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Diffstat (limited to 'manual/resource.texi')
| -rw-r--r-- | manual/resource.texi | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/manual/resource.texi b/manual/resource.texi index 5a1bb040be..b5f0c24873 100644 --- a/manual/resource.texi +++ b/manual/resource.texi @@ -25,6 +25,8 @@ in @file{sys/resource.h}. @comment sys/resource.h @comment BSD @deftypefun int getrusage (int @var{processes}, struct rusage *@var{rusage}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c On HURD, this calls task_info 3 times. On UNIX, it's a syscall. This function reports resource usage totals for processes specified by @var{processes}, storing the information in @code{*@var{rusage}}. @@ -132,6 +134,8 @@ scheduled). @comment sys/vtimes.h @deftypefun int vtimes (struct vtimes *@var{current}, struct vtimes *@var{child}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Calls getrusage twice. @code{vtimes} reports resource usage totals for a process. @@ -223,6 +227,8 @@ The symbols for use with @code{getrlimit}, @code{setrlimit}, @comment sys/resource.h @comment BSD @deftypefun int getrlimit (int @var{resource}, struct rlimit *@var{rlp}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on most systems. Read the current and maximum limits for the resource @var{resource} and store them in @code{*@var{rlp}}. @@ -237,6 +243,8 @@ LFS interface transparently replaces the old interface. @comment sys/resource.h @comment Unix98 @deftypefun int getrlimit64 (int @var{resource}, struct rlimit64 *@var{rlp}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on most systems, wrapper to getrlimit otherwise. This function is similar to @code{getrlimit} but its second parameter is a pointer to a variable of type @code{struct rlimit64}, which allows it to read values which wouldn't fit in the member of a @code{struct @@ -250,6 +258,8 @@ If the sources are compiled with @code{_FILE_OFFSET_BITS == 64} on a @comment sys/resource.h @comment BSD @deftypefun int setrlimit (int @var{resource}, const struct rlimit *@var{rlp}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on most systems; lock-taking critical section on HURD. Store the current and maximum limits for the resource @var{resource} in @code{*@var{rlp}}. @@ -275,6 +285,8 @@ LFS interface transparently replaces the old interface. @comment sys/resource.h @comment Unix98 @deftypefun int setrlimit64 (int @var{resource}, const struct rlimit64 *@var{rlp}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Wrapper for setrlimit or direct syscall. This function is similar to @code{setrlimit} but its second parameter is a pointer to a variable of type @code{struct rlimit64} which allows it to set values which wouldn't fit in the member of a @code{struct @@ -434,6 +446,9 @@ above do. The functions above are better choices. @comment ulimit.h @comment BSD @deftypefun {long int} ulimit (int @var{cmd}, @dots{}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Wrapper for getrlimit, setrlimit or +@c sysconf(_SC_OPEN_MAX)->getdtablesize->getrlimit. @code{ulimit} gets the current limit or sets the current and maximum limit for a particular resource for the calling process according to the @@ -480,6 +495,10 @@ A process tried to increase a maximum limit, but is not superuser. @comment sys/vlimit.h @comment BSD @deftypefun int vlimit (int @var{resource}, int @var{limit}) +@safety{@prelim{}@mtunsafe{@mtasurace{:setrlimit}}@asunsafe{}@acsafe{}} +@c It calls getrlimit and modifies the rlim_cur field before calling +@c setrlimit. There's a window for a concurrent call to setrlimit that +@c modifies e.g. rlim_max, which will be lost if running as super-user. @code{vlimit} sets the current limit for a resource for a process. @@ -778,6 +797,8 @@ absolute priority value @comment sched.h @comment POSIX @deftypefun int sched_setscheduler (pid_t @var{pid}, int @var{policy}, const struct sched_param *@var{param}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function sets both the absolute priority and the scheduling policy for a process. @@ -848,6 +869,8 @@ tell you what the valid range is. @comment sched.h @comment POSIX @deftypefun int sched_getscheduler (pid_t @var{pid}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function returns the scheduling policy assigned to the process with Process ID (pid) @var{pid}, or the calling process if @var{pid} is zero. @@ -881,6 +904,8 @@ absolute priority, use @code{sched_getparam}. @comment sched.h @comment POSIX @deftypefun int sched_setparam (pid_t @var{pid}, const struct sched_param *@var{param}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function sets a process' absolute priority. @@ -894,6 +919,8 @@ It is functionally identical to @code{sched_setscheduler} with @comment sched.h @comment POSIX @deftypefun int sched_getparam (pid_t @var{pid}, struct sched_param *@var{param}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function returns a process' absolute priority. @@ -923,6 +950,8 @@ There is no process with pid @var{pid} and it is not zero. @comment sched.h @comment POSIX @deftypefun int sched_get_priority_min (int @var{policy}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function returns the lowest absolute priority value that is allowable for a process with scheduling policy @var{policy}. @@ -943,6 +972,8 @@ to this function are: @comment sched.h @comment POSIX @deftypefun int sched_get_priority_max (int @var{policy}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function returns the highest absolute priority value that is allowable for a process that with scheduling policy @var{policy}. @@ -963,6 +994,8 @@ to this function are: @comment sched.h @comment POSIX @deftypefun int sched_rr_get_interval (pid_t @var{pid}, struct timespec *@var{interval}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall, Linux only. This function returns the length of the quantum (time slice) used with the Round Robin scheduling policy, if it is used, for the process with @@ -987,6 +1020,8 @@ function, so there are no specific @code{errno} values. @comment sched.h @comment POSIX @deftypefun int sched_yield (void) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on Linux; alias to swtch on HURD. This function voluntarily gives up the process' claim on the CPU. @@ -1138,6 +1173,8 @@ The highest valid nice value. @comment sys/resource.h @comment BSD,POSIX @deftypefun int getpriority (int @var{class}, int @var{id}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on UNIX. On HURD, calls _hurd_priority_which_map. Return the nice value of a set of processes; @var{class} and @var{id} specify which ones (see below). If the processes specified do not all have the same nice value, this returns the lowest value that any of them @@ -1165,6 +1202,8 @@ afterward as the criterion for failure. @comment sys/resource.h @comment BSD,POSIX @deftypefun int setpriority (int @var{class}, int @var{id}, int @var{niceval}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Direct syscall on UNIX. On HURD, calls _hurd_priority_which_map. Set the nice value of a set of processes to @var{niceval}; @var{class} and @var{id} specify which ones (see below). @@ -1222,6 +1261,11 @@ process group, or its owner (real uid), according to @var{class}. @comment unistd.h @comment BSD @deftypefun int nice (int @var{increment}) +@safety{@prelim{}@mtunsafe{@mtasurace{:setpriority}}@asunsafe{}@acsafe{}} +@c Calls getpriority before and after setpriority, using the result of +@c the first call to compute the argument for setpriority. This creates +@c a window for a concurrent setpriority (or nice) call to be lost or +@c exhibit surprising behavior. Increment the nice value of the calling process by @var{increment}. The return value is the new nice value on success, and @code{-1} on failure. In the case of failure, @code{errno} will be set to the @@ -1319,6 +1363,10 @@ manipulation should happen via the next four macros. @comment sched.h @comment GNU @deftypefn Macro void CPU_ZERO (cpu_set_t *@var{set}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c CPU_ZERO ok +@c __CPU_ZERO_S ok +@c memset dup ok This macro initializes the CPU set @var{set} to be the empty set. This macro is a GNU extension and is defined in @file{sched.h}. @@ -1327,6 +1375,11 @@ This macro is a GNU extension and is defined in @file{sched.h}. @comment sched.h @comment GNU @deftypefn Macro void CPU_SET (int @var{cpu}, cpu_set_t *@var{set}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c CPU_SET ok +@c __CPU_SET_S ok +@c __CPUELT ok +@c __CPUMASK ok This macro adds @var{cpu} to the CPU set @var{set}. The @var{cpu} parameter must not have side effects since it is @@ -1338,6 +1391,11 @@ This macro is a GNU extension and is defined in @file{sched.h}. @comment sched.h @comment GNU @deftypefn Macro void CPU_CLR (int @var{cpu}, cpu_set_t *@var{set}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c CPU_CLR ok +@c __CPU_CLR_S ok +@c __CPUELT dup ok +@c __CPUMASK dup ok This macro removes @var{cpu} from the CPU set @var{set}. The @var{cpu} parameter must not have side effects since it is @@ -1349,6 +1407,11 @@ This macro is a GNU extension and is defined in @file{sched.h}. @comment sched.h @comment GNU @deftypefn Macro int CPU_ISSET (int @var{cpu}, const cpu_set_t *@var{set}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c CPU_ISSET ok +@c __CPU_ISSET_S ok +@c __CPUELT dup ok +@c __CPUMASK dup ok This macro returns a nonzero value (true) if @var{cpu} is a member of the CPU set @var{set}, and zero (false) otherwise. @@ -1365,6 +1428,9 @@ affinity mask can be retrieved from the system. @comment sched.h @comment GNU @deftypefun int sched_getaffinity (pid_t @var{pid}, size_t @var{cpusetsize}, cpu_set_t *@var{cpuset}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Wrapped syscall to zero out past the kernel cpu set size; Linux +@c only. This functions stores the CPU affinity mask for the process or thread with the ID @var{pid} in the @var{cpusetsize} bytes long bitmap @@ -1393,6 +1459,9 @@ interface must be provided for that. @comment sched.h @comment GNU @deftypefun int sched_setaffinity (pid_t @var{pid}, size_t @var{cpusetsize}, const cpu_set_t *@var{cpuset}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Wrapped syscall to detect attempts to set bits past the kernel cpu +@c set size; Linux only. This function installs the @var{cpusetsize} bytes long affinity mask pointed to by @var{cpuset} for the process or thread with the ID @var{pid}. @@ -1516,6 +1585,9 @@ There is a much older interface available, too. @comment unistd.h @comment BSD @deftypefun int getpagesize (void) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +@c Obtained from the aux vec at program startup time. GNU/Linux/m68k is +@c the exception, with the possibility of a syscall. The @code{getpagesize} function returns the page size of the process. This value is fixed for the runtime of the process but can vary in different runs of the application. @@ -1559,6 +1631,8 @@ get this information two functions. They are declared in the file @comment sys/sysinfo.h @comment GNU @deftypefun {long int} get_phys_pages (void) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuheap{} @asulock{}}@acunsafe{@aculock{} @acsfd{} @acsmem{}}} +@c This fopens a /proc file and scans it for the requested information. The @code{get_phys_pages} function returns the total number of pages of physical the system has. To get the amount of memory this number has to be multiplied by the page size. @@ -1569,6 +1643,7 @@ This function is a GNU extension. @comment sys/sysinfo.h @comment GNU @deftypefun {long int} get_avphys_pages (void) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuheap{} @asulock{}}@acunsafe{@aculock{} @acsfd{} @acsmem{}}} The @code{get_phys_pages} function returns the number of available pages of physical the system has. To get the amount of memory this number has to be multiplied by the page size. @@ -1614,6 +1689,9 @@ in @file{sys/sysinfo.h}. @comment sys/sysinfo.h @comment GNU @deftypefun int get_nprocs_conf (void) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuheap{} @asulock{}}@acunsafe{@aculock{} @acsfd{} @acsmem{}}} +@c This function reads from from /sys using dir streams (single user, so +@c no @mtasurace issue), and on some arches, from /proc using streams. The @code{get_nprocs_conf} function returns the number of processors the operating system configured. @@ -1623,6 +1701,8 @@ This function is a GNU extension. @comment sys/sysinfo.h @comment GNU @deftypefun int get_nprocs (void) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}} +@c This function reads from /proc using file descriptor I/O. The @code{get_nprocs} function returns the number of available processors. This function is a GNU extension. @@ -1638,6 +1718,10 @@ running. This number is average over different periods of times @comment stdlib.h @comment BSD @deftypefun int getloadavg (double @var{loadavg}[], int @var{nelem}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}} +@c Calls host_info on HURD; on Linux, opens /proc/loadavg, reads from +@c it, closes it, without cancellation point, and calls strtod_l with +@c the C locale to convert the strings to doubles. This function gets the 1, 5 and 15 minute load averages of the system. The values are placed in @var{loadavg}. @code{getloadavg} will place at most @var{nelem} elements into the array but never more than |