From 2743a5b0fa6f309da904f2190a9cc25deee34dbd Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Wed, 4 Mar 2009 20:36:51 +1100 Subject: perfcounters: provide expansion room in the ABI Impact: ABI change This expands several fields in the perf_counter_hw_event struct and adds a "flags" argument to the perf_counter_open system call, in order that features can be added in future without ABI changes. In particular the record_type field is expanded to 64 bits, and the space for flag bits has been expanded from 32 to 64 bits. This also adds some new fields: * read_format (64 bits) is intended to provide a way to specify what userspace wants to get back when it does a read() on a simple (non-interrupting) counter; * exclude_idle (1 bit) provides a way for userspace to ask that events that occur when the cpu is idle be excluded; * extra_config_len will provide a way for userspace to supply an arbitrary amount of extra machine-specific PMU configuration data immediately following the perf_counter_hw_event struct, to allow sophisticated users to program things such as instruction matching CAMs and address range registers; * __reserved_3 and __reserved_4 provide space for future expansion. Signed-off-by: Paul Mackerras --- include/linux/syscalls.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/syscalls.h') diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 28ef2be..ab1d772 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -698,5 +698,5 @@ int kernel_execve(const char *filename, char *const argv[], char *const envp[]); asmlinkage long sys_perf_counter_open( const struct perf_counter_hw_event __user *hw_event_uptr, - pid_t pid, int cpu, int group_fd); + pid_t pid, int cpu, int group_fd, unsigned long flags); #endif -- cgit v1.1