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author | Eric W. Biederman <ebiederm@xmission.com> | 2017-06-04 11:32:13 +0200 |
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committer | Eric W. Biederman <ebiederm@xmission.com> | 2018-07-21 17:43:12 +0200 |
commit | 6883f81aac6f44e7df70a6af189b3689ff52cbfb (patch) | |
tree | 184e376d23aa5ea7321e22f23dd78a3c77c74a63 /arch | |
parent | pids: Move the pgrp and session pid pointers from task_struct to signal_struct (diff) | |
download | linux-6883f81aac6f44e7df70a6af189b3689ff52cbfb.tar.xz linux-6883f81aac6f44e7df70a6af189b3689ff52cbfb.zip |
pid: Implement PIDTYPE_TGID
Everywhere except in the pid array we distinguish between a tasks pid and
a tasks tgid (thread group id). Even in the enumeration we want that
distinction sometimes so we have added __PIDTYPE_TGID. With leader_pid
we almost have an implementation of PIDTYPE_TGID in struct signal_struct.
Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
into the pids array. Then remove the __PIDTYPE_TGID special case and the
leader_pid in signal_struct.
The net size increase is just an extra pointer added to struct pid and
an extra pair of pointers of an hlist_node added to task_struct.
The effect on code maintenance is the removal of a number of special
cases today and the potential to remove many more special cases as
PIDTYPE_TGID gets used to it's fullest. The long term potential
is allowing zombie thread group leaders to exit, which will remove
a lot more special cases in the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/ia64/kernel/asm-offsets.c | 2 | ||||
-rw-r--r-- | arch/ia64/kernel/fsys.S | 4 | ||||
-rw-r--r-- | arch/s390/kernel/perf_cpum_sf.c | 2 |
3 files changed, 4 insertions, 4 deletions
diff --git a/arch/ia64/kernel/asm-offsets.c b/arch/ia64/kernel/asm-offsets.c index c1f8a57855af..00e8e2a1eb19 100644 --- a/arch/ia64/kernel/asm-offsets.c +++ b/arch/ia64/kernel/asm-offsets.c @@ -67,7 +67,7 @@ void foo(void) DEFINE(IA64_SIGNAL_GROUP_STOP_COUNT_OFFSET,offsetof (struct signal_struct, group_stop_count)); DEFINE(IA64_SIGNAL_SHARED_PENDING_OFFSET,offsetof (struct signal_struct, shared_pending)); - DEFINE(IA64_SIGNAL_LEADER_PID_OFFSET, offsetof (struct signal_struct, leader_pid)); + DEFINE(IA64_SIGNAL_PIDS_TGID_OFFSET, offsetof (struct signal_struct, pids[PIDTYPE_TGID])); BLANK(); diff --git a/arch/ia64/kernel/fsys.S b/arch/ia64/kernel/fsys.S index e85ebdac678b..d80c99a5f55d 100644 --- a/arch/ia64/kernel/fsys.S +++ b/arch/ia64/kernel/fsys.S @@ -68,10 +68,10 @@ ENTRY(fsys_getpid) add r9=TI_FLAGS+IA64_TASK_SIZE,r16 ;; ld4 r9=[r9] - add r17=IA64_SIGNAL_LEADER_PID_OFFSET,r17 + add r17=IA64_SIGNAL_PIDS_TGID_OFFSET,r17 ;; and r9=TIF_ALLWORK_MASK,r9 - ld8 r17=[r17] // r17 = current->signal->leader_pid + ld8 r17=[r17] // r17 = current->signal->pids[PIDTYPE_TGID] ;; add r8=IA64_PID_LEVEL_OFFSET,r17 ;; diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 0292d68e7dde..ca0b7ae894bb 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -665,7 +665,7 @@ static void cpumsf_output_event_pid(struct perf_event *event, goto out; /* Update the process ID (see also kernel/events/core.c) */ - data->tid_entry.pid = cpumsf_pid_type(event, pid, __PIDTYPE_TGID); + data->tid_entry.pid = cpumsf_pid_type(event, pid, PIDTYPE_TGID); data->tid_entry.tid = cpumsf_pid_type(event, pid, PIDTYPE_PID); perf_output_sample(&handle, &header, data, event); |