Magellan Linux

  • Back to homepage
    • /[pkg-src]/trunk/kernel26-magellan/patches-2.6.21-r13/0002-2.6.21-sched-sd-0.48-interactive_tunable.patch

    Contents of /trunk/kernel26-magellan/patches-2.6.21-r13/0002-2.6.21-sched-sd-0.48-interactive_tunable.patch

    Parent Directory Parent Directory | Revision Log Revision Log

    Revision 319 - (show annotations) (download)
    Sun Aug 19 18:14:21 2007 UTC (17 years, 2 months ago) by niro
    File size: 4860 byte(s) 
    -2.6.21-magellan-r13
    1 Add "interactive" tunable and enable by default.
    2
    3 The staircase-deadline cpu scheduler can be set in either purely
    4 forward-looking mode for absolutely rigid fairness and cpu distribution
    5 according to nice level, or it can allow a small per-process history
    6 to smooth out cpu usage perturbations common in interactive tasks by
    7 enabling this sysctl. While small fairness issues can arise with this
    8 enabled, overall fairness is usually still strongly maintained and
    9 starvation is never possible. Enabling this can significantly smooth
    10 out 3d graphics and games.
    11
    12 Signed-off-by: Con Kolivas <kernel@kolivas.org>
    13
    14 ---
    15 Documentation/sysctl/kernel.txt | 16 ++++++++++++++++
    16 kernel/sched.c | 17 +++++++++++++++--
    17 kernel/sysctl.c | 9 +++++++++
    18 3 files changed, 40 insertions(+), 2 deletions(-)
    19
    20 Index: linux-2.6.21-ck2/kernel/sched.c
    21 ===================================================================
    22 --- linux-2.6.21-ck2.orig/kernel/sched.c 2007-05-14 19:30:30.000000000 +1000
    23 +++ linux-2.6.21-ck2/kernel/sched.c 2007-05-14 19:30:30.000000000 +1000
    24 @@ -101,6 +101,7 @@ unsigned long long __attribute__((weak))
    25 * Tunable via /proc interface.
    26 */
    27 int rr_interval __read_mostly = 8;
    28 +int sched_interactive __read_mostly = 1;
    29
    30 /*
    31 * This contains a bitmap for each dynamic priority level with empty slots
    32 @@ -687,6 +688,18 @@ static int first_prio_slot(struct task_s
    33 }
    34
    35 /*
    36 + * In sched_interactive mode priority allocation occurs per process per rq
    37 + * array swap. In !sched_interactive mode all waking tasks must obey the
    38 + * current prio level of all other tasks running per array swap.
    39 + */
    40 +static int minprio(struct rq *rq, int uprio)
    41 +{
    42 + if (sched_interactive)
    43 + return MAX_RT_PRIO;
    44 + return rq->prio_level[uprio];
    45 +}
    46 +
    47 +/*
    48 * Find the first unused slot by this task that is also in its prio_matrix
    49 * level. SCHED_BATCH tasks do not use the priority matrix. They only take
    50 * priority slots from their static_prio and above.
    51 @@ -714,11 +727,11 @@ static int next_entitled_slot(struct tas
    52 if (likely(p->policy != SCHED_BATCH))
    53 array->best_static_prio = p->static_prio;
    54 } else if (p->static_prio == array->best_static_prio) {
    55 - search_prio = rq->prio_level[uprio];
    56 + search_prio = minprio(rq, uprio);
    57 } else {
    58 int i;
    59
    60 - search_prio = rq->prio_level[uprio];
    61 + search_prio = minprio(rq, uprio);
    62 /* A bound O(n) function, worst case n is 40 */
    63 for (i = array->best_static_prio; i <= p->static_prio ; i++) {
    64 if (!rq->prio_level[USER_PRIO(i)])
    65 Index: linux-2.6.21-ck2/kernel/sysctl.c
    66 ===================================================================
    67 --- linux-2.6.21-ck2.orig/kernel/sysctl.c 2007-05-14 19:30:30.000000000 +1000
    68 +++ linux-2.6.21-ck2/kernel/sysctl.c 2007-05-14 19:30:30.000000000 +1000
    69 @@ -77,6 +77,7 @@ extern int sysctl_drop_caches;
    70 extern int percpu_pagelist_fraction;
    71 extern int compat_log;
    72 extern int rr_interval;
    73 +extern int sched_interactive;
    74
    75 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
    76 static int maxolduid = 65535;
    77 @@ -519,6 +520,14 @@ static ctl_table kern_table[] = {
    78 .extra1 = &one,
    79 .extra2 = &five_thousand,
    80 },
    81 + {
    82 + .ctl_name = CTL_UNNUMBERED,
    83 + .procname = "interactive",
    84 + .data = &sched_interactive,
    85 + .maxlen = sizeof(int),
    86 + .mode = 0644,
    87 + .proc_handler = &proc_dointvec,
    88 + },
    89 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
    90 {
    91 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
    92 Index: linux-2.6.21-ck2/Documentation/sysctl/kernel.txt
    93 ===================================================================
    94 --- linux-2.6.21-ck2.orig/Documentation/sysctl/kernel.txt 2007-05-14 19:30:30.000000000 +1000
    95 +++ linux-2.6.21-ck2/Documentation/sysctl/kernel.txt 2007-05-14 19:30:30.000000000 +1000
    96 @@ -25,6 +25,7 @@ show up in /proc/sys/kernel:
    97 - domainname
    98 - hostname
    99 - hotplug
    100 +- interactive
    101 - java-appletviewer [ binfmt_java, obsolete ]
    102 - java-interpreter [ binfmt_java, obsolete ]
    103 - kstack_depth_to_print [ X86 only ]
    104 @@ -165,6 +166,21 @@ Default value is "/sbin/hotplug".
    105
    106 ==============================================================
    107
    108 +interactive:
    109 +
    110 +The staircase-deadline cpu scheduler can be set in either purely
    111 +forward-looking mode for absolutely rigid fairness and cpu distribution
    112 +according to nice level, or it can allow a small per-process history
    113 +to smooth out cpu usage perturbations common in interactive tasks by
    114 +enabling this sysctl. While small fairness issues can arise with this
    115 +enabled, overall fairness is usually still strongly maintained and
    116 +starvation is never possible. Enabling this can significantly smooth
    117 +out 3d graphics and games.
    118 +
    119 +Default value is 1 (enabled).
    120 +
    121 +==============================================================
    122 +
    123 l2cr: (PPC only)
    124
    125 This flag controls the L2 cache of G3 processor boards. If