diff options
author | Ingo Molnar <mingo@kernel.org> | 2016-03-15 04:00:12 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-03-15 04:01:06 -0400 |
commit | 8bc6782fe20bd2584c73a35c47329c9fd0a8d34c (patch) | |
tree | c7fc6f467ee212e4ef442e70843c48fcf3c67c17 /kernel/rcu/tree.c | |
parent | e23604edac2a7be6a8808a5d13fac6b9df4eb9a8 (diff) | |
parent | 3500efae4410454522697c94c23fc40323c0cee9 (diff) |
Merge commit 'fixes.2015.02.23a' into core/rcu
Conflicts:
kernel/rcu/tree.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/rcu/tree.c')
-rw-r--r-- | kernel/rcu/tree.c | 143 |
1 files changed, 70 insertions, 73 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 9fd5b628a88d..55cea189783f 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c | |||
@@ -108,7 +108,6 @@ RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched); | |||
108 | RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh); | 108 | RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh); |
109 | 109 | ||
110 | static struct rcu_state *const rcu_state_p; | 110 | static struct rcu_state *const rcu_state_p; |
111 | static struct rcu_data __percpu *const rcu_data_p; | ||
112 | LIST_HEAD(rcu_struct_flavors); | 111 | LIST_HEAD(rcu_struct_flavors); |
113 | 112 | ||
114 | /* Dump rcu_node combining tree at boot to verify correct setup. */ | 113 | /* Dump rcu_node combining tree at boot to verify correct setup. */ |
@@ -1083,13 +1082,12 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp, | |||
1083 | rcu_sysidle_check_cpu(rdp, isidle, maxj); | 1082 | rcu_sysidle_check_cpu(rdp, isidle, maxj); |
1084 | if ((rdp->dynticks_snap & 0x1) == 0) { | 1083 | if ((rdp->dynticks_snap & 0x1) == 0) { |
1085 | trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, TPS("dti")); | 1084 | trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, TPS("dti")); |
1086 | return 1; | ||
1087 | } else { | ||
1088 | if (ULONG_CMP_LT(READ_ONCE(rdp->gpnum) + ULONG_MAX / 4, | 1085 | if (ULONG_CMP_LT(READ_ONCE(rdp->gpnum) + ULONG_MAX / 4, |
1089 | rdp->mynode->gpnum)) | 1086 | rdp->mynode->gpnum)) |
1090 | WRITE_ONCE(rdp->gpwrap, true); | 1087 | WRITE_ONCE(rdp->gpwrap, true); |
1091 | return 0; | 1088 | return 1; |
1092 | } | 1089 | } |
1090 | return 0; | ||
1093 | } | 1091 | } |
1094 | 1092 | ||
1095 | /* | 1093 | /* |
@@ -1173,15 +1171,16 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp, | |||
1173 | smp_mb(); /* ->cond_resched_completed before *rcrmp. */ | 1171 | smp_mb(); /* ->cond_resched_completed before *rcrmp. */ |
1174 | WRITE_ONCE(*rcrmp, | 1172 | WRITE_ONCE(*rcrmp, |
1175 | READ_ONCE(*rcrmp) + rdp->rsp->flavor_mask); | 1173 | READ_ONCE(*rcrmp) + rdp->rsp->flavor_mask); |
1176 | resched_cpu(rdp->cpu); /* Force CPU into scheduler. */ | ||
1177 | rdp->rsp->jiffies_resched += 5; /* Enable beating. */ | ||
1178 | } else if (ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) { | ||
1179 | /* Time to beat on that CPU again! */ | ||
1180 | resched_cpu(rdp->cpu); /* Force CPU into scheduler. */ | ||
1181 | rdp->rsp->jiffies_resched += 5; /* Re-enable beating. */ | ||
1182 | } | 1174 | } |
1175 | rdp->rsp->jiffies_resched += 5; /* Re-enable beating. */ | ||
1183 | } | 1176 | } |
1184 | 1177 | ||
1178 | /* And if it has been a really long time, kick the CPU as well. */ | ||
1179 | if (ULONG_CMP_GE(jiffies, | ||
1180 | rdp->rsp->gp_start + 2 * jiffies_till_sched_qs) || | ||
1181 | ULONG_CMP_GE(jiffies, rdp->rsp->gp_start + jiffies_till_sched_qs)) | ||
1182 | resched_cpu(rdp->cpu); /* Force CPU into scheduler. */ | ||
1183 | |||
1185 | return 0; | 1184 | return 0; |
1186 | } | 1185 | } |
1187 | 1186 | ||
@@ -1246,7 +1245,7 @@ static void rcu_dump_cpu_stacks(struct rcu_state *rsp) | |||
1246 | if (rnp->qsmask & (1UL << cpu)) | 1245 | if (rnp->qsmask & (1UL << cpu)) |
1247 | dump_cpu_task(rnp->grplo + cpu); | 1246 | dump_cpu_task(rnp->grplo + cpu); |
1248 | } | 1247 | } |
1249 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1248 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1250 | } | 1249 | } |
1251 | } | 1250 | } |
1252 | 1251 | ||
@@ -1266,12 +1265,12 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum) | |||
1266 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 1265 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
1267 | delta = jiffies - READ_ONCE(rsp->jiffies_stall); | 1266 | delta = jiffies - READ_ONCE(rsp->jiffies_stall); |
1268 | if (delta < RCU_STALL_RAT_DELAY || !rcu_gp_in_progress(rsp)) { | 1267 | if (delta < RCU_STALL_RAT_DELAY || !rcu_gp_in_progress(rsp)) { |
1269 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1268 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1270 | return; | 1269 | return; |
1271 | } | 1270 | } |
1272 | WRITE_ONCE(rsp->jiffies_stall, | 1271 | WRITE_ONCE(rsp->jiffies_stall, |
1273 | jiffies + 3 * rcu_jiffies_till_stall_check() + 3); | 1272 | jiffies + 3 * rcu_jiffies_till_stall_check() + 3); |
1274 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1273 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1275 | 1274 | ||
1276 | /* | 1275 | /* |
1277 | * OK, time to rat on our buddy... | 1276 | * OK, time to rat on our buddy... |
@@ -1292,7 +1291,7 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum) | |||
1292 | ndetected++; | 1291 | ndetected++; |
1293 | } | 1292 | } |
1294 | } | 1293 | } |
1295 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1294 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1296 | } | 1295 | } |
1297 | 1296 | ||
1298 | print_cpu_stall_info_end(); | 1297 | print_cpu_stall_info_end(); |
@@ -1357,7 +1356,7 @@ static void print_cpu_stall(struct rcu_state *rsp) | |||
1357 | if (ULONG_CMP_GE(jiffies, READ_ONCE(rsp->jiffies_stall))) | 1356 | if (ULONG_CMP_GE(jiffies, READ_ONCE(rsp->jiffies_stall))) |
1358 | WRITE_ONCE(rsp->jiffies_stall, | 1357 | WRITE_ONCE(rsp->jiffies_stall, |
1359 | jiffies + 3 * rcu_jiffies_till_stall_check() + 3); | 1358 | jiffies + 3 * rcu_jiffies_till_stall_check() + 3); |
1360 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1359 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1361 | 1360 | ||
1362 | /* | 1361 | /* |
1363 | * Attempt to revive the RCU machinery by forcing a context switch. | 1362 | * Attempt to revive the RCU machinery by forcing a context switch. |
@@ -1595,7 +1594,7 @@ rcu_start_future_gp(struct rcu_node *rnp, struct rcu_data *rdp, | |||
1595 | } | 1594 | } |
1596 | unlock_out: | 1595 | unlock_out: |
1597 | if (rnp != rnp_root) | 1596 | if (rnp != rnp_root) |
1598 | raw_spin_unlock(&rnp_root->lock); | 1597 | raw_spin_unlock_rcu_node(rnp_root); |
1599 | out: | 1598 | out: |
1600 | if (c_out != NULL) | 1599 | if (c_out != NULL) |
1601 | *c_out = c; | 1600 | *c_out = c; |
@@ -1814,7 +1813,7 @@ static void note_gp_changes(struct rcu_state *rsp, struct rcu_data *rdp) | |||
1814 | return; | 1813 | return; |
1815 | } | 1814 | } |
1816 | needwake = __note_gp_changes(rsp, rnp, rdp); | 1815 | needwake = __note_gp_changes(rsp, rnp, rdp); |
1817 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 1816 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
1818 | if (needwake) | 1817 | if (needwake) |
1819 | rcu_gp_kthread_wake(rsp); | 1818 | rcu_gp_kthread_wake(rsp); |
1820 | } | 1819 | } |
@@ -1839,7 +1838,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1839 | raw_spin_lock_irq_rcu_node(rnp); | 1838 | raw_spin_lock_irq_rcu_node(rnp); |
1840 | if (!READ_ONCE(rsp->gp_flags)) { | 1839 | if (!READ_ONCE(rsp->gp_flags)) { |
1841 | /* Spurious wakeup, tell caller to go back to sleep. */ | 1840 | /* Spurious wakeup, tell caller to go back to sleep. */ |
1842 | raw_spin_unlock_irq(&rnp->lock); | 1841 | raw_spin_unlock_irq_rcu_node(rnp); |
1843 | return false; | 1842 | return false; |
1844 | } | 1843 | } |
1845 | WRITE_ONCE(rsp->gp_flags, 0); /* Clear all flags: New grace period. */ | 1844 | WRITE_ONCE(rsp->gp_flags, 0); /* Clear all flags: New grace period. */ |
@@ -1849,7 +1848,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1849 | * Grace period already in progress, don't start another. | 1848 | * Grace period already in progress, don't start another. |
1850 | * Not supposed to be able to happen. | 1849 | * Not supposed to be able to happen. |
1851 | */ | 1850 | */ |
1852 | raw_spin_unlock_irq(&rnp->lock); | 1851 | raw_spin_unlock_irq_rcu_node(rnp); |
1853 | return false; | 1852 | return false; |
1854 | } | 1853 | } |
1855 | 1854 | ||
@@ -1858,7 +1857,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1858 | /* Record GP times before starting GP, hence smp_store_release(). */ | 1857 | /* Record GP times before starting GP, hence smp_store_release(). */ |
1859 | smp_store_release(&rsp->gpnum, rsp->gpnum + 1); | 1858 | smp_store_release(&rsp->gpnum, rsp->gpnum + 1); |
1860 | trace_rcu_grace_period(rsp->name, rsp->gpnum, TPS("start")); | 1859 | trace_rcu_grace_period(rsp->name, rsp->gpnum, TPS("start")); |
1861 | raw_spin_unlock_irq(&rnp->lock); | 1860 | raw_spin_unlock_irq_rcu_node(rnp); |
1862 | 1861 | ||
1863 | /* | 1862 | /* |
1864 | * Apply per-leaf buffered online and offline operations to the | 1863 | * Apply per-leaf buffered online and offline operations to the |
@@ -1872,7 +1871,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1872 | if (rnp->qsmaskinit == rnp->qsmaskinitnext && | 1871 | if (rnp->qsmaskinit == rnp->qsmaskinitnext && |
1873 | !rnp->wait_blkd_tasks) { | 1872 | !rnp->wait_blkd_tasks) { |
1874 | /* Nothing to do on this leaf rcu_node structure. */ | 1873 | /* Nothing to do on this leaf rcu_node structure. */ |
1875 | raw_spin_unlock_irq(&rnp->lock); | 1874 | raw_spin_unlock_irq_rcu_node(rnp); |
1876 | continue; | 1875 | continue; |
1877 | } | 1876 | } |
1878 | 1877 | ||
@@ -1906,7 +1905,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1906 | rcu_cleanup_dead_rnp(rnp); | 1905 | rcu_cleanup_dead_rnp(rnp); |
1907 | } | 1906 | } |
1908 | 1907 | ||
1909 | raw_spin_unlock_irq(&rnp->lock); | 1908 | raw_spin_unlock_irq_rcu_node(rnp); |
1910 | } | 1909 | } |
1911 | 1910 | ||
1912 | /* | 1911 | /* |
@@ -1937,7 +1936,7 @@ static bool rcu_gp_init(struct rcu_state *rsp) | |||
1937 | trace_rcu_grace_period_init(rsp->name, rnp->gpnum, | 1936 | trace_rcu_grace_period_init(rsp->name, rnp->gpnum, |
1938 | rnp->level, rnp->grplo, | 1937 | rnp->level, rnp->grplo, |
1939 | rnp->grphi, rnp->qsmask); | 1938 | rnp->grphi, rnp->qsmask); |
1940 | raw_spin_unlock_irq(&rnp->lock); | 1939 | raw_spin_unlock_irq_rcu_node(rnp); |
1941 | cond_resched_rcu_qs(); | 1940 | cond_resched_rcu_qs(); |
1942 | WRITE_ONCE(rsp->gp_activity, jiffies); | 1941 | WRITE_ONCE(rsp->gp_activity, jiffies); |
1943 | } | 1942 | } |
@@ -1995,7 +1994,7 @@ static void rcu_gp_fqs(struct rcu_state *rsp, bool first_time) | |||
1995 | raw_spin_lock_irq_rcu_node(rnp); | 1994 | raw_spin_lock_irq_rcu_node(rnp); |
1996 | WRITE_ONCE(rsp->gp_flags, | 1995 | WRITE_ONCE(rsp->gp_flags, |
1997 | READ_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS); | 1996 | READ_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS); |
1998 | raw_spin_unlock_irq(&rnp->lock); | 1997 | raw_spin_unlock_irq_rcu_node(rnp); |
1999 | } | 1998 | } |
2000 | } | 1999 | } |
2001 | 2000 | ||
@@ -2025,7 +2024,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) | |||
2025 | * safe for us to drop the lock in order to mark the grace | 2024 | * safe for us to drop the lock in order to mark the grace |
2026 | * period as completed in all of the rcu_node structures. | 2025 | * period as completed in all of the rcu_node structures. |
2027 | */ | 2026 | */ |
2028 | raw_spin_unlock_irq(&rnp->lock); | 2027 | raw_spin_unlock_irq_rcu_node(rnp); |
2029 | 2028 | ||
2030 | /* | 2029 | /* |
2031 | * Propagate new ->completed value to rcu_node structures so | 2030 | * Propagate new ->completed value to rcu_node structures so |
@@ -2047,7 +2046,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) | |||
2047 | /* smp_mb() provided by prior unlock-lock pair. */ | 2046 | /* smp_mb() provided by prior unlock-lock pair. */ |
2048 | nocb += rcu_future_gp_cleanup(rsp, rnp); | 2047 | nocb += rcu_future_gp_cleanup(rsp, rnp); |
2049 | sq = rcu_nocb_gp_get(rnp); | 2048 | sq = rcu_nocb_gp_get(rnp); |
2050 | raw_spin_unlock_irq(&rnp->lock); | 2049 | raw_spin_unlock_irq_rcu_node(rnp); |
2051 | rcu_nocb_gp_cleanup(sq); | 2050 | rcu_nocb_gp_cleanup(sq); |
2052 | cond_resched_rcu_qs(); | 2051 | cond_resched_rcu_qs(); |
2053 | WRITE_ONCE(rsp->gp_activity, jiffies); | 2052 | WRITE_ONCE(rsp->gp_activity, jiffies); |
@@ -2070,7 +2069,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) | |||
2070 | READ_ONCE(rsp->gpnum), | 2069 | READ_ONCE(rsp->gpnum), |
2071 | TPS("newreq")); | 2070 | TPS("newreq")); |
2072 | } | 2071 | } |
2073 | raw_spin_unlock_irq(&rnp->lock); | 2072 | raw_spin_unlock_irq_rcu_node(rnp); |
2074 | } | 2073 | } |
2075 | 2074 | ||
2076 | /* | 2075 | /* |
@@ -2236,18 +2235,20 @@ static bool rcu_start_gp(struct rcu_state *rsp) | |||
2236 | } | 2235 | } |
2237 | 2236 | ||
2238 | /* | 2237 | /* |
2239 | * Report a full set of quiescent states to the specified rcu_state | 2238 | * Report a full set of quiescent states to the specified rcu_state data |
2240 | * data structure. This involves cleaning up after the prior grace | 2239 | * structure. Invoke rcu_gp_kthread_wake() to awaken the grace-period |
2241 | * period and letting rcu_start_gp() start up the next grace period | 2240 | * kthread if another grace period is required. Whether we wake |
2242 | * if one is needed. Note that the caller must hold rnp->lock, which | 2241 | * the grace-period kthread or it awakens itself for the next round |
2243 | * is released before return. | 2242 | * of quiescent-state forcing, that kthread will clean up after the |
2243 | * just-completed grace period. Note that the caller must hold rnp->lock, | ||
2244 | * which is released before return. | ||
2244 | */ | 2245 | */ |
2245 | static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) | 2246 | static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) |
2246 | __releases(rcu_get_root(rsp)->lock) | 2247 | __releases(rcu_get_root(rsp)->lock) |
2247 | { | 2248 | { |
2248 | WARN_ON_ONCE(!rcu_gp_in_progress(rsp)); | 2249 | WARN_ON_ONCE(!rcu_gp_in_progress(rsp)); |
2249 | WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS); | 2250 | WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS); |
2250 | raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags); | 2251 | raw_spin_unlock_irqrestore_rcu_node(rcu_get_root(rsp), flags); |
2251 | swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */ | 2252 | swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */ |
2252 | } | 2253 | } |
2253 | 2254 | ||
@@ -2277,7 +2278,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, | |||
2277 | * Our bit has already been cleared, or the | 2278 | * Our bit has already been cleared, or the |
2278 | * relevant grace period is already over, so done. | 2279 | * relevant grace period is already over, so done. |
2279 | */ | 2280 | */ |
2280 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2281 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2281 | return; | 2282 | return; |
2282 | } | 2283 | } |
2283 | WARN_ON_ONCE(oldmask); /* Any child must be all zeroed! */ | 2284 | WARN_ON_ONCE(oldmask); /* Any child must be all zeroed! */ |
@@ -2289,7 +2290,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, | |||
2289 | if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { | 2290 | if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { |
2290 | 2291 | ||
2291 | /* Other bits still set at this level, so done. */ | 2292 | /* Other bits still set at this level, so done. */ |
2292 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2293 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2293 | return; | 2294 | return; |
2294 | } | 2295 | } |
2295 | mask = rnp->grpmask; | 2296 | mask = rnp->grpmask; |
@@ -2299,7 +2300,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, | |||
2299 | 2300 | ||
2300 | break; | 2301 | break; |
2301 | } | 2302 | } |
2302 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2303 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2303 | rnp_c = rnp; | 2304 | rnp_c = rnp; |
2304 | rnp = rnp->parent; | 2305 | rnp = rnp->parent; |
2305 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 2306 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
@@ -2331,7 +2332,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_state *rsp, | |||
2331 | 2332 | ||
2332 | if (rcu_state_p == &rcu_sched_state || rsp != rcu_state_p || | 2333 | if (rcu_state_p == &rcu_sched_state || rsp != rcu_state_p || |
2333 | rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { | 2334 | rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { |
2334 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2335 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2335 | return; /* Still need more quiescent states! */ | 2336 | return; /* Still need more quiescent states! */ |
2336 | } | 2337 | } |
2337 | 2338 | ||
@@ -2348,19 +2349,14 @@ static void rcu_report_unblock_qs_rnp(struct rcu_state *rsp, | |||
2348 | /* Report up the rest of the hierarchy, tracking current ->gpnum. */ | 2349 | /* Report up the rest of the hierarchy, tracking current ->gpnum. */ |
2349 | gps = rnp->gpnum; | 2350 | gps = rnp->gpnum; |
2350 | mask = rnp->grpmask; | 2351 | mask = rnp->grpmask; |
2351 | raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ | 2352 | raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled. */ |
2352 | raw_spin_lock_rcu_node(rnp_p); /* irqs already disabled. */ | 2353 | raw_spin_lock_rcu_node(rnp_p); /* irqs already disabled. */ |
2353 | rcu_report_qs_rnp(mask, rsp, rnp_p, gps, flags); | 2354 | rcu_report_qs_rnp(mask, rsp, rnp_p, gps, flags); |
2354 | } | 2355 | } |
2355 | 2356 | ||
2356 | /* | 2357 | /* |
2357 | * Record a quiescent state for the specified CPU to that CPU's rcu_data | 2358 | * Record a quiescent state for the specified CPU to that CPU's rcu_data |
2358 | * structure. This must be either called from the specified CPU, or | 2359 | * structure. This must be called from the specified CPU. |
2359 | * called when the specified CPU is known to be offline (and when it is | ||
2360 | * also known that no other CPU is concurrently trying to help the offline | ||
2361 | * CPU). The lastcomp argument is used to make sure we are still in the | ||
2362 | * grace period of interest. We don't want to end the current grace period | ||
2363 | * based on quiescent states detected in an earlier grace period! | ||
2364 | */ | 2360 | */ |
2365 | static void | 2361 | static void |
2366 | rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) | 2362 | rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) |
@@ -2385,14 +2381,14 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) | |||
2385 | */ | 2381 | */ |
2386 | rdp->cpu_no_qs.b.norm = true; /* need qs for new gp. */ | 2382 | rdp->cpu_no_qs.b.norm = true; /* need qs for new gp. */ |
2387 | rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr); | 2383 | rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr); |
2388 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2384 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2389 | return; | 2385 | return; |
2390 | } | 2386 | } |
2391 | mask = rdp->grpmask; | 2387 | mask = rdp->grpmask; |
2392 | if ((rnp->qsmask & mask) == 0) { | 2388 | if ((rnp->qsmask & mask) == 0) { |
2393 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2389 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2394 | } else { | 2390 | } else { |
2395 | rdp->core_needs_qs = 0; | 2391 | rdp->core_needs_qs = false; |
2396 | 2392 | ||
2397 | /* | 2393 | /* |
2398 | * This GP can't end until cpu checks in, so all of our | 2394 | * This GP can't end until cpu checks in, so all of our |
@@ -2601,10 +2597,11 @@ static void rcu_cleanup_dead_rnp(struct rcu_node *rnp_leaf) | |||
2601 | rnp->qsmaskinit &= ~mask; | 2597 | rnp->qsmaskinit &= ~mask; |
2602 | rnp->qsmask &= ~mask; | 2598 | rnp->qsmask &= ~mask; |
2603 | if (rnp->qsmaskinit) { | 2599 | if (rnp->qsmaskinit) { |
2604 | raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ | 2600 | raw_spin_unlock_rcu_node(rnp); |
2601 | /* irqs remain disabled. */ | ||
2605 | return; | 2602 | return; |
2606 | } | 2603 | } |
2607 | raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ | 2604 | raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled. */ |
2608 | } | 2605 | } |
2609 | } | 2606 | } |
2610 | 2607 | ||
@@ -2627,7 +2624,7 @@ static void rcu_cleanup_dying_idle_cpu(int cpu, struct rcu_state *rsp) | |||
2627 | mask = rdp->grpmask; | 2624 | mask = rdp->grpmask; |
2628 | raw_spin_lock_irqsave_rcu_node(rnp, flags); /* Enforce GP memory-order guarantee. */ | 2625 | raw_spin_lock_irqsave_rcu_node(rnp, flags); /* Enforce GP memory-order guarantee. */ |
2629 | rnp->qsmaskinitnext &= ~mask; | 2626 | rnp->qsmaskinitnext &= ~mask; |
2630 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2627 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2631 | } | 2628 | } |
2632 | 2629 | ||
2633 | /* | 2630 | /* |
@@ -2861,7 +2858,7 @@ static void force_qs_rnp(struct rcu_state *rsp, | |||
2861 | rcu_report_qs_rnp(mask, rsp, rnp, rnp->gpnum, flags); | 2858 | rcu_report_qs_rnp(mask, rsp, rnp, rnp->gpnum, flags); |
2862 | } else { | 2859 | } else { |
2863 | /* Nothing to do here, so just drop the lock. */ | 2860 | /* Nothing to do here, so just drop the lock. */ |
2864 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 2861 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
2865 | } | 2862 | } |
2866 | } | 2863 | } |
2867 | } | 2864 | } |
@@ -2897,11 +2894,11 @@ static void force_quiescent_state(struct rcu_state *rsp) | |||
2897 | raw_spin_unlock(&rnp_old->fqslock); | 2894 | raw_spin_unlock(&rnp_old->fqslock); |
2898 | if (READ_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { | 2895 | if (READ_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { |
2899 | rsp->n_force_qs_lh++; | 2896 | rsp->n_force_qs_lh++; |
2900 | raw_spin_unlock_irqrestore(&rnp_old->lock, flags); | 2897 | raw_spin_unlock_irqrestore_rcu_node(rnp_old, flags); |
2901 | return; /* Someone beat us to it. */ | 2898 | return; /* Someone beat us to it. */ |
2902 | } | 2899 | } |
2903 | WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS); | 2900 | WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS); |
2904 | raw_spin_unlock_irqrestore(&rnp_old->lock, flags); | 2901 | raw_spin_unlock_irqrestore_rcu_node(rnp_old, flags); |
2905 | swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */ | 2902 | swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */ |
2906 | } | 2903 | } |
2907 | 2904 | ||
@@ -2927,7 +2924,7 @@ __rcu_process_callbacks(struct rcu_state *rsp) | |||
2927 | if (cpu_needs_another_gp(rsp, rdp)) { | 2924 | if (cpu_needs_another_gp(rsp, rdp)) { |
2928 | raw_spin_lock_rcu_node(rcu_get_root(rsp)); /* irqs disabled. */ | 2925 | raw_spin_lock_rcu_node(rcu_get_root(rsp)); /* irqs disabled. */ |
2929 | needwake = rcu_start_gp(rsp); | 2926 | needwake = rcu_start_gp(rsp); |
2930 | raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags); | 2927 | raw_spin_unlock_irqrestore_rcu_node(rcu_get_root(rsp), flags); |
2931 | if (needwake) | 2928 | if (needwake) |
2932 | rcu_gp_kthread_wake(rsp); | 2929 | rcu_gp_kthread_wake(rsp); |
2933 | } else { | 2930 | } else { |
@@ -3018,7 +3015,7 @@ static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp, | |||
3018 | 3015 | ||
3019 | raw_spin_lock_rcu_node(rnp_root); | 3016 | raw_spin_lock_rcu_node(rnp_root); |
3020 | needwake = rcu_start_gp(rsp); | 3017 | needwake = rcu_start_gp(rsp); |
3021 | raw_spin_unlock(&rnp_root->lock); | 3018 | raw_spin_unlock_rcu_node(rnp_root); |
3022 | if (needwake) | 3019 | if (needwake) |
3023 | rcu_gp_kthread_wake(rsp); | 3020 | rcu_gp_kthread_wake(rsp); |
3024 | } else { | 3021 | } else { |
@@ -3438,14 +3435,14 @@ static void sync_exp_reset_tree_hotplug(struct rcu_state *rsp) | |||
3438 | rcu_for_each_leaf_node(rsp, rnp) { | 3435 | rcu_for_each_leaf_node(rsp, rnp) { |
3439 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 3436 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
3440 | if (rnp->expmaskinit == rnp->expmaskinitnext) { | 3437 | if (rnp->expmaskinit == rnp->expmaskinitnext) { |
3441 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3438 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3442 | continue; /* No new CPUs, nothing to do. */ | 3439 | continue; /* No new CPUs, nothing to do. */ |
3443 | } | 3440 | } |
3444 | 3441 | ||
3445 | /* Update this node's mask, track old value for propagation. */ | 3442 | /* Update this node's mask, track old value for propagation. */ |
3446 | oldmask = rnp->expmaskinit; | 3443 | oldmask = rnp->expmaskinit; |
3447 | rnp->expmaskinit = rnp->expmaskinitnext; | 3444 | rnp->expmaskinit = rnp->expmaskinitnext; |
3448 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3445 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3449 | 3446 | ||
3450 | /* If was already nonzero, nothing to propagate. */ | 3447 | /* If was already nonzero, nothing to propagate. */ |
3451 | if (oldmask) | 3448 | if (oldmask) |
@@ -3460,7 +3457,7 @@ static void sync_exp_reset_tree_hotplug(struct rcu_state *rsp) | |||
3460 | if (rnp_up->expmaskinit) | 3457 | if (rnp_up->expmaskinit) |
3461 | done = true; | 3458 | done = true; |
3462 | rnp_up->expmaskinit |= mask; | 3459 | rnp_up->expmaskinit |= mask; |
3463 | raw_spin_unlock_irqrestore(&rnp_up->lock, flags); | 3460 | raw_spin_unlock_irqrestore_rcu_node(rnp_up, flags); |
3464 | if (done) | 3461 | if (done) |
3465 | break; | 3462 | break; |
3466 | mask = rnp_up->grpmask; | 3463 | mask = rnp_up->grpmask; |
@@ -3483,7 +3480,7 @@ static void __maybe_unused sync_exp_reset_tree(struct rcu_state *rsp) | |||
3483 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 3480 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
3484 | WARN_ON_ONCE(rnp->expmask); | 3481 | WARN_ON_ONCE(rnp->expmask); |
3485 | rnp->expmask = rnp->expmaskinit; | 3482 | rnp->expmask = rnp->expmaskinit; |
3486 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3483 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3487 | } | 3484 | } |
3488 | } | 3485 | } |
3489 | 3486 | ||
@@ -3524,11 +3521,11 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, | |||
3524 | if (!rnp->expmask) | 3521 | if (!rnp->expmask) |
3525 | rcu_initiate_boost(rnp, flags); | 3522 | rcu_initiate_boost(rnp, flags); |
3526 | else | 3523 | else |
3527 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3524 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3528 | break; | 3525 | break; |
3529 | } | 3526 | } |
3530 | if (rnp->parent == NULL) { | 3527 | if (rnp->parent == NULL) { |
3531 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3528 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3532 | if (wake) { | 3529 | if (wake) { |
3533 | smp_mb(); /* EGP done before wake_up(). */ | 3530 | smp_mb(); /* EGP done before wake_up(). */ |
3534 | swake_up(&rsp->expedited_wq); | 3531 | swake_up(&rsp->expedited_wq); |
@@ -3536,7 +3533,7 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, | |||
3536 | break; | 3533 | break; |
3537 | } | 3534 | } |
3538 | mask = rnp->grpmask; | 3535 | mask = rnp->grpmask; |
3539 | raw_spin_unlock(&rnp->lock); /* irqs remain disabled */ | 3536 | raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled */ |
3540 | rnp = rnp->parent; | 3537 | rnp = rnp->parent; |
3541 | raw_spin_lock_rcu_node(rnp); /* irqs already disabled */ | 3538 | raw_spin_lock_rcu_node(rnp); /* irqs already disabled */ |
3542 | WARN_ON_ONCE(!(rnp->expmask & mask)); | 3539 | WARN_ON_ONCE(!(rnp->expmask & mask)); |
@@ -3571,7 +3568,7 @@ static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp, | |||
3571 | 3568 | ||
3572 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 3569 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
3573 | if (!(rnp->expmask & mask)) { | 3570 | if (!(rnp->expmask & mask)) { |
3574 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3571 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3575 | return; | 3572 | return; |
3576 | } | 3573 | } |
3577 | rnp->expmask &= ~mask; | 3574 | rnp->expmask &= ~mask; |
@@ -3732,7 +3729,7 @@ static void sync_rcu_exp_select_cpus(struct rcu_state *rsp, | |||
3732 | */ | 3729 | */ |
3733 | if (rcu_preempt_has_tasks(rnp)) | 3730 | if (rcu_preempt_has_tasks(rnp)) |
3734 | rnp->exp_tasks = rnp->blkd_tasks.next; | 3731 | rnp->exp_tasks = rnp->blkd_tasks.next; |
3735 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3732 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3736 | 3733 | ||
3737 | /* IPI the remaining CPUs for expedited quiescent state. */ | 3734 | /* IPI the remaining CPUs for expedited quiescent state. */ |
3738 | mask = 1; | 3735 | mask = 1; |
@@ -3749,7 +3746,7 @@ retry_ipi: | |||
3749 | raw_spin_lock_irqsave_rcu_node(rnp, flags); | 3746 | raw_spin_lock_irqsave_rcu_node(rnp, flags); |
3750 | if (cpu_online(cpu) && | 3747 | if (cpu_online(cpu) && |
3751 | (rnp->expmask & mask)) { | 3748 | (rnp->expmask & mask)) { |
3752 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3749 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3753 | schedule_timeout_uninterruptible(1); | 3750 | schedule_timeout_uninterruptible(1); |
3754 | if (cpu_online(cpu) && | 3751 | if (cpu_online(cpu) && |
3755 | (rnp->expmask & mask)) | 3752 | (rnp->expmask & mask)) |
@@ -3758,7 +3755,7 @@ retry_ipi: | |||
3758 | } | 3755 | } |
3759 | if (!(rnp->expmask & mask)) | 3756 | if (!(rnp->expmask & mask)) |
3760 | mask_ofl_ipi &= ~mask; | 3757 | mask_ofl_ipi &= ~mask; |
3761 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 3758 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
3762 | } | 3759 | } |
3763 | /* Report quiescent states for those that went offline. */ | 3760 | /* Report quiescent states for those that went offline. */ |
3764 | mask_ofl_test |= mask_ofl_ipi; | 3761 | mask_ofl_test |= mask_ofl_ipi; |
@@ -4165,7 +4162,7 @@ static void rcu_init_new_rnp(struct rcu_node *rnp_leaf) | |||
4165 | return; | 4162 | return; |
4166 | raw_spin_lock_rcu_node(rnp); /* Interrupts already disabled. */ | 4163 | raw_spin_lock_rcu_node(rnp); /* Interrupts already disabled. */ |
4167 | rnp->qsmaskinit |= mask; | 4164 | rnp->qsmaskinit |= mask; |
4168 | raw_spin_unlock(&rnp->lock); /* Interrupts remain disabled. */ | 4165 | raw_spin_unlock_rcu_node(rnp); /* Interrupts remain disabled. */ |
4169 | } | 4166 | } |
4170 | } | 4167 | } |
4171 | 4168 | ||
@@ -4189,7 +4186,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) | |||
4189 | rdp->rsp = rsp; | 4186 | rdp->rsp = rsp; |
4190 | mutex_init(&rdp->exp_funnel_mutex); | 4187 | mutex_init(&rdp->exp_funnel_mutex); |
4191 | rcu_boot_init_nocb_percpu_data(rdp); | 4188 | rcu_boot_init_nocb_percpu_data(rdp); |
4192 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 4189 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
4193 | } | 4190 | } |
4194 | 4191 | ||
4195 | /* | 4192 | /* |
@@ -4217,7 +4214,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp) | |||
4217 | rcu_sysidle_init_percpu_data(rdp->dynticks); | 4214 | rcu_sysidle_init_percpu_data(rdp->dynticks); |
4218 | atomic_set(&rdp->dynticks->dynticks, | 4215 | atomic_set(&rdp->dynticks->dynticks, |
4219 | (atomic_read(&rdp->dynticks->dynticks) & ~0x1) + 1); | 4216 | (atomic_read(&rdp->dynticks->dynticks) & ~0x1) + 1); |
4220 | raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ | 4217 | raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled. */ |
4221 | 4218 | ||
4222 | /* | 4219 | /* |
4223 | * Add CPU to leaf rcu_node pending-online bitmask. Any needed | 4220 | * Add CPU to leaf rcu_node pending-online bitmask. Any needed |
@@ -4238,7 +4235,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp) | |||
4238 | rdp->rcu_qs_ctr_snap = per_cpu(rcu_qs_ctr, cpu); | 4235 | rdp->rcu_qs_ctr_snap = per_cpu(rcu_qs_ctr, cpu); |
4239 | rdp->core_needs_qs = false; | 4236 | rdp->core_needs_qs = false; |
4240 | trace_rcu_grace_period(rsp->name, rdp->gpnum, TPS("cpuonl")); | 4237 | trace_rcu_grace_period(rsp->name, rdp->gpnum, TPS("cpuonl")); |
4241 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 4238 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
4242 | } | 4239 | } |
4243 | 4240 | ||
4244 | static void rcu_prepare_cpu(int cpu) | 4241 | static void rcu_prepare_cpu(int cpu) |
@@ -4360,7 +4357,7 @@ static int __init rcu_spawn_gp_kthread(void) | |||
4360 | sp.sched_priority = kthread_prio; | 4357 | sp.sched_priority = kthread_prio; |
4361 | sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); | 4358 | sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); |
4362 | } | 4359 | } |
4363 | raw_spin_unlock_irqrestore(&rnp->lock, flags); | 4360 | raw_spin_unlock_irqrestore_rcu_node(rnp, flags); |
4364 | wake_up_process(t); | 4361 | wake_up_process(t); |
4365 | } | 4362 | } |
4366 | rcu_spawn_nocb_kthreads(); | 4363 | rcu_spawn_nocb_kthreads(); |
@@ -4451,8 +4448,8 @@ static void __init rcu_init_one(struct rcu_state *rsp) | |||
4451 | cpustride *= levelspread[i]; | 4448 | cpustride *= levelspread[i]; |
4452 | rnp = rsp->level[i]; | 4449 | rnp = rsp->level[i]; |
4453 | for (j = 0; j < levelcnt[i]; j++, rnp++) { | 4450 | for (j = 0; j < levelcnt[i]; j++, rnp++) { |
4454 | raw_spin_lock_init(&rnp->lock); | 4451 | raw_spin_lock_init(&ACCESS_PRIVATE(rnp, lock)); |
4455 | lockdep_set_class_and_name(&rnp->lock, | 4452 | lockdep_set_class_and_name(&ACCESS_PRIVATE(rnp, lock), |
4456 | &rcu_node_class[i], buf[i]); | 4453 | &rcu_node_class[i], buf[i]); |
4457 | raw_spin_lock_init(&rnp->fqslock); | 4454 | raw_spin_lock_init(&rnp->fqslock); |
4458 | lockdep_set_class_and_name(&rnp->fqslock, | 4455 | lockdep_set_class_and_name(&rnp->fqslock, |