1. 13 3月, 2010 2 次提交
    • C
      Add generic sys_olduname() · 5cacdb4a
      Christoph Hellwig 提交于
      Add generic implementations of the old and really old uname system calls.
      Note that sh only implements sys_olduname but not sys_oldolduname, but I'm
      not going to bother with another ifdef for that special case.
      
      m32r implemented an old uname but never wired it up, so kill it, too.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: James Morris <jmorris@namei.org>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5cacdb4a
    • C
      improve sys_newuname() for compat architectures · e28cbf22
      Christoph Hellwig 提交于
      On an architecture that supports 32-bit compat we need to override the
      reported machine in uname with the 32-bit value.  Instead of doing this
      separately in every architecture introduce a COMPAT_UTS_MACHINE define in
      <asm/compat.h> and apply it directly in sys_newuname().
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: James Morris <jmorris@namei.org>
      Cc: Andreas Schwab <schwab@linux-m68k.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e28cbf22
  2. 07 3月, 2010 1 次提交
  3. 23 2月, 2010 1 次提交
  4. 21 1月, 2010 1 次提交
  5. 16 12月, 2009 1 次提交
  6. 11 12月, 2009 1 次提交
    • T
      sys: Fix missing rcu protection for __task_cred() access · d4581a23
      Thomas Gleixner 提交于
      commit c69e8d9c (CRED: Use RCU to access another task's creds and to
      release a task's own creds) added non rcu_read_lock() protected access
      to task creds of the target task in set_prio_one().
      
      The comment above the function says:
       * - the caller must hold the RCU read lock
      
      The calling code in sys_setpriority does read_lock(&tasklist_lock) but
      not rcu_read_lock(). This works only when CONFIG_TREE_PREEMPT_RCU=n.
      With CONFIG_TREE_PREEMPT_RCU=y the rcu_callbacks can run in the tick
      interrupt when they see no read side critical section.
      
      There is another instance of __task_cred() in sys_setpriority() itself
      which is equally unprotected.
      
      Wrap the whole code section into a rcu read side critical section to
      fix this quick and dirty.
      
      Will be revisited in course of the read_lock(&tasklist_lock) -> rcu
      crusade.
      
      Oleg noted further:
      
      This also fixes another bug here. find_task_by_vpid() is not safe
      without rcu_read_lock(). I do not mean it is not safe to use the
      result, just find_pid_ns() by itself is not safe.
      
      Usually tasklist gives enough protection, but if copy_process() fails
      it calls free_pid() lockless and does call_rcu(delayed_put_pid().
      This means, without rcu lock find_pid_ns() can't scan the hash table
      safely.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      LKML-Reference: <20091210004703.029784964@linutronix.de>
      Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      d4581a23
  7. 03 12月, 2009 1 次提交
    • H
      sched, cputime: Introduce thread_group_times() · 0cf55e1e
      Hidetoshi Seto 提交于
      This is a real fix for problem of utime/stime values decreasing
      described in the thread:
      
         http://lkml.org/lkml/2009/11/3/522
      
      Now cputime is accounted in the following way:
      
       - {u,s}time in task_struct are increased every time when the thread
         is interrupted by a tick (timer interrupt).
      
       - When a thread exits, its {u,s}time are added to signal->{u,s}time,
         after adjusted by task_times().
      
       - When all threads in a thread_group exits, accumulated {u,s}time
         (and also c{u,s}time) in signal struct are added to c{u,s}time
         in signal struct of the group's parent.
      
      So {u,s}time in task struct are "raw" tick count, while
      {u,s}time and c{u,s}time in signal struct are "adjusted" values.
      
      And accounted values are used by:
      
       - task_times(), to get cputime of a thread:
         This function returns adjusted values that originates from raw
         {u,s}time and scaled by sum_exec_runtime that accounted by CFS.
      
       - thread_group_cputime(), to get cputime of a thread group:
         This function returns sum of all {u,s}time of living threads in
         the group, plus {u,s}time in the signal struct that is sum of
         adjusted cputimes of all exited threads belonged to the group.
      
      The problem is the return value of thread_group_cputime(),
      because it is mixed sum of "raw" value and "adjusted" value:
      
        group's {u,s}time = foreach(thread){{u,s}time} + exited({u,s}time)
      
      This misbehavior can break {u,s}time monotonicity.
      Assume that if there is a thread that have raw values greater
      than adjusted values (e.g. interrupted by 1000Hz ticks 50 times
      but only runs 45ms) and if it exits, cputime will decrease (e.g.
      -5ms).
      
      To fix this, we could do:
      
        group's {u,s}time = foreach(t){task_times(t)} + exited({u,s}time)
      
      But task_times() contains hard divisions, so applying it for
      every thread should be avoided.
      
      This patch fixes the above problem in the following way:
      
       - Modify thread's exit (= __exit_signal()) not to use task_times().
         It means {u,s}time in signal struct accumulates raw values instead
         of adjusted values.  As the result it makes thread_group_cputime()
         to return pure sum of "raw" values.
      
       - Introduce a new function thread_group_times(*task, *utime, *stime)
         that converts "raw" values of thread_group_cputime() to "adjusted"
         values, in same calculation procedure as task_times().
      
       - Modify group's exit (= wait_task_zombie()) to use this introduced
         thread_group_times().  It make c{u,s}time in signal struct to
         have adjusted values like before this patch.
      
       - Replace some thread_group_cputime() by thread_group_times().
         This replacements are only applied where conveys the "adjusted"
         cputime to users, and where already uses task_times() near by it.
         (i.e. sys_times(), getrusage(), and /proc/<PID>/stat.)
      
      This patch have a positive side effect:
      
       - Before this patch, if a group contains many short-life threads
         (e.g. runs 0.9ms and not interrupted by ticks), the group's
         cputime could be invisible since thread's cputime was accumulated
         after adjusted: imagine adjustment function as adj(ticks, runtime),
           {adj(0, 0.9) + adj(0, 0.9) + ....} = {0 + 0 + ....} = 0.
         After this patch it will not happen because the adjustment is
         applied after accumulated.
      
      v2:
       - remove if()s, put new variables into signal_struct.
      Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Spencer Candland <spencer@bluehost.com>
      Cc: Americo Wang <xiyou.wangcong@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      LKML-Reference: <4B162517.8040909@jp.fujitsu.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0cf55e1e
  8. 26 11月, 2009 1 次提交
    • H
      sched: Introduce task_times() to replace task_{u,s}time() pair · d180c5bc
      Hidetoshi Seto 提交于
      Functions task_{u,s}time() are called in pair in almost all
      cases.  However task_stime() is implemented to call task_utime()
      from its inside, so such paired calls run task_utime() twice.
      
      It means we do heavy divisions (div_u64 + do_div) twice to get
      utime and stime which can be obtained at same time by one set
      of divisions.
      
      This patch introduces a function task_times(*tsk, *utime,
      *stime) to retrieve utime and stime at once in better, optimized
      way.
      Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Spencer Candland <spencer@bluehost.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Cc: Americo Wang <xiyou.wangcong@gmail.com>
      LKML-Reference: <4B0E16AE.906@jp.fujitsu.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d180c5bc
  9. 29 10月, 2009 1 次提交
    • C
      connector: fix regression introduced by sid connector · 0d0df599
      Christian Borntraeger 提交于
      Since commit 02b51df1 (proc connector: add
      event for process becoming session leader) we have the following warning:
      
      Badness at kernel/softirq.c:143
      [...]
      Krnl PSW : 0404c00180000000 00000000001481d4 (local_bh_enable+0xb0/0xe0)
      [...]
      Call Trace:
      ([<000000013fe04100>] 0x13fe04100)
       [<000000000048a946>] sk_filter+0x9a/0xd0
       [<000000000049d938>] netlink_broadcast+0x2c0/0x53c
       [<00000000003ba9ae>] cn_netlink_send+0x272/0x2b0
       [<00000000003baef0>] proc_sid_connector+0xc4/0xd4
       [<0000000000142604>] __set_special_pids+0x58/0x90
       [<0000000000159938>] sys_setsid+0xb4/0xd8
       [<00000000001187fe>] sysc_noemu+0x10/0x16
       [<00000041616cb266>] 0x41616cb266
      
      The warning is
      --->    WARN_ON_ONCE(in_irq() || irqs_disabled());
      
      The network code must not be called with disabled interrupts but
      sys_setsid holds the tasklist_lock with spinlock_irq while calling the
      connector.
      
      After a discussion we agreed that we can move proc_sid_connector from
      __set_special_pids to sys_setsid.
      
      We also agreed that it is sufficient to change the check from
      task_session(curr) != pid into err > 0, since if we don't change the
      session, this means we were already the leader and return -EPERM.
      
      One last thing:
      There is also daemonize(), and some people might want to get a
      notification in that case. Since daemonize() is only needed if a user
      space does kernel_thread this does not look important (and there seems
      to be no consensus if this connector should be called in daemonize). If
      we really want this, we can add proc_sid_connector to daemonize() in an
      additional patch (Scott?)
      Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Cc: Scott James Remnant <scott@ubuntu.com>
      Cc: Matt Helsley <matthltc@us.ibm.com>
      Cc: David S. Miller <davem@davemloft.net>
      Acked-by: NOleg Nesterov <oleg@redhat.com>
      Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
      Acked-by: NDavid Rientjes <rientjes@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0d0df599
  10. 14 10月, 2009 1 次提交
  11. 04 10月, 2009 1 次提交
    • A
      HWPOISON: Clean up PR_MCE_KILL interface · 1087e9b4
      Andi Kleen 提交于
      While writing the manpage I noticed some shortcomings in the
      current interface.
      
      - Define symbolic names for all the different values
      - Boundary check the kill mode values
      - For symmetry add a get interface too. This allows library
      code to get/set the current state.
      - For consistency define a PR_MCE_KILL_DEFAULT value
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      1087e9b4
  12. 23 9月, 2009 1 次提交
    • J
      getrusage: fill ru_maxrss value · 1f10206c
      Jiri Pirko 提交于
      Make ->ru_maxrss value in struct rusage filled accordingly to rss hiwater
      mark.  This struct is filled as a parameter to getrusage syscall.
      ->ru_maxrss value is set to KBs which is the way it is done in BSD
      systems.  /usr/bin/time (gnu time) application converts ->ru_maxrss to KBs
      which seems to be incorrect behavior.  Maintainer of this util was
      notified by me with the patch which corrects it and cc'ed.
      
      To make this happen we extend struct signal_struct by two fields.  The
      first one is ->maxrss which we use to store rss hiwater of the task.  The
      second one is ->cmaxrss which we use to store highest rss hiwater of all
      task childs.  These values are used in k_getrusage() to actually fill
      ->ru_maxrss.  k_getrusage() uses current rss hiwater value directly if mm
      struct exists.
      
      Note:
      exec() clear mm->hiwater_rss, but doesn't clear sig->maxrss.
      it is intetionally behavior. *BSD getrusage have exec() inheriting.
      
      test programs
      ========================================================
      
      getrusage.c
      ===========
       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
       #include <sys/types.h>
       #include <sys/time.h>
       #include <sys/resource.h>
       #include <sys/types.h>
       #include <sys/wait.h>
       #include <unistd.h>
       #include <signal.h>
       #include <sys/mman.h>
      
       #include "common.h"
      
       #define err(str) perror(str), exit(1)
      
      int main(int argc, char** argv)
      {
      	int status;
      
      	printf("allocate 100MB\n");
      	consume(100);
      
      	printf("testcase1: fork inherit? \n");
      	printf("  expect: initial.self ~= child.self\n");
      	show_rusage("initial");
      	if (__fork()) {
      		wait(&status);
      	} else {
      		show_rusage("fork child");
      		_exit(0);
      	}
      	printf("\n");
      
      	printf("testcase2: fork inherit? (cont.) \n");
      	printf("  expect: initial.children ~= 100MB, but child.children = 0\n");
      	show_rusage("initial");
      	if (__fork()) {
      		wait(&status);
      	} else {
      		show_rusage("child");
      		_exit(0);
      	}
      	printf("\n");
      
      	printf("testcase3: fork + malloc \n");
      	printf("  expect: child.self ~= initial.self + 50MB\n");
      	show_rusage("initial");
      	if (__fork()) {
      		wait(&status);
      	} else {
      		printf("allocate +50MB\n");
      		consume(50);
      		show_rusage("fork child");
      		_exit(0);
      	}
      	printf("\n");
      
      	printf("testcase4: grandchild maxrss\n");
      	printf("  expect: post_wait.children ~= 300MB\n");
      	show_rusage("initial");
      	if (__fork()) {
      		wait(&status);
      		show_rusage("post_wait");
      	} else {
      		system("./child -n 0 -g 300");
      		_exit(0);
      	}
      	printf("\n");
      
      	printf("testcase5: zombie\n");
      	printf("  expect: pre_wait ~= initial, IOW the zombie process is not accounted.\n");
      	printf("          post_wait ~= 400MB, IOW wait() collect child's max_rss. \n");
      	show_rusage("initial");
      	if (__fork()) {
      		sleep(1); /* children become zombie */
      		show_rusage("pre_wait");
      		wait(&status);
      		show_rusage("post_wait");
      	} else {
      		system("./child -n 400");
      		_exit(0);
      	}
      	printf("\n");
      
      	printf("testcase6: SIG_IGN\n");
      	printf("  expect: initial ~= after_zombie (child's 500MB alloc should be ignored).\n");
      	show_rusage("initial");
      	signal(SIGCHLD, SIG_IGN);
      	if (__fork()) {
      		sleep(1); /* children become zombie */
      		show_rusage("after_zombie");
      	} else {
      		system("./child -n 500");
      		_exit(0);
      	}
      	printf("\n");
      	signal(SIGCHLD, SIG_DFL);
      
      	printf("testcase7: exec (without fork) \n");
      	printf("  expect: initial ~= exec \n");
      	show_rusage("initial");
      	execl("./child", "child", "-v", NULL);
      
      	return 0;
      }
      
      child.c
      =======
       #include <sys/types.h>
       #include <unistd.h>
       #include <sys/types.h>
       #include <sys/wait.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
       #include <sys/types.h>
       #include <sys/time.h>
       #include <sys/resource.h>
      
       #include "common.h"
      
      int main(int argc, char** argv)
      {
      	int status;
      	int c;
      	long consume_size = 0;
      	long grandchild_consume_size = 0;
      	int show = 0;
      
      	while ((c = getopt(argc, argv, "n:g:v")) != -1) {
      		switch (c) {
      		case 'n':
      			consume_size = atol(optarg);
      			break;
      		case 'v':
      			show = 1;
      			break;
      		case 'g':
      
      			grandchild_consume_size = atol(optarg);
      			break;
      		default:
      			break;
      		}
      	}
      
      	if (show)
      		show_rusage("exec");
      
      	if (consume_size) {
      		printf("child alloc %ldMB\n", consume_size);
      		consume(consume_size);
      	}
      
      	if (grandchild_consume_size) {
      		if (fork()) {
      			wait(&status);
      		} else {
      			printf("grandchild alloc %ldMB\n", grandchild_consume_size);
      			consume(grandchild_consume_size);
      
      			exit(0);
      		}
      	}
      
      	return 0;
      }
      
      common.c
      ========
       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
       #include <sys/types.h>
       #include <sys/time.h>
       #include <sys/resource.h>
       #include <sys/types.h>
       #include <sys/wait.h>
       #include <unistd.h>
       #include <signal.h>
       #include <sys/mman.h>
      
       #include "common.h"
       #define err(str) perror(str), exit(1)
      
      void show_rusage(char *prefix)
      {
          	int err, err2;
          	struct rusage rusage_self;
          	struct rusage rusage_children;
      
          	printf("%s: ", prefix);
          	err = getrusage(RUSAGE_SELF, &rusage_self);
          	if (!err)
          		printf("self %ld ", rusage_self.ru_maxrss);
          	err2 = getrusage(RUSAGE_CHILDREN, &rusage_children);
          	if (!err2)
          		printf("children %ld ", rusage_children.ru_maxrss);
      
          	printf("\n");
      }
      
      /* Some buggy OS need this worthless CPU waste. */
      void make_pagefault(void)
      {
      	void *addr;
      	int size = getpagesize();
      	int i;
      
      	for (i=0; i<1000; i++) {
      		addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
      		if (addr == MAP_FAILED)
      			err("make_pagefault");
      		memset(addr, 0, size);
      		munmap(addr, size);
      	}
      }
      
      void consume(int mega)
      {
          	size_t sz = mega * 1024 * 1024;
          	void *ptr;
      
          	ptr = malloc(sz);
          	memset(ptr, 0, sz);
      	make_pagefault();
      }
      
      pid_t __fork(void)
      {
      	pid_t pid;
      
      	pid = fork();
      	make_pagefault();
      
      	return pid;
      }
      
      common.h
      ========
      void show_rusage(char *prefix);
      void make_pagefault(void);
      void consume(int mega);
      pid_t __fork(void);
      
      FreeBSD result (expected result)
      ========================================================
      allocate 100MB
      testcase1: fork inherit?
        expect: initial.self ~= child.self
      initial: self 103492 children 0
      fork child: self 103540 children 0
      
      testcase2: fork inherit? (cont.)
        expect: initial.children ~= 100MB, but child.children = 0
      initial: self 103540 children 103540
      child: self 103564 children 0
      
      testcase3: fork + malloc
        expect: child.self ~= initial.self + 50MB
      initial: self 103564 children 103564
      allocate +50MB
      fork child: self 154860 children 0
      
      testcase4: grandchild maxrss
        expect: post_wait.children ~= 300MB
      initial: self 103564 children 154860
      grandchild alloc 300MB
      post_wait: self 103564 children 308720
      
      testcase5: zombie
        expect: pre_wait ~= initial, IOW the zombie process is not accounted.
                post_wait ~= 400MB, IOW wait() collect child's max_rss.
      initial: self 103564 children 308720
      child alloc 400MB
      pre_wait: self 103564 children 308720
      post_wait: self 103564 children 411312
      
      testcase6: SIG_IGN
        expect: initial ~= after_zombie (child's 500MB alloc should be ignored).
      initial: self 103564 children 411312
      child alloc 500MB
      after_zombie: self 103624 children 411312
      
      testcase7: exec (without fork)
        expect: initial ~= exec
      initial: self 103624 children 411312
      exec: self 103624 children 411312
      
      Linux result (actual test result)
      ========================================================
      allocate 100MB
      testcase1: fork inherit?
        expect: initial.self ~= child.self
      initial: self 102848 children 0
      fork child: self 102572 children 0
      
      testcase2: fork inherit? (cont.)
        expect: initial.children ~= 100MB, but child.children = 0
      initial: self 102876 children 102644
      child: self 102572 children 0
      
      testcase3: fork + malloc
        expect: child.self ~= initial.self + 50MB
      initial: self 102876 children 102644
      allocate +50MB
      fork child: self 153804 children 0
      
      testcase4: grandchild maxrss
        expect: post_wait.children ~= 300MB
      initial: self 102876 children 153864
      grandchild alloc 300MB
      post_wait: self 102876 children 307536
      
      testcase5: zombie
        expect: pre_wait ~= initial, IOW the zombie process is not accounted.
                post_wait ~= 400MB, IOW wait() collect child's max_rss.
      initial: self 102876 children 307536
      child alloc 400MB
      pre_wait: self 102876 children 307536
      post_wait: self 102876 children 410076
      
      testcase6: SIG_IGN
        expect: initial ~= after_zombie (child's 500MB alloc should be ignored).
      initial: self 102876 children 410076
      child alloc 500MB
      after_zombie: self 102880 children 410076
      
      testcase7: exec (without fork)
        expect: initial ~= exec
      initial: self 102880 children 410076
      exec: self 102880 children 410076
      Signed-off-by: NJiri Pirko <jpirko@redhat.com>
      Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1f10206c
  13. 21 9月, 2009 1 次提交
    • I
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      Ingo Molnar 提交于
      Bye-bye Performance Counters, welcome Performance Events!
      
      In the past few months the perfcounters subsystem has grown out its
      initial role of counting hardware events, and has become (and is
      becoming) a much broader generic event enumeration, reporting, logging,
      monitoring, analysis facility.
      
      Naming its core object 'perf_counter' and naming the subsystem
      'perfcounters' has become more and more of a misnomer. With pending
      code like hw-breakpoints support the 'counter' name is less and
      less appropriate.
      
      All in one, we've decided to rename the subsystem to 'performance
      events' and to propagate this rename through all fields, variables
      and API names. (in an ABI compatible fashion)
      
      The word 'event' is also a bit shorter than 'counter' - which makes
      it slightly more convenient to write/handle as well.
      
      Thanks goes to Stephane Eranian who first observed this misnomer and
      suggested a rename.
      
      User-space tooling and ABI compatibility is not affected - this patch
      should be function-invariant. (Also, defconfigs were not touched to
      keep the size down.)
      
      This patch has been generated via the following script:
      
        FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
      
        sed -i \
          -e 's/PERF_EVENT_/PERF_RECORD_/g' \
          -e 's/PERF_COUNTER/PERF_EVENT/g' \
          -e 's/perf_counter/perf_event/g' \
          -e 's/nb_counters/nb_events/g' \
          -e 's/swcounter/swevent/g' \
          -e 's/tpcounter_event/tp_event/g' \
          $FILES
      
        for N in $(find . -name perf_counter.[ch]); do
          M=$(echo $N | sed 's/perf_counter/perf_event/g')
          mv $N $M
        done
      
        FILES=$(find . -name perf_event.*)
      
        sed -i \
          -e 's/COUNTER_MASK/REG_MASK/g' \
          -e 's/COUNTER/EVENT/g' \
          -e 's/\<event\>/event_id/g' \
          -e 's/counter/event/g' \
          -e 's/Counter/Event/g' \
          $FILES
      
      ... to keep it as correct as possible. This script can also be
      used by anyone who has pending perfcounters patches - it converts
      a Linux kernel tree over to the new naming. We tried to time this
      change to the point in time where the amount of pending patches
      is the smallest: the end of the merge window.
      
      Namespace clashes were fixed up in a preparatory patch - and some
      stylistic fallout will be fixed up in a subsequent patch.
      
      ( NOTE: 'counters' are still the proper terminology when we deal
        with hardware registers - and these sed scripts are a bit
        over-eager in renaming them. I've undone some of that, but
        in case there's something left where 'counter' would be
        better than 'event' we can undo that on an individual basis
        instead of touching an otherwise nicely automated patch. )
      Suggested-by: NStephane Eranian <eranian@google.com>
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NPaul Mackerras <paulus@samba.org>
      Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: <linux-arch@vger.kernel.org>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      cdd6c482
  14. 16 9月, 2009 1 次提交
    • A
      HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process · 4db96cf0
      Andi Kleen 提交于
      This allows processes to override their early/late kill
      behaviour on hardware memory errors.
      
      Typically applications which are memory error aware is
      better of with early kill (see the error as soon
      as possible), all others with late kill (only
      see the error when the error is really impacting execution)
      
      There's a global sysctl, but this way an application
      can set its specific policy.
      
      We're using two bits, one to signify that the process
      stated its intention and that
      
      I also made the prctl future proof by enforcing
      the unused arguments are 0.
      
      The state is inherited to children.
      
      Note this makes us officially run out of process flags
      on 32bit, but the next patch can easily add another field.
      
      Manpage patch will be supplied separately.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      4db96cf0
  15. 17 6月, 2009 1 次提交
  16. 14 4月, 2009 1 次提交
  17. 03 4月, 2009 1 次提交
    • O
      pids: kill signal_struct-> __pgrp/__session and friends · 1b0f7ffd
      Oleg Nesterov 提交于
      We are wasting 2 words in signal_struct without any reason to implement
      task_pgrp_nr() and task_session_nr().
      
      task_session_nr() has no callers since
      2e2ba22e, we can remove it.
      
      task_pgrp_nr() is still (I believe wrongly) used in fs/autofsX and
      fs/coda.
      
      This patch reimplements task_pgrp_nr() via task_pgrp_nr_ns(), and kills
      __pgrp/__session and the related helpers.
      
      The change in drivers/char/tty_io.c is cosmetic, but hopefully makes sense
      anyway.
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Acked-by: Alan Cox <number6@the-village.bc.nu>		[tty parts]
      Cc: Cedric Le Goater <clg@fr.ibm.com>
      Cc: Dave Hansen <haveblue@us.ibm.com>
      Cc: Eric Biederman <ebiederm@xmission.com>
      Cc: Pavel Emelyanov <xemul@openvz.org>
      Cc: Serge Hallyn <serue@us.ibm.com>
      Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
      Cc: Roland McGrath <roland@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1b0f7ffd
  18. 01 4月, 2009 1 次提交
  19. 27 2月, 2009 1 次提交
  20. 06 2月, 2009 1 次提交
    • A
      revert "rlimit: permit setting RLIMIT_NOFILE to RLIM_INFINITY" · 60fd760f
      Andrew Morton 提交于
      Revert commit 0c2d64fb because it causes
      (arguably poorly designed) existing userspace to spend interminable
      periods closing billions of not-open file descriptors.
      
      We could bring this back, with some sort of opt-in tunable in /proc, which
      defaults to "off".
      
      Peter's alanysis follows:
      
      : I spent several hours trying to get to the bottom of a serious
      : performance issue that appeared on one of our servers after upgrading to
      : 2.6.28.  In the end it's what could be considered a userspace bug that
      : was triggered by a change in 2.6.28.  Since this might also affect other
      : people I figured I'd at least document what I found here, and maybe we
      : can even do something about it:
      :
      :
      : So, I upgraded some of debian.org's machines to 2.6.28.1 and immediately
      : the team maintaining our ftp archive complained that one of their
      : scripts that previously ran in a few minutes still hadn't even come
      : close to being done after an hour or so.  Downgrading to 2.6.27 fixed
      : that.
      :
      : Turns out that script is forking a lot and something in it or python or
      : whereever closes all the file descriptors it doesn't want to pass on.
      : That is, it starts at zero and goes up to ulimit -n/RLIMIT_NOFILE and
      : closes them all with a few exceptions.
      :
      : Turns out that takes a long time when your limit -n is now 2^20 (1048576).
      :
      : With 2.6.27.* the ulimit -n was the standard 1024, but with 2.6.28 it is
      : now a thousand times that.
      :
      : 2.6.28 included a patch titled "rlimit: permit setting RLIMIT_NOFILE to
      : RLIM_INFINITY" (0c2d64fb)[1] that
      : allows, as the title implies, to set the limit for number of files to
      : infinity.
      :
      : Closer investigation showed that the broken default ulimit did not apply
      : to "system" processes (like stuff started from init).  In the end I
      : could establish that all processes that passed through pam_limit at one
      : point had the bad resource limit.
      :
      : Apparently the pam library in Debian etch (4.0) initializes the limits
      : to some default values when it doesn't have any settings in limit.conf
      : to override them.  Turns out that for nofiles this is RLIM_INFINITY.
      : Commenting out "case RLIMIT_NOFILE" in pam_limit.c:267 of our pam
      : package version 0.79-5 fixes that - tho I'm not sure what side effects
      : that has.
      :
      : Debian lenny (the upcoming 5.0 version) doesn't have this issue as it
      : uses a different pam (version).
      Reported-by: NPeter Palfrader <weasel@debian.org>
      Cc: Adam Tkac <vonsch@gmail.com>
      Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
      Cc: <stable@kernel.org>		[2.6.28.x]
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      60fd760f
  21. 14 1月, 2009 9 次提交
  22. 07 1月, 2009 1 次提交
    • P
      Allow times and time system calls to return small negative values · e3d5a27d
      Paul Mackerras 提交于
      At the moment, the times() system call will appear to fail for a period
      shortly after boot, while the value it want to return is between -4095 and
      -1.  The same thing will also happen for the time() system call on 32-bit
      platforms some time in 2106 or so.
      
      On some platforms, such as x86, this is unavoidable because of the system
      call ABI, but other platforms such as powerpc have a separate error
      indication from the return value, so system calls can in fact return small
      negative values without indicating an error.  On those platforms,
      force_successful_syscall_return() provides a way to indicate that the
      system call return value should not be treated as an error even if it is
      in the range which would normally be taken as a negative error number.
      
      This adds a force_successful_syscall_return() call to the time() and
      times() system calls plus their 32-bit compat versions, so that they don't
      erroneously indicate an error on those platforms whose system call ABI has
      a separate error indication.  This will not affect anything on other
      platforms.
      
      Joakim Tjernlund added the fix for time() and the compat versions of
      time() and times(), after I did the fix for times().
      Signed-off-by: NJoakim Tjernlund <Joakim.Tjernlund@transmode.se>
      Signed-off-by: NPaul Mackerras <paulus@samba.org>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e3d5a27d
  23. 04 1月, 2009 1 次提交
  24. 11 12月, 2008 1 次提交
  25. 25 11月, 2008 1 次提交
    • S
      User namespaces: set of cleanups (v2) · 18b6e041
      Serge Hallyn 提交于
      The user_ns is moved from nsproxy to user_struct, so that a struct
      cred by itself is sufficient to determine access (which it otherwise
      would not be).  Corresponding ecryptfs fixes (by David Howells) are
      here as well.
      
      Fix refcounting.  The following rules now apply:
              1. The task pins the user struct.
              2. The user struct pins its user namespace.
              3. The user namespace pins the struct user which created it.
      
      User namespaces are cloned during copy_creds().  Unsharing a new user_ns
      is no longer possible.  (We could re-add that, but it'll cause code
      duplication and doesn't seem useful if PAM doesn't need to clone user
      namespaces).
      
      When a user namespace is created, its first user (uid 0) gets empty
      keyrings and a clean group_info.
      
      This incorporates a previous patch by David Howells.  Here
      is his original patch description:
      
      >I suggest adding the attached incremental patch.  It makes the following
      >changes:
      >
      > (1) Provides a current_user_ns() macro to wrap accesses to current's user
      >     namespace.
      >
      > (2) Fixes eCryptFS.
      >
      > (3) Renames create_new_userns() to create_user_ns() to be more consistent
      >     with the other associated functions and because the 'new' in the name is
      >     superfluous.
      >
      > (4) Moves the argument and permission checks made for CLONE_NEWUSER to the
      >     beginning of do_fork() so that they're done prior to making any attempts
      >     at allocation.
      >
      > (5) Calls create_user_ns() after prepare_creds(), and gives it the new creds
      >     to fill in rather than have it return the new root user.  I don't imagine
      >     the new root user being used for anything other than filling in a cred
      >     struct.
      >
      >     This also permits me to get rid of a get_uid() and a free_uid(), as the
      >     reference the creds were holding on the old user_struct can just be
      >     transferred to the new namespace's creator pointer.
      >
      > (6) Makes create_user_ns() reset the UIDs and GIDs of the creds under
      >     preparation rather than doing it in copy_creds().
      >
      >David
      
      >Signed-off-by: David Howells <dhowells@redhat.com>
      
      Changelog:
      	Oct 20: integrate dhowells comments
      		1. leave thread_keyring alone
      		2. use current_user_ns() in set_user()
      Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
      18b6e041
  26. 17 11月, 2008 1 次提交
  27. 14 11月, 2008 5 次提交
    • D
      CRED: Inaugurate COW credentials · d84f4f99
      David Howells 提交于
      Inaugurate copy-on-write credentials management.  This uses RCU to manage the
      credentials pointer in the task_struct with respect to accesses by other tasks.
      A process may only modify its own credentials, and so does not need locking to
      access or modify its own credentials.
      
      A mutex (cred_replace_mutex) is added to the task_struct to control the effect
      of PTRACE_ATTACHED on credential calculations, particularly with respect to
      execve().
      
      With this patch, the contents of an active credentials struct may not be
      changed directly; rather a new set of credentials must be prepared, modified
      and committed using something like the following sequence of events:
      
      	struct cred *new = prepare_creds();
      	int ret = blah(new);
      	if (ret < 0) {
      		abort_creds(new);
      		return ret;
      	}
      	return commit_creds(new);
      
      There are some exceptions to this rule: the keyrings pointed to by the active
      credentials may be instantiated - keyrings violate the COW rule as managing
      COW keyrings is tricky, given that it is possible for a task to directly alter
      the keys in a keyring in use by another task.
      
      To help enforce this, various pointers to sets of credentials, such as those in
      the task_struct, are declared const.  The purpose of this is compile-time
      discouragement of altering credentials through those pointers.  Once a set of
      credentials has been made public through one of these pointers, it may not be
      modified, except under special circumstances:
      
        (1) Its reference count may incremented and decremented.
      
        (2) The keyrings to which it points may be modified, but not replaced.
      
      The only safe way to modify anything else is to create a replacement and commit
      using the functions described in Documentation/credentials.txt (which will be
      added by a later patch).
      
      This patch and the preceding patches have been tested with the LTP SELinux
      testsuite.
      
      This patch makes several logical sets of alteration:
      
       (1) execve().
      
           This now prepares and commits credentials in various places in the
           security code rather than altering the current creds directly.
      
       (2) Temporary credential overrides.
      
           do_coredump() and sys_faccessat() now prepare their own credentials and
           temporarily override the ones currently on the acting thread, whilst
           preventing interference from other threads by holding cred_replace_mutex
           on the thread being dumped.
      
           This will be replaced in a future patch by something that hands down the
           credentials directly to the functions being called, rather than altering
           the task's objective credentials.
      
       (3) LSM interface.
      
           A number of functions have been changed, added or removed:
      
           (*) security_capset_check(), ->capset_check()
           (*) security_capset_set(), ->capset_set()
      
           	 Removed in favour of security_capset().
      
           (*) security_capset(), ->capset()
      
           	 New.  This is passed a pointer to the new creds, a pointer to the old
           	 creds and the proposed capability sets.  It should fill in the new
           	 creds or return an error.  All pointers, barring the pointer to the
           	 new creds, are now const.
      
           (*) security_bprm_apply_creds(), ->bprm_apply_creds()
      
           	 Changed; now returns a value, which will cause the process to be
           	 killed if it's an error.
      
           (*) security_task_alloc(), ->task_alloc_security()
      
           	 Removed in favour of security_prepare_creds().
      
           (*) security_cred_free(), ->cred_free()
      
           	 New.  Free security data attached to cred->security.
      
           (*) security_prepare_creds(), ->cred_prepare()
      
           	 New. Duplicate any security data attached to cred->security.
      
           (*) security_commit_creds(), ->cred_commit()
      
           	 New. Apply any security effects for the upcoming installation of new
           	 security by commit_creds().
      
           (*) security_task_post_setuid(), ->task_post_setuid()
      
           	 Removed in favour of security_task_fix_setuid().
      
           (*) security_task_fix_setuid(), ->task_fix_setuid()
      
           	 Fix up the proposed new credentials for setuid().  This is used by
           	 cap_set_fix_setuid() to implicitly adjust capabilities in line with
           	 setuid() changes.  Changes are made to the new credentials, rather
           	 than the task itself as in security_task_post_setuid().
      
           (*) security_task_reparent_to_init(), ->task_reparent_to_init()
      
           	 Removed.  Instead the task being reparented to init is referred
           	 directly to init's credentials.
      
      	 NOTE!  This results in the loss of some state: SELinux's osid no
      	 longer records the sid of the thread that forked it.
      
           (*) security_key_alloc(), ->key_alloc()
           (*) security_key_permission(), ->key_permission()
      
           	 Changed.  These now take cred pointers rather than task pointers to
           	 refer to the security context.
      
       (4) sys_capset().
      
           This has been simplified and uses less locking.  The LSM functions it
           calls have been merged.
      
       (5) reparent_to_kthreadd().
      
           This gives the current thread the same credentials as init by simply using
           commit_thread() to point that way.
      
       (6) __sigqueue_alloc() and switch_uid()
      
           __sigqueue_alloc() can't stop the target task from changing its creds
           beneath it, so this function gets a reference to the currently applicable
           user_struct which it then passes into the sigqueue struct it returns if
           successful.
      
           switch_uid() is now called from commit_creds(), and possibly should be
           folded into that.  commit_creds() should take care of protecting
           __sigqueue_alloc().
      
       (7) [sg]et[ug]id() and co and [sg]et_current_groups.
      
           The set functions now all use prepare_creds(), commit_creds() and
           abort_creds() to build and check a new set of credentials before applying
           it.
      
           security_task_set[ug]id() is called inside the prepared section.  This
           guarantees that nothing else will affect the creds until we've finished.
      
           The calling of set_dumpable() has been moved into commit_creds().
      
           Much of the functionality of set_user() has been moved into
           commit_creds().
      
           The get functions all simply access the data directly.
      
       (8) security_task_prctl() and cap_task_prctl().
      
           security_task_prctl() has been modified to return -ENOSYS if it doesn't
           want to handle a function, or otherwise return the return value directly
           rather than through an argument.
      
           Additionally, cap_task_prctl() now prepares a new set of credentials, even
           if it doesn't end up using it.
      
       (9) Keyrings.
      
           A number of changes have been made to the keyrings code:
      
           (a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have
           	 all been dropped and built in to the credentials functions directly.
           	 They may want separating out again later.
      
           (b) key_alloc() and search_process_keyrings() now take a cred pointer
           	 rather than a task pointer to specify the security context.
      
           (c) copy_creds() gives a new thread within the same thread group a new
           	 thread keyring if its parent had one, otherwise it discards the thread
           	 keyring.
      
           (d) The authorisation key now points directly to the credentials to extend
           	 the search into rather pointing to the task that carries them.
      
           (e) Installing thread, process or session keyrings causes a new set of
           	 credentials to be created, even though it's not strictly necessary for
           	 process or session keyrings (they're shared).
      
      (10) Usermode helper.
      
           The usermode helper code now carries a cred struct pointer in its
           subprocess_info struct instead of a new session keyring pointer.  This set
           of credentials is derived from init_cred and installed on the new process
           after it has been cloned.
      
           call_usermodehelper_setup() allocates the new credentials and
           call_usermodehelper_freeinfo() discards them if they haven't been used.  A
           special cred function (prepare_usermodeinfo_creds()) is provided
           specifically for call_usermodehelper_setup() to call.
      
           call_usermodehelper_setkeys() adjusts the credentials to sport the
           supplied keyring as the new session keyring.
      
      (11) SELinux.
      
           SELinux has a number of changes, in addition to those to support the LSM
           interface changes mentioned above:
      
           (a) selinux_setprocattr() no longer does its check for whether the
           	 current ptracer can access processes with the new SID inside the lock
           	 that covers getting the ptracer's SID.  Whilst this lock ensures that
           	 the check is done with the ptracer pinned, the result is only valid
           	 until the lock is released, so there's no point doing it inside the
           	 lock.
      
      (12) is_single_threaded().
      
           This function has been extracted from selinux_setprocattr() and put into
           a file of its own in the lib/ directory as join_session_keyring() now
           wants to use it too.
      
           The code in SELinux just checked to see whether a task shared mm_structs
           with other tasks (CLONE_VM), but that isn't good enough.  We really want
           to know if they're part of the same thread group (CLONE_THREAD).
      
      (13) nfsd.
      
           The NFS server daemon now has to use the COW credentials to set the
           credentials it is going to use.  It really needs to pass the credentials
           down to the functions it calls, but it can't do that until other patches
           in this series have been applied.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      d84f4f99
    • D
      CRED: Use RCU to access another task's creds and to release a task's own creds · c69e8d9c
      David Howells 提交于
      Use RCU to access another task's creds and to release a task's own creds.
      This means that it will be possible for the credentials of a task to be
      replaced without another task (a) requiring a full lock to read them, and (b)
      seeing deallocated memory.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      c69e8d9c
    • D
      CRED: Wrap current->cred and a few other accessors · 86a264ab
      David Howells 提交于
      Wrap current->cred and a few other accessors to hide their actual
      implementation.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      86a264ab
    • D
      CRED: Separate task security context from task_struct · b6dff3ec
      David Howells 提交于
      Separate the task security context from task_struct.  At this point, the
      security data is temporarily embedded in the task_struct with two pointers
      pointing to it.
      
      Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
      entry.S via asm-offsets.
      
      With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      b6dff3ec
    • D
      CRED: Wrap task credential accesses in the core kernel · 76aac0e9
      David Howells 提交于
      Wrap access to task credentials so that they can be separated more easily from
      the task_struct during the introduction of COW creds.
      
      Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
      
      Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
      sense to use RCU directly rather than a convenient wrapper; these will be
      addressed by later patches.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: linux-audit@redhat.com
      Cc: containers@lists.linux-foundation.org
      Cc: linux-mm@kvack.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      76aac0e9