6.1-stable review patch. If anyone has any objections, please let me know.
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From: Masami Hiramatsu (Google) mhiramat@kernel.org
[ Upstream commit 59a7a298565aa0ce44ce8e4fbcbb89a19730013a ]
Add nr_maxactive to specify rethook_node pool size. This means the maximum number of actively running target functions concurrently for probing by exit_handler. Note that if the running function is preempted or sleep, it is still counted as 'active'.
Link: https://lkml.kernel.org/r/167526697917.433354.17779774988245113106.stgit@mhi...
Cc: Florent Revest revest@chromium.org Cc: Mark Rutland mark.rutland@arm.com Cc: Will Deacon will@kernel.org Signed-off-by: Masami Hiramatsu (Google) mhiramat@kernel.org Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Stable-dep-of: 700b2b439766 ("fprobe: Fix to ensure the number of active retprobes is not zero") Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/fprobe.h | 2 ++ kernel/trace/fprobe.c | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index e0d4e61362491..678f741a7b330 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -14,6 +14,7 @@ * @flags: The status flag. * @rethook: The rethook data structure. (internal data) * @entry_data_size: The private data storage size. + * @nr_maxactive: The max number of active functions. * @entry_handler: The callback function for function entry. * @exit_handler: The callback function for function exit. */ @@ -31,6 +32,7 @@ struct fprobe { unsigned int flags; struct rethook *rethook; size_t entry_data_size; + int nr_maxactive;
void (*entry_handler)(struct fprobe *fp, unsigned long entry_ip, struct pt_regs *regs, void *entry_data); diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index be28d1bc84e80..441a373079213 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -143,7 +143,10 @@ static int fprobe_init_rethook(struct fprobe *fp, int num) }
/* Initialize rethook if needed */ - size = num * num_possible_cpus() * 2; + if (fp->nr_maxactive) + size = fp->nr_maxactive; + else + size = num * num_possible_cpus() * 2; if (size < 0) return -E2BIG;