siginfo
+ * @ka: pointer to struct k_sigaction
+ *
+ * A 'sig' signal is delivered to current process with 'info' siginfo,
+ * and it will be handled by 'ka'. ka->sa.sa_handler can be SIG_IGN or
+ * SIG_DFL.
+ * Note that some signals reported by signal_generate tracepoint can be
+ * lost, ignored or modified (by debugger) before hitting this tracepoint.
+ * This means, this can show which signals are actually delivered, but
+ * matching generated signals and delivered signals may not be correct.
+ */
+TRACE_EVENT(signal_deliver,
+
+ TP_PROTO(int sig, struct siginfo *info, struct k_sigaction *ka),
+
+ TP_ARGS(sig, info, ka),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, errno )
+ __field( int, code )
+ __field( unsigned long, sa_handler )
+ __field( unsigned long, sa_flags )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ TP_STORE_SIGINFO(__entry, info);
+ __entry->sa_handler = (unsigned long)ka->sa.sa_handler;
+ __entry->sa_flags = ka->sa.sa_flags;
+ ),
+
+ TP_printk("sig=%d errno=%d code=%d sa_handler=%lx sa_flags=%lx",
+ __entry->sig, __entry->errno, __entry->code,
+ __entry->sa_handler, __entry->sa_flags)
+);
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */
diff --git a/kernel/signal.c b/kernel/signal.c
index a1e0cc6..349d449 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1840,6 +1840,9 @@ relock:
ka = &sighand->action[signr-1];
}
+ /* Trace actually delivered signals. */
+ trace_signal_deliver(signr, info, ka);
+
if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */
continue;
if (ka->sa.sa_handler != SIG_DFL) {
Commit-ID: ba005e1f417295d28cd1563ab82bc33af07fb16a
Gitweb: http://git.kernel.org/tip/ba005e1f417295d28cd1563ab82bc33af07fb16a
Author: Masami Hiramatsu <[email protected]>
AuthorDate: Tue, 24 Nov 2009 16:56:58 -0500
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 26 Nov 2009 10:55:38 +0100
tracepoint: Add signal loss events
Add signal_overflow_fail and signal_lose_info tracepoints
for signal-lost events.
Changes in v3:
- Add docbook style comments
Changes in v2:
- Use siginfo string macro
Suggested-by: Roland McGrath <[email protected]>
Reviewed-by: Jason Baron <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Cc: systemtap <[email protected]>
Cc: DLE <[email protected]>
Cc: Oleg Nesterov <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
include/trace/events/signal.h | 68 +++++++++++++++++++++++++++++++++++++++++
kernel/signal.c | 19 ++++++++---
2 files changed, 82 insertions(+), 5 deletions(-)
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index a6d71de..a510b75 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -99,6 +99,74 @@ TRACE_EVENT(signal_deliver,
__entry->sig, __entry->errno, __entry->code,
__entry->sa_handler, __entry->sa_flags)
);
+
+/**
+ * signal_overflow_fail - called when signal queue is overflow
+ * @sig: signal number
+ * @group: signal to process group or not (bool)
+ * @info: pointer to struct siginfo
+ *
+ * Kernel fails to generate 'sig' signal with 'info' siginfo, because
+ * siginfo queue is overflow, and the signal is dropped.
+ * 'group' is not 0 if the signal will be sent to a process group.
+ * 'sig' is always one of RT signals.
+ */
+TRACE_EVENT(signal_overflow_fail,
+
+ TP_PROTO(int sig, int group, struct siginfo *info),
+
+ TP_ARGS(sig, group, info),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, group )
+ __field( int, errno )
+ __field( int, code )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ __entry->group = group;
+ TP_STORE_SIGINFO(__entry, info);
+ ),
+
+ TP_printk("sig=%d group=%d errno=%d code=%d",
+ __entry->sig, __entry->group, __entry->errno, __entry->code)
+);
+
+/**
+ * signal_lose_info - called when siginfo is lost
+ * @sig: signal number
+ * @group: signal to process group or not (bool)
+ * @info: pointer to struct siginfo
+ *
+ * Kernel generates 'sig' signal but loses 'info' siginfo, because siginfo
+ * queue is overflow.
+ * 'group' is not 0 if the signal will be sent to a process group.
+ * 'sig' is always one of non-RT signals.
+ */
+TRACE_EVENT(signal_lose_info,
+
+ TP_PROTO(int sig, int group, struct siginfo *info),
+
+ TP_ARGS(sig, group, info),
+
+ TP_STRUCT__entry(
+ __field( int, sig )
+ __field( int, group )
+ __field( int, errno )
+ __field( int, code )
+ ),
+
+ TP_fast_assign(
+ __entry->sig = sig;
+ __entry->group = group;
+ TP_STORE_SIGINFO(__entry, info);
+ ),
+
+ TP_printk("sig=%d group=%d errno=%d code=%d",
+ __entry->sig, __entry->group, __entry->errno, __entry->code)
+);
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */
diff --git a/kernel/signal.c b/kernel/signal.c
index 349d449..93e72e5 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -897,12 +897,21 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
break;
}
} else if (!is_si_special(info)) {
- if (sig >= SIGRTMIN && info->si_code != SI_USER)
- /*
- * Queue overflow, abort. We may abort if the signal was rt
- * and sent by user using something other than kill().
- */
+ if (sig >= SIGRTMIN && info->si_code != SI_USER) {
+ /*
+ * Queue overflow, abort. We may abort if the
+ * signal was rt and sent by user using something
+ * other than kill().
+ */
+ trace_signal_overflow_fail(sig, group, info);
return -EAGAIN;
+ } else {
+ /*
+ * This is a silent loss of information. We still
+ * send the signal, but the *info bits are lost.
+ */
+ trace_signal_lose_info(sig, group, info);
+ }
}
out_set: